P03 TN NO: N-1627 Robert &. Walden Words Hole Oceanographic Inst. Wosds Hole, MA 02543 TITLE: INTERACTION OF ANCHORS WITH SOIL AND ANCHOR DESIGN S AUTHOR: _ Robert J. Taylor DATE: . April 1982 SPONSOR: Naval Facilities Engineering Command PROGRAM NO: ss YF59.556.091.01.205 INOUE NAVAL CIVIL ENGINEERING LABORATORY PORT HUENEME, CALIFORNIA 93043 TH Approved for public release; distribution unlimited. Ae WOINOELL T OSbEhoOg TOEO g A ON 1OHM/Tan dS = 8 = E = — -B_—88Z#04'E 19 “ON Bored as “G2'Z$ ao1s4 “sosnsBoW Pus siUBIEM JO S11UN ’9BZ “IaNd “OSN S _ SON 865 ‘8a|qe} pajjeyep e140 pus SUOISIGAUOD 19Bx9 18430 104 *(Aj1DBx8) PGT = Ul lL, Nn = = ea = = (Z€ w = = ainjesaduay Bunoesaqns aunjeiaduia} ns =] = Io SnisjaQ 48H2) 6/G yeyuaiyey do Be = Q98x9) 3UNLVHAdWAL aunyesaduiay (ze ppe aunyesaduiay a Ss = n pu suayauy 91qNn9 920 spaeA aiqno gPA do qayuasyey uay}) S/6 snisja9 35 : = = et Sajal 91QNd £00 398} 91qQNd y 2. 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F say tw pA spieA VL s4ajauw w = = i a ue - ; ye ; ah y yoay ee S19}elW w os -= = ul sayou! v0 $49} alu 1}Ua0 wo & = SS = wo s4a}atu}yuaa oe yaa} y ul sayou! 0'0 $19} atu!) |IUW ww ee == — wo $49}aUU1}Ua9 qz. sayou! ul HIONS1 s =e = HIONa1 aS loquiAs puly Of Aq Aidninw MOU NO, UB, joquiAg i= = = joquiAs pury OL Aq Aidninw mouy no, ay =—- }OqUIAS Saanseay) 9s,ay WOsy SUOISQAUOZD OJEWIXOAKddYy Re = = sainseay 210; 0} SuOIssaAUOD eyeLUIXoaddy Niger 8 = == .) SUOLOVA NOISUAANOD OLN LAW me ‘2400 ae EF =i Was Ss ie | ih me gy day i we a] He Ko Phy ie te He ie H | RE OR | ry ae 7 ci a ‘ee reread 2 soe Val Ba ve a; iH) si vate he ta ae a ri ‘ i 1H j Perey " f j Ai Unclassified SECURITY CLASSIFICATION OF THIS PAGE (When Data Entered) 1. REPORT NUMBER 2. GOVT ACCESSION NO. 3. RECIPIENT'S CATALOG NUMBER 4. TITLE (and Subtitle) 5S. TYPE OF REPORT & PERIOD COVERED INTERACTION OF ANCHORS WITH SOIL Final; Jan 77 — Jan 81 Aaa 6. CONTRACT OR GRANT NUMBER(s) 7. AUTHOR(s) Robert J. Taylor 10. PROGRAM ELEMENT. PROJECT, TASK AREA & WORK UNIT NUMBERS 62759N; YF59.556.091.01.205 12. REPORT DATE April 1982 13. NUMBER OF PAGES 44 15. SECURITY CLASS. (of this report) 9. PERFORMING ORGANIZATION NAME AND AODRESS NAVAL CIVIL ENGINEERING LABORATORY Port Hueneme, California 93043 CONTROLLING OFFICE NAME AND ADDRESS Naval Facilities Engineering Command Washington, DC 22332 - MONITORING AGENCY NAME & ADORESS(il dilferent from Controlling Office) Unclassified DECL ASSIFIC ATION ‘DOWNGRADING SCHEDULE Sa. . DISTRIBUTION STATEMENT (of this Report) Approved for public release; distribution unlimited. . DISTRIBUTION STATEMENT (of the abstract entered in Block 20, if different from Report) SUPPLEMENTARY NOTES . KEY WORDS (Continue on reverse side if necessary and identily by block number) Anchors, site selection, ocean soils, deadweight anchors, direct-embedment anchors, drag-embedment anchors, pile anchors. . ABSTRACT (Continue on reverse side If necessary and identify by block number) The report provides a practical up-to-date guide that enables the practicing engineer to select and size common anchor types, including direct-embedment anchors, deadweight anchors, drag-embedment anchors, and pile anchors. For each anchor type, the report includes site survey recommendations, a brief description of various anchors within each anchor category, methods for determining anchor performance, and, in certain cases, continued DD FORM EDITION OF ! NOV 65 1S OBSOLETE 4 Anza) 1473 Unclassified SECURITY CLASSIFICATION OF THIS PAGE (When Data Entered) ~ &MOIT SS HetiNt: oe Wien Jantar dered den elena. ital amrerceithided QAALYEO O6)69° @ * ROTA 80 Be Te rae 18 dal = TY nal jlealt jl Fae n a aac amet ® ¥ J ‘ : \ RT eat ae rae Ne «As mm en co au Trew aw a §2 ; yaeevee . R0L.20. 1%. 62 4 ey { 1 Ee aie $+ Anema Harman ae ath ¥} rir ae ‘ geet aren - ite baltieegtnets = os ait ie Bay “TMan HIN Cada MTS) (er APS poeteweanea STATIN 7 eww = =a j . PPR eS ho er PaCros yaa as | permet tees serieiliilldctl Seu renee cs) i irae sal ik pun Sy¥ berimileas atadtiselb oxsesiirn oblelaty gal ‘ wea CE dee ee ee eT —. a0 v by > Fete yp ome ia DAaAah inal Verve Wy Oe & A Seep: a Wi r serve een Pap th et reels li pms nye acer emir peaganeseb aneibcinee s=deeenbre ui mod Tis tiaras tae Usodens tA rwebeenty ee Phy oy 408) Uaywatng OTe ew at ai aArontonep roomie te ~_ ee wo ENE EE NED 4 enters) 44 “Wrulene Giles ants * arrest ri anatase 8 oe an ETT DD qaiocorzy ods eoldecis ted? abley snab-opy elias al miabrwig age: oT hy mintioas jmerhaineMavib yaitbulbe oq sodas seein Ghie ban goles oF Same UE P1OT wworteia Sie Ly Kodoce iiseabddeny gaat Petey telgiranls cede. NY) m menses 2iraiir to nokbetitees dund 2 .acbebitwamuiees Weve Ae ets vt TROT ; | (estes AiRT TTD Teh bile i801 adie tears ‘gnininnerh tt ete MID He te done od t is : i im sy ery? vocdode : : {eedemer Sebid x6 ese) Wath SaRSERHA NY Shin ah enet on Don race { Oricon: Spent thats re S/T ssh ie ey lr Pte rote ire peechere te mercenaria ‘ 1 Le ‘ astral ¥Tte ES, dae Oe wo eA tia’ VG MOMTR OV ibea Do wha ao Unclassified SECURITY CLASSIFICATION OF THIS PAGE(When Data Entered) 20. Continued suggestions for improving poor anchor behavior. Sources for additional information are suggested where the treatment of a broad topic is necessarily limited. Naval Civil Engineering Laboratory INTERACTION OF ANCHORS WITH SOIL AND ANCHOR DESIGN (Final), by Robert J. Taylor TN-1627 44ppillus April1982 Unclassified 1. Anchors 2. Site selection I. YF59.556.091.01.205 The report provides a practical up-to-date guide that enables the practicing engineer to select and size common anchor types, including direct-embedment anchors, deadweight anchors, drag-embedment anchors, and pile anchors. For each anchor type, the report includes site survey recommendations, 2 brief description of various anchors within each anchor category, methods for determining anchor performance, and, in certain cases, suggestions for improving poor anchor behavior. Sources for additiqnal information are suggested where the treatment of a broad topic is necessarily limited. Unclassified SECURITY CLASSIFICATION OF THIS PAGE(When Data Entered) ae a a pe AoCsinautel lengthy Tor ewe” MW ate) pet Geo Aorienil yeu ssog d F ' Lan oe ae tee nae “cles leaned sew here vies sereeliradnaid ost iilieel Ps: hoe inane sm ere ttt le i vimeveding vostoegiget W:> eal ROMA OHA Oe HTN SCT We MONEDA TY ' 4 wlyaT | | pri vat edi) Hore ter tiwelact) Rear ya aul gy SLGE-MYT POLLO. GAR. eeT yy Ce iirakm sabes eo dra: £° Toei gueskrzarey 1s eorlelvces Sante ats cay WRab re eRgIE Maayd carrey a thitwry yeote FS tisiovelawh zordene yards rath eA OA Wire hones ae has & Tat elt TY? Totstn doy VOR arose eR Jeodisra tinct ochre jute Ghdtiw eudlvie wuntrav to axntvetveagh Tabdl MM Meelis co fey sae athe onees here de Dee soqamrobeeg gree nom abe sol dbothem jnepete di no tentetal tukpithtie wl mero bye sso ness ukwerecenl wi) acne dapatersld yflvomaycoadh ad sgt CY Hemera tis wesgin & a, Pt FOREWORD This report was prepared for presentation at "Recent Developments in Ocean Engineering," sponsored by the University of California at Berkeley in January 1981. It was written in outline format to provide a practical up-to-date guide for the practicing engineer to enable selec- tion and sizing of common anchor types including direct embedment anchors, deadweight anchors, drag embedment anchors, and pile anchors. For each anchor type, the report includes site survey recommendations, briefly describes various anchors within each anchor category, presents methods for determining anchor performance and, in certain cases, suggests practical options for improving poor anchor behavior. The topic of anchor design is broad, and this report does not pretend to provide complete solutions for all anchor selection and design problems. However, it does provide state-of-practice solutions to most general anchoring problems and makes the designer more aware of his options and the limitations of each anchor type. For complex or critical anchoring applications, the reader is referred to sources of information and references that are provided throughout the report. A majority of the information presented in this report was taken from published and unpublished reports by the Foundation Engineering Division of the Naval Civil Engineering Laboratory under the sponsorship of the Naval Facilities Engineering Command and the Department of Energy. égnsmgoleved spaco8” ga, avkdadnedoig wok boxe (Je atirioilisd t+ vitavavind ait yd baron 6 #hiveiq oF June? swifsas nt esas isw naw Ft" 3 a “salve sidevs od ivenlgos gatrissasg oy -s0% og) ,etedsa6 Jaowbodws tae7ibh gnibulonl asqys. todiqure’ aS: -axodone sliq bas ,eyonsaa thembadas ont patolisbisomoces Yovivs a¢la eshutour ga0qan eas, eiaonexq ,v10gsJe0 todsag ises alitdiw nwoduan & Sirs eJeegnue javedn Sladis? ak, baa SINS OR IAG FouING | RHE takwaitied roland: 4OO§ Brits qt Jom 200b drogie etd? hos |, beotd at teraah. & has aoisoaley yoroqe fle a0t adoksicton arartenae enotiylow azlioaxq~lo-siaz2 shivorg) aseb ai; peer to myeve o30m ‘Tomgtesh oft eodam Daa, smafiexg golcogg to xeiguo> 10% .asq¢9 aodons dows to seertationt: 4 to aepuwon of betister el isbssy add eleetsed tomar oft Juodguetds bobivoig ets, Sada’ wade) mOrIe neler maw tioqes ohdd nt betnsadsq aobseintns ails te) my a : griteraigal aoliebouel sit yd asrogay Rect Ltugrs ‘bodes. vs i qivtezonuogs 343 x9bau yrosatodud gaisegatend) Lavi) Lok “qprand YO Seamtieyad of bee Soemne? — toa Lb - wt CONTENTS SITE SURVEY ..... GENERAL FEATURES OF VARIOUS ANCHORS . PLATE ANCHORS . DRAG EMBEDMENT ANCHORS DEADWEIGHT ANCHORS PILE ANCHORS ...... ACKNOWLEDGMENTS . ...... REFERENCES ..... vi Page i : : y ie i , | ud } i : ay i : rr ii i 7 Hl i / Ui , ihe ] ; : } ni : nt al h, All ee H ‘i Hi i a ) ei y be HO) ) a es vr CY wei nga’ ob oahu Ne : . t , *; * *. * é yah o , / ; i wt aa i Ue we a * : i fh pe > Si i - * ‘ i} N i f oon Hh ve ‘ ' tt » «4 ‘ i ere ps ihe if U if : Be i er eee 4 i f Wat i : j i : oe ¥ i f cat l i \ ' 7} e H / ee a Wi Sod nt ; fi i i se SAT i i * . i SITE SURVEY A. Site Survey Requirements - Requirements differ according to: Anchor type [Pile, Deadweight, Drag, Embedment] Loading condition [Static, Dynamic] Soil type [Sand (cohesionless), Clay (cohesive) ] Mooring use [Manned, Unmanned] Minimum Recommended Site Survey Requirements Required Site Information* Anchor Type Non-Critical Mooring Critical Mooring Deadweight General seafloor type Seafloor type, depth of sedi- (mud, clay, sand, ment, areal variability, esti- rock). mate of soil cohesion, fric- tion angle, scour potential. Drag Embedment Seafloor type. Seafloor type and strength, (approximate) depth to rock, stratification in upper 10' to 30' (depending on soil type), areal variability. Plate Anchor Seafloor type; Engineering soil data to ex- depth to rock; pected embedment depth (soil o Use estimated strength, sensitivity, density, properties provid- -grain size, origin, depth to ed or other avail- rock), additional data required able info. for dynamic analysis. Pile Anchor Sediment type, Engineering soil properties to depth of sediment. full embedment depth o Use estimated (soil strength, sensitivity, properties provid- grain size, origin, density), ed or other avail- soil modulus of subgrade reac- able info. tion for laterally loaded piles. *Geologic literature survey suggested for all situations to help define soil type and existence of seafloor anomalies. | Jasmine (Berd, tdy a a | (ov tendoo) vald i aed Semmettupsl vosue ayig: *nohtaano tet oka SXlx00N Lan hyes5 *Ebew sty Aiqab , aqus sooltas2 elites ser tlidelray £2974 tam “£21 ,aoleades Sioa to: stan -Telieszeg 24054 «eSgan nots Wigourse ban 2qY7 t00ltaep 290% ed digas (stambxoxgge) "OL temp a} HOLS Pi tayts livm goa Bihgegeh) ‘Oe o4 HET ida trav [nova {aqua "HP OF 23eb. Ling Getvsenteoy £103) stiepots “eget svddinns Pot >ey (Veieagh , Evie papa, aherte O2 tiga sFrGRID: .wedg akasg bextios7 e405 finity Lathe «(Nao -eLaylany SFOS. 2H} \\ OF B8idzeq@org Ting Seki ton tend ; Asgab Troebedine Let +UIivisinges M“Wgcaxte fing) el Giienah oMigbie satis BLaxg “989% sheredua to nulubenm Liaw aelig helisaf Uileraset. yok hors r } a ; Po trent ee —~ Saliah qlad oy SMolIsuths {In 349 Setano guy OMe Sms 2e rE 2 ie heg - 0% Lamong 200l Teas te) a atte . B. Sediment Property Determination - Variety of tools exist to acquire quantitative or qualitative data. qe Static, dynamic penetrometers, in-situ Sub-bottom profiling vane shear device, corers, grab samplers side scan sonar [Refer to Lee and Clausner (1979) - Soil Sampling Techniques] - Information/Data-Sources Lamont-Doherty Geological Observatory of Columbia University, Palisades, N. Y. 10964 National Geophysical and Solar-Terrestrial Data Center, Environmental Data Service, National Oceanic and Atmospheric Administration, Boulder, Colo. 80302 Chief of Operations Division, National Ocean Survey, NOAA, 1801 Fairview Avenue, East Seattle, Wash. 98102 Chief of Operations Division, National Ocean Survey, NOAA 1439 W. York Street, Norfolk, Va. 23510 Naval Oceanographic Office, Code 3100, National Space Technology Laboratories, NSTL Station, Miss. 39522 Scripps Institution of Oceanography, La Jolla, Calif. 92093 Chief Atlantic Branch of Marine Geology, United States Geological Survey, Bldg. 13, Quissett Campus, Woods Hole, Mass. 02543 Chief Pacific Arctic Branch of Marine Geology, United States Geological Survey, 345 Middle Road, Menlo Park, Calif. 94025 Woods Hole Oceanographic Institution, Woods Hole, Mass. 02543 C. Sediment Property Estimation (When detailed physical survey not practical) - Determine whether sediments are: — Terrigenous (land-derived) sediments or pelagic (ocean-derived) sediments (e.g., pelagic clay, oozes). oye <> “gorittoxq mottod=dne cy hare aods 1ag08 4638 pbiz . seoheet doxg, (a yaebeaiiad jyoiersvnll akdoutey to wy pvet Letusanorived 292050 sted [sixseeuas : $0602 .ofod ,rebluct potiextersimbA >hawiggaee Waiviis® (08! AAO yeviud n6so0 Ae ats t dx0Y .W CAT AAOH ,ysvund oss00 (ano tie One 0. aii0t sax . | aie a wiles ~2etzosexodsl ysdlouioaT s98q wuseatuale ook “ae | epse |. 4a0e0) ~elfol af cea » he aottusise, y"ovrud Lavkgotosd asseta badint! yaolesd : baa flanexd yer RbCS0 .ausM (ololi: Seuiee td sal Sertgofoad aster? ba ttall , ygoload sttiaeh a rt pA aT 3 cSO8E tind: dae okie ee Ly fi EdekO. . aaetl »slok aboolW ao tos esane stien ss 00a090. i dot shintgish ptesgorl te (ina dyodeg Jou’ vavuite aa degles ghia wad) tate ninewbbee xadsad Acimrate = >igeleg 40 atnemibos (oavindbaBany sudasgeaxeT (waneo: val? Deasiag »+g.d) tiie asicanaaiieanamte. | 73 ENS Tropic of Cancer SUES SEIN __& SSS ESSE Ss BUNGE pass EY =~ + ~Tropic of Capricorn — - — = Terrigenous Ti1f, Distom Se peposia Ss Cay ut Ooze (Siliceous) Ocean sediment distribution Ibe Terrigenous Sediment Properties - Assume all continental shelves and slopes are terrigenous. - Typically complex and varied sediment type particularly, near-shore, glaciated areas, high current areas. - Refer to National Ocean Survey charts to determine whether sand or mud (cohesive). Sand S,-3t05 S,* 2103 If nearshore and a "grab" sample is available for grain point tae nt size determination, safe values eet rere 12m ma whickncs) alternaning with of $ and y, are: a © of sand = 33 - 40 deg Jp = S60 hg’ at Om wo B80 kg/m? at om sigan * | rata G Sandy silt 880 (55) g : Silty sand 880 (55) g 5 Uniform sand 880 (55) ye 3 Well-graded sand 960 (60) i 3 For-locations classed as on eeen Abyssal Plains properties for 1 ePa = a.4s bia? turbidites are appropriate. Proxinal ~< 30 miles from shore Distal ~> 30 miles from shore o s 10 4, o=) Typical strength profile - turbidites. emo S exe 0) a! é i ~ ern 430) 942M « ry at rou rd dy re out, anidnas 04 210 “ re ee ee er ee ee es eee 4 © r % weed oy “urpdeet > oe / 0 eS rm dey / j j J i ery * 2TH Saag nay? Jenn “ aqot a Bets xov fede Fos pde haga: tke paras tou hovoew gages watignee Vilesteyt nohadieb seni ne cane ~ asisvaront Perey eae Pert 3 2egte tneyes: iigid , aaa ake cial Wrode-r8 loeb 02, efuedo yoynwe, weno Sapo tan oy 1938 ae ye I aa Diag 't0 bear j ——7— leap aie inf 7 ce ah | Pal } vel FT d sy | : tisredd e a | ees 1 ae ha 2 1 ‘ 4 f. A . “gare” # bus srodesag fi aioe 262 gidelions abs i , f | | rep ter whens, notion tan steb, H arse | i ” } : oe ose ty pe 5 lp att 9 ate Oy ee 7 i | 1 Adio eb ee t V tyakinni aces : | | ca ree | | | ie area / { bid | (es se one as dcaies ae age sia a ive eter | ohn Sonar Naae ara “a f 4 Soesteemer = ~ A ot ee Here hy sm heme he hepa ~ ond A | rary: ; ARWOS aici at oe ‘eae? 4% sok eo Legh priel? £ f . aid otk 85: wires seat} Mere ; a Ferabente aries Ki j ete NipeA onsen oe | ie ee one pare Oe 2 Li igen ath me tite ee ate srvonttan mn _ f OE oe taza Ca a amet tq dtacersy Isoteyi i cee pa ike i ha a , Mud If sediment is mud (cohesive) this provides a lower bound for a normally consolidated sediment. If site is near river mouth, Miss., Nile, Amazon, etc., mud probably underconsolidated (Young - not yet in equilibrium with wt overlying soil, may be limited strength buildup with depth. Consult an expert for design advice. Much of the nearshore is -overconsolidated (greater past overburden than presently exist- ing) usually a desirable anchor- ing situation. Locations (e.g., glaciated areas, high current areas, tops of rises, passages). Unsually strong overconsoli- dated sediment could lead to less conservative design (long- term loading). Sobbottom Depth (ft) Note: Hemipelagic and terrigenous material is highly variable. Range of values gwen for turbidites will apply to most of the stronger soils (sand Layers of even beds are common). Occesionally weaker (possibly moch weaker) profiles may be found near ective river deltas, This curve is bused on tesns of about 20 cores ranging to 10m in length from the Santa Barbara Channel. Data to typical soft greater wbbottom depths are ban material from triaxial text extrapolation S,= 21804 Subbortom Depth (m) 0-37 deg cole kPa p+ 320 kg/m? at Om 10 640 kg/en? at 30 m 1 kg/m? = 0.062 bit dme 3.28 ft 1 kPa = 0.145 b/ia.? 2. Deep Ocean (Pelagic) Sediment Properties If deep ocean site is not an abyssal plain, determine if depth is above or below Calcite Compensation Depth (CCD). Topography of the calcite compensation depth (CCD). Calcareous sediments are found only in those locations where actual water depth is less than the CCD; numbers on contours denote kilometers below sea surface * ee ee oes Pome een Teo a er ee > aay VERA Eye ' ‘ %, “ nnd An ety = 9 ater oe 7 ne Lemur we rey —< sieve wa tteu - manele’ f 1 ap toe tm tom Scam wath * jf ~* : = x a de Vere A ee ioe i i / tah tite Sean | { Pelbeo) : i “och ee ramet | j a fd ee a Se ST OTTO ; we v ’ rs i my 9a0' pooh. 2° Seem agab rire Lt 4, (Gad) wae wilh AGIOS) er ater te AT AR Ate e119 mimeo 1iegkbae’ Gaagera) #3590 qvatt} ths mayo attsic) wolad cos hy neh pente ars exjates ah to \vetourpeqe'T dads teal si aqgob tare teagan gigdin BholvenGl caselt ni ‘ela aauties dae Whig eee p30 ahs co “08a ae Later 4.) Prin ay 00 kfeuaal "oe ike ,neorn bese ba “Steere eels io aged? a - stLieanibtee goorte yihel 0? HANT binds stcvmthes Satine gx anh, svisayrasgean ‘ (an ibaok a syo8. 06 FOS wi atid neese qa If above the CCD - sediment probably calcareous. If below the CCD - sediment probably pelagic clay. Note: Curves for coarse ooze are from tests 00 three cores to 10m from the Biske Platesu. Curve for fine core i baved on ursts of 12 10-m cores from the Equatorial Note: Curves based on vane shear testing of 15 10-m piston cores from the North Pecifc. Data at greater subbortom depths trom Subbottom Depth (f1) Pacific. Data to greater depths are based on trigxial best extra polation Maxial test extrapolanon 1 kg/m? = 0.062 thvtt? Imes 3.28 ft kPa = 0145 bia? Subbottom Depth (m) (water depth Jens than 3,000 m) Subbottom Depth (fe) typical abywsa) hill Province pelagic clay S,= $7 (upper 15 {0) = 3-5 (below) o 33 deg ca 3.3 kPa Jp 7 320 kg/m? ar 0m v0 640 kg/m? at 30 m 0°37 deg cook 1 kg/m? = 0.062 AT den = 3.2K fc 1kPs = 0.145 fe? 4p + 480 kg/m? at Om wo 720 kg/m? at 30m Typical profiles - calcareous ooze. Typical profile - pelagic clay. La (kPa) If location is classed as siliceous ooze Se einen te ae a ea | from the Equatorial Pacific. Data at greater subbottom depths from triaxial test fabrication. Whenever possible consult experts at a nearby oceanographic institu- ae tion for property data. gee ure are 10640 kghm? at 30m Subbottom Depth ({1) & Subbottom Depth (m) 1 kg/m? = 0.062 bit? m= 3.28 {t 1 kPa = 0.145 fin? 100 1 2 F) ‘ 5, (pm) Typical profile - siliceous ooze. Subbotiom Depth (m) / Sit asmmedioe dena J Att omen 89 A / eee Nh rine ee t | f ; A Lge mies ' ' i rs 60a angen ‘eos 7 tot te teed Beara / (Boe aunanesdem = hodt Lore | r i ry ; / aK beand®> ad netisoof { _ on j y 7 “i ' ih sss a pare a : | j | etysqie i ipeaes aidtszecg x8 ; pri ydvaen a ‘ad “al i Me ) ae | Baan ytrorong x0 | 9 i paeila j a id ena . tae " Ng | ; . et | by / eh t \ + be t haus a | is ’ H | VEL Mt u : | i fi een WN oaTer a j auosohite kro LaoLqy P, D. Hazardous/Unusual Seafloor Conditions - If these conditions are encountered or anticipated, caution is necessary - Design possible, but requires more detailed procedures than presented Examples of Hazardous/Unusual Seafloor Conditions e Submarine lava flows occupying a relatively small and irregular area. e Small sediment channels, local extreme bottom slopes, cliff-like topography, or giant seafloor ripples. e Erratics from ice-deposited glacial detritus. e Metallic nodules or "pavement" formations above soft sediments. e Sloping seafloor greater than 10 degrees. e Deep ocean siliceaous ooze (>30% biogenic and siliceous). e Clean calcareous coze (>60% biogenic and calcareous). e Sensivity >6 in a cohesive soil. e Cohesive soil strength varying by more than 50% or + 100% from typical profiles presented. e Unconsolidated or very high void ratio clays with c/p values near 0.1-0.15. e Thin sediment layer above rock. e Layered seafloors - soft sediment over stiff/dense sediment or vice versa. ory veto meatod onesies Abe | | Pa 8 age Blot avi mix POOL * 20 ‘Sas <4 ache aout, hal guiviny ve ae ale seam, asalay q\a d2tw weal, pide’ ‘hoy dann oy th twemtbon sano\thise vave: Samntivon 3. GENERAL FEATURES OF VARIOUS ANCHORS Deadweight Anchor Large vertical reaction component, permitting shorter mooring line scope ‘ No setting distance Reliable holding force, because most holding force due to anchor mass Simple, on-site constructions feasible, tailored to task Size limited only by load-handling equipment Economical; weighting material readily available Reliable on thin sediment cover over rock Mooring line connection easy to inspect and service Good energy absorber when used in conjunction with "non-yielding” anchors (i-e., piles, embedded plate anchors) .Good reaction to vertical load components; works well in combination with drag embedment anchors permitting short mooring line scopes Lateral load resistance low compared to other anchor types Usable water depth reduced; deadweight can be undesirable obstruction ei atacchsisntiticstat na Sen Plate Anchor High capacity (greater than 100,000 lb) achievable Resists uplift as well as lateral loads enabling short scope moorings Anchor dragging eliminated Higher holding capacity to weight ratio than any other type of anchor Handling is simplified due to relatively light weight * te Anchors can function on moderate slopes and in lithified seafloors * Me Installation is simplified due to possibility of instan- taneous embedment or seafloor contact Accurate anchor placement possible Does not protrude above seafloor 2,3,4* A Can accomodate layered seafloors or seafloors with variable resistance because of continuous power expenditure during penetration 2,3,4% F 7 : pet? Penetration is controlled and can be monitored Susceptible to cyclic load strength reduction when used in taut moorings in loose sand, coarse silt seafloors For critical moorings, soil engineering properties required Anchor plate typically not recoverable 1.* a ? F Special consideration needed for ordnance * Me Anchor cable susceptable to abrasion/fatigue * Gun system not generally retrievable in deep water (>1,000 ft) 2,3,4* ie Surface vessel must maintain position during installation 273% Operation limited to sediment seafloors Propellant-embedded anchor Screw-in anchor Vibrated-in anchor Lo Driven Anchor Drag Embedment Anchor Broad range of anchor types and sizes available High capacity (greater than 100,000 1b) achievable Standard off the shelf equipment Broad use experience Can provide continuous resistance even though maximum capacity exceeded Anchor is recoverable Usable with wire or chain mooring lines Anchor does not function in lithified seafloors Anchor behavior erratic in layered seafloors Low resistance to uplift, therefore, large line scopes required to cause near horizontal loading at seafloor Penetrating/Dragging anchor can damage pipelines, cables, etc. Pile Anchor High capacity (greater than 100,000 1b) achievable Resists uplift as well as lateral loads permitting use with short mooring line scopes _ Anchor setting not required Anchor dragging eliminated *Short mooring line scopes permit use in areas of limited sea room or where minimum vessel excursions are required Drilled and grouted piles especially suitable for hard coral or rock seafloor Does not protrude above seafloor Driven piles cost competitive with other high capacity anchors when driving equipment is available Drilled and grouted piles incur high installation costs and require special skills and installation equipment Wide range of sizes and shapes are possible (pipe, structural. shapes) Field modifications permit piles to be tailored to suit require- ments of particular applications *Taut moorings may aggravate ship response to waves (low resilience) *Taut lines and fittings must continually withstand high stress levels | Costs increase rapidly in deeper water or exposed locations where special installation vessels are required Special equipment (pile extractor) required to retrieve or refurbish the mooring More extensive site data is required than for other anchor types *True for any taut mooring. i A A IS SPAY OT Sia ae, odh mi dnie rent Tel COW any E) Aen feelin peky Geer wr dede's ey Aland fanabetod 3052 ee eiteh ines SOREE bys eeges Ketone Wh Spuks Dong o#y cde) eiiwega saya divenpteoe tipie sate Ty bina he tle shalt iableuns Me yn jithtio biyes goth wed a IMA etibonw. Deby NT f i eR ere eee hie Bn asetie, a ore a ween ui ea aangey i Naini Deus rads abaeirig we bobo todomh aldmel ri depera ter ai mite) ge) vock akan oo Soke Aire eg Howl iwon boveoMret md nbd esau See posh whedyma! 7 ee me arn ye ‘hea. 4 i 1), bi f) oe ‘a veh rremktaes hirree! ot aktered wolhvetie sinh ) Ale ad Hoven! my f. Citancee brdoum woes yy epee Yiigt' ab apenselaet waz j Poojdwer xe geihenl Ieheoahuan, weed, Sevan: Ha { ) \ 1-73 SA A I Rice 72h; epider .Sralioyig egemed ans tomas gai heap"? ia ivoadaset i | t i Rene iy i orate adi ant ean Leaynesehicaitension tea cdl SRN tins ty saline r Ahhh pee = er A ae A yt ‘oll + Hale soar! Se ie Ae anc eae (etre mae | ah : Let 909,02 alee x , SR Ve} a 4 r+ iF =), u 4 ‘ qate: FUGUE AT Ot Leveied 96 wosont whad i —— Saterammeaint: rion Lipide eit cea Jonas sony Ligy.d: ant PENA sa hip! eiiarhiven Aat OOO Gel ehh vase ve?) TAtpagen Mpa } eae t - y | | 7 ‘ . i koe Wa QIethivies ghee iasesa) 4 iav Steloe aleioe | 4 ) i nnd bt excedin Sxeita SU Cel Sete ere ae |: Ob hep ws Jive aon | } c watesaged ay We aL | basaaic poigues tataad ; | ity h '.5 a cS : APO OOTbWAL Te Baste Uh oad Siepad qeower els 2: a Rren int nel heh. Cie SET ea eee (ad. wile to ae Ser kp as Heh SONOS Mogren tems Fo. ap Bt mt PaKrae4 eu G i Hnreet pep tea aa ye Cexae Read i Hew basi Lie? ieee ged } BAL bee Poi Lett Nts, | v edie tern | vn We thyeney, roligna Syeda ie Me) | ee ae | role) lawn OD Vls26.pw. Mg atl 4 J ttéene Hey Q ‘ Ws el oy ea a] ips) (Or BARCEL Wa) 2h Yoo 1% era lier! i , F i J 1a ‘ae: : Pie H oy buabé f ma, ¢hee? GOidel lays Li { yatt hit belied i vey ‘Ae wh ried , ne * PA tee rU 1 | sia iwcwe. se jie ti | Tasapngess, , whic) STGP Ay whe 14 . ye WOW | LS eo) ae, a we rai i , re te ‘ RE ee OTe WA tema Baie ¥ > . ‘yy n ’ a ; heed Le ea arta ita ” " Ol tiee THR cwvoas , taye weal Oly BPTI O2 Behe f bie tarty 106 (ope NP Aeot a rin owntyae 4 bed y, ged hee tad | we Feo it boa eowall 2 ; iSeeeragut see vi v 5 4 Ly i ) sta u i rinvihis yet lisveer seb da monte ce ¢ ay b whhee heehee y vy } + hath - at he hal t PMGE owes } Pee aL TORAH OF ALNeTY 16 hey az oe " saa 49 % je Lwiova? , j = : eas ts to et, £29 de ael ea ae BD valn ae elinsdang! ae ae rm sea : 4 rie bine 1 | i notte] Peay yt haie ft tna einteo tu I hy ‘ mn I Weehithan sewetoe. ae ie ; vere A he tam emer eh rye tm Ves PLATE ANCHORS Plate Anchors - Summary of Types (Refer to Taylor et al. (1975)) Propellant-Embedded Anchor aA ys Touchdown Penetration Keying Anchor estoblished Anchor assembly Current Developments Primarily U. S. Navy developed CEL 10k, 20k, 100k, SUPSALV 100k, 300k - Refers to normal long term capacity in soft seafloor. e 100k anchor commercially available Driven Anchor Menard Rotating Plate Anchor Ee ee ' 1, Mud Wine” ne = kai NS ETF = VASO ES Vi The RN pte ot ‘ z Re : Driving 113 Le aaBhe mandrel 1! i of tee i tiie i ue i rd Vit os 5: h NB3 Ve ip J. Finol 1 ‘ ; 6 emplocement ~\ position: — AK o Y ) h ! t » Opening In-service oad Position after Enlorged perspective position position puli-out test Navy Umbrella Pile Anchor (current work in U. K.) rape fi a aq ae | | | (ceceny be ts y aya nt rail one te ome! | behivtoten witaad Grice ulinitens® awidesoo, usomagoleyat Jira IZ) beqolsyveh yu .@ .U ui buembst - AH0E ,AOOE VARI, AOOL HOR MOT L Sladabal ad trent gros Luarsoa ow Pea , tool lass ViHa nt sidstiitave yifetosaamos xédaan AGOI © Zora nh’ S38 09 got teres | Desa Vi} dey ert aah bom = REE OR RN Ts PAINS f ro one os { pen Aa Vert rege i aie” | sa Me gh Ry | \ a ey Ba | ei’ ; ag To’ y i! ‘ 5 " j a a » j \ “ Hi . A — . ati haem) 5 ! he | - fj | } .Y c bney oy A : tne ie ? oy Jay YY oe } Tit , % fy ff : yw + ; he : Past Spear . ii ae he iy) ap ) if / a0" he Ae asi enete sami *, ff A sary ated S74 ht “ ; qe egg 7 % * a teat “ug -tyee i a pent - wee alisrday Bite Inerr09)), Te (2) Screw Screw (Auger) Anchor er) Anchor Vibrated Anchor -One or more Anchor at base of long helices screwed slender shaft, vibrated into the ground into the seafloor; plate from surface or is "keyed" to operating at seafloor. position. Auger pin anchor. SETTLED SAND WATER INLET Jetted-In Anchors SEABED _ ORAS LINE LUG FOR BRIDLE WITT 5 7 VLLTTLE , BAC STORBED PRESSUR:ZEU WATER AIP. INJECTION POINT Sh Say Gj api yj PLATE i BOLTED TO ANCHOR Royal Dutch shell jetted anchor (Netherlands) PERIPHERAL JETS Hydropin Anchor (National Eng. Lab. U.K.) B. Plate Anchor Failure Definitions “S55 —— Deep Anchor Failore C. Plate Anchor Design Loading Conditions Short-Term Loading - An increasing load to failure such that Static in fine-grained soils drainage does not occur. Long-Term Loading - Uniform static load where full drainage occurs. a oak beaendtY Wie We nea ei gues to, mead da +0d0A boteadiv ;ttada wohmola oteiq preottase afi oak ne od “beyved wt okt aog, i ‘ 4 VE.on Aathiw 2S HOT qaetnd ROY Bue 4 7A < of): re | me Nah pee bettet Lads faded Layot | \ (gbasliedszen) tonona ie remrey Doses ni qork i hed. 4 .dald “% mek SE ot yoda veo sia GRE A anorlzihucd antigens Hglasd todorwad fedt dows erafist of baol gukenexdak oh .4uo90 Jon noob agéntath alice baategeemnee? sgsotexh [lot saadw Saol aktate erxcit Kal ~ JeRbRed exo T-gcigt | Impulse Loading - Non-rhythmic loads > static capacity, < 10 seconds in duration - sands; < 10 minutes duration - clays. Cyclic Loading - Repetitive loading with double amplitude magnitude > 5% static capacity. Earthquake Loading - Cyclic loading induced to the entire soil mass by earthquake energy. Dynamic D. # Plate Anchor Design Process (Refer to Beard, 1980) 1. Site Survey: Determination of hazardous/unusual condition, soil property selection, soil type determination. Pe Determine Anchor Embedment Depth a. Control embedded anchors (e.g., driven, jetted, vibrated, screwed). Depth = f/soil type, strength, plate, size, equipment limitations. b. Dynamically embedded anchors (propellant-embedded) Cohesive soil Calculate by method of True (1976) Cohesionless soil - Penetration prediction schemes are poor. Calculated Penetrations for Estimated Penetrations for CEL Clay Flukes CEL Sand Flukes ene goox | rook | 20x | mx | — Sand™ Soft basin soil 19.5 (64) | 15.9 (52) | 10.7 (35) CEL 10K sand/coral fluke CEL 20K sand/coral fluke CEL 100K sand/coral fluke CEL 300K universal fluke Distal turbidite Gay 3.8 (12.5) 3.4 (11) 3.1 (10) 17.4 (57) | 13.1 (43) | 8.2 (27) | 5.8 (19) Distal turbidite 5.2 (17) 4.9 (16) 4.6 (15) (high) 14.9 (49) | 11.9 (39) | 7.9 (26) | 5.8 (19) i 7.0 (2 6.4 (2 Proximal turbidite 12.5 (41) | 10.1 (33) 7.0 (23) |} 5.2 (17) TO (ES) (23) (@1) Calcareous ooze (deep water) 9.2 (30) 8.2 (27) 7.6 (25) 22 «(72) | 18.3 (60) | 11.9 (39) | 8.2 (27) "o = 30 degrees; y, = 1,760 kg/m? (110 1b/ft>) Po = 35 degrees; y, = 1,920 kg/m> (120 1b/ft3) “ = 40 degrees; Y_ = 2,080 kg/m? (130 1b/£t?) Course calcareous ooze (low) 19.2 (63) | 16.5 (54) | 10.7 (35) } 7.6 (25) Course calcareous ooze (high) 15.2 (50) | 12.8 (42) | 8.2 (27)|] 5.8 (19) Siliceous ooze 24.1 (79) | 19.8 (65) | 13.1 (43) | 9.2 (30) Pelagic clay (low) 24.7 (81) (68) (47) Pelagic clay (high) 19.2 (63) (52) (37) 10 Of cesta nerer2 < ome -eyalo ~ gokewiuh aetuazm OF > sake . ohns Fieve aidvoh ttw guiban : vaig esisne aa au basobat athe (oBer bread 3 . Scmihiye ixte stele yee i (babbedus-tnallagorq) enodynd’ te t {Ov@l) seut 2o)% acmuiss editotberg soktexiokss =) 0 40% and biavtnast Aagnmi sed a * aovgis baee i a eS a ee ee): nT ee ath mer peyyhawn ppemumnldnenmagie slays ; + 42 jad) « enhaen mine ssitad t canoetememmeaalinaudads ine otons a ory ie pana autbet ; tien weasel i : \ nen Staak , said | e be pte coe Sree Wea i bart 3 ion) 1.4 tty > ah a2 aol af 1) Matt: Ivianhees yi ‘ i no itty oh 8 esc a 6) 9 Fr £9 Senor iba” oP Ree ad dusty 7g RL H. 40). Card Ash (at day eb) & Woy MR) : | ; | iageatdetataed visconti teas) oo: Pa! $1 RRR a RAY Bat © 4.4 to) 4.8 (ary. $.¢ : me a yy iB i tga teat 54 618) pei iets ub Gh ey cy ae? I m ao aes y ae ea I ; ; Merk sh "Aa Fi . * ve . 4 ’ 1 a eth OF ¥ ey tK0 i ti) they gat é —— iW yoet yt seeripa Ae | : { Seve (es) fy dee, ¢ © es 4 } th Wee IRR We See iT FMRanen Oe 4 oth) eae lay a fo adi +) en sth ye oy ist eur! gay ee on ‘ t eta A ilas hinalied herr : | rey iy 0) Paty Pt 4. OY. * 1 Sabtabad pa Hi, Of Ge Anchor Keying Plates embedded edgewise are "keyed" to assume horizontal orientation. CEL propellant anchors key according to: D, - 2L (L = fluke length) D. - 1.5L 1) ” (eoineatsse) ” Cacoationticas) 3. Determine loading condition, calculate capacity. a. Short-term static holding capacity (no drainage). Shape factor (Skempton, 1951) s '* , i Be = A(c No f + % D Noe. 84 + 0.16 B/L) After Vesic (1969) with disturbance correction factor (£) by Valent (1978) where F = Short-term holding capacity > | Projected fluke area Soil cohesion Disturbance correction factor 0.8 - terrigenous silty-clays, clayey-silts 0.7 - pelagic clays 0.25 - calcareous ooze (validity of this factor in doubt) y Buoyant unit weight of soil D = Plate embedment depth B Plate width L = Plate length N. = Short-term holding capacity factor-cohesive soil N = Holding capacity factor for drained or frictional condition 11 ae ce. ee = eee Ca | | ay, ‘ Rae F fasaexixzod smieasr 22 ‘ot cin 3 a cin seater a0 (Ateosl. sdalt = 1) 45 pi 2 Aout me fie Ag : . ieee Tet + * (ogghaoiedas) edi auqes sieivaied nok see gathuas mrad (egeniexb oc)-ytivages gokhfor abate was reotie todza? ogede {T2OL , cotomaday) a ne a (J\@' 8.0 + #8.O) ae jp oot pao aMtoRt obra Too (OseE) anelav yd x yriseges, gaphlot arx9g=220888) = as e274 aul? tossetasd Fy 8) dairies (Eee ar soJ203 moksastxeo sousdae tea, e aglin-yoyals yaysio-ystta auusgey tse SOO & ayals xkentad: 4 et Milad (tdgob ab yoiae2 ekdy to ysthiLev) 9200 auesmas lew + ea [ioe do sigtow Fran Bi dtged suawbadng ‘s¥n ft co Eitrhiy ‘apets digeat Sie = lion evkusdoo-votoad yirseqeo galdlody mxndeanints 2 {unolgotst wo baakexh sok norses saa va ee "|, if Molding Capachy Factor, Ni. 4q Holding Capacity Factor, f F. (Cohesive soil) - Nowa. 4 Neglect Yb D aa te F_, (Cohesive soil) = A (s,, N. £) (0.84 + 0.16 B/L) Fat (Cohesionless soil) c = sR 0 Be (Cohesionless soil) = A Vp D N, (0.84 + 0.16 B/L) Short-Term Capacity Sloping Seafloors Refer to Kulhawy et. al., (1978). Short-Term Capacity Laterally Loaded Plates Refer to Neely et. al., (1973). - Plate anchor capacity is enhanced with lateral loading. - For propellant anchors, keying distance is minimized. b. Long-Term Static Holding Capacity (full drainage) - Time to full drainage = f (permeability load, drainage ; path, anchor size, shape, etc.) Cohesionless soil - drainage almost immediate Fit Cohesive soil - long-term capacity governed by drained strength parameters: friction angle, 9, and cohesion intercept c . —_ (cohesionless soil) = Fit 12 (t\a ar.0 # 88)B) a Ri go = e (td ald + 98,0) 7 goitbaol Tazoset doiw basnaihien ad -besimigte at sanedeih gabysd (oganterb Lia%), yrtsaqed | egecterb: ,baol yailidpsmreqs & .* (.o¢8 ,ogeda ,oate sodoae diag “talhemmr Jeonto sae r djgssite beotesh yd bentsvog yiroaqua Oe 9 JIqseotesnt zolesdos baa, , siges ao ) Of Holding Capacity Factor, Fiz 1 F ‘ (cohesive soil) = A(e'N! + Yb D N) (0.84 + 0.16 B/L) Fi = Long-term holding t q capacity c = Soil cohesion intercept A B, L = Refer to short-term Up) AAI : section N = Holding capacity factor drained/ frictional condition (Refer to short-term section) Ne = Long-term holding capacity factor for cohesive soil Loose/soft seafloors - failure associated with relatively large displacements; retake” GY 5G piv 1/Sio CS B//Sie", ¢ = tan “(tan 2/3 $6) Creep rupture - cohesive soil - increasing rate of shear until failure occurs (poorly understood phenomenon) - Problem appears minimal for calcareous ooze, pelagic clay. - Fx S = 2 adequate to prevent creep rupture. c. Dynamic Holding Capacity 1) Impulse Loading - refer to Douglas (1978), or Beard (1980), for details of prediction procedure. Consider only if large infrequent loads may be unexpectedly applied to a plate anchor mooring. Can have a positive effect on anchor holding capa- city for loads of up to: e 500 sec duration - cohesive soil e 10 sec duration .- cohesionless soil For load durations < .01 sec impulse holding capacity can be: 2-5 times short-term capacity for a normally consolidated clay. 2-6 times short-term capacity for a mid-density sand Impulse loads near or somewhat above Fit can be tolerated. 13 f / rel (Tie. OL &, 0G, ‘& a af + wie antbtod ees~gna) = art “tEsaqns. nekesdos thot = Te Fqooresd nt a “eentttady og aie 9 2 8 yy kD p RohII68 Vertesqes gathicdt = Ov ‘henierbd 10750 ° aesdtone> funokiot23 @1Ss-Iefe of viet) (aatsoas qaihtod wros-pdel & TO} ¥oJoat ysroagas Liou avieados And Ylevisates dstw betatooeas sialtet ~ oe « 2t\s * 2 tt vd is «2 Sauber ba Lideu aaeda to sem gataworrek: a pion: (nogaitionnly boutersbas ¥iie vals oigeleq .aano auosyeotes 20k La -PIUIGY Gort Drerany Os | bused so, (OTOL) balgucd oF sate4 - rtubsookd-oobsaebang Jo elie ad yew aboot tnaupextgl sever 3% Vian’ .Qtiiteor s0d0ne atalqow ot betlaga yibey “niger stkb ios. sodond ao Jostte sy ii igog ge: . rod qu to absol 30! ; tins oviasdoo + pelieavh Sua OO eal) {ioe expinalandos.r . agktarwh ome | i oe! antbiod selnqut sea I), > dootieueh Gis ad Mao NSB aileron 2 x0? Ytiosges miss -pyade weil? ee8 volo batvebhtoaren,, Vitoreb-binm a yok vii DatRg wrod -s2Ohe womtl? ang hake od ano , 1 swede Jedvanoa yo se90 wei ir ‘4 3 2) Cyclic Loading - Refer to Beard (1980) for details of cyclic capacity prediction scheme developed by Herrmann (1980). - Caused by wave induced forces and cable strumming. re 3: is double amplitude cyclic Bz 50 lead component ce SS 2 - Cyclic loads < 5% static capacity of no concern, therefore, cable strumming can be ignored. - Cyclically loaded anchors designed to preclude failure from liquefaction or cyclic creep. Ne eee ee Accumulation of small movements Characterized by strength loss and that reduce anchor depth untii pull out occurs. sudden anchor instability Strength Loss During Cyclic Loading The following procedure excludes soils such as uniform fine sand, coarse silts, and some clean oozes which are susceptible to true liquefaction failure. Use of plate anchors in these soils under cyclic loading is not recommended at this time. 14 fateh 20%, casi brant ad. satof s: ‘a beqoa loves isons ae . to gokielimginoa azrousvom! Eien Semone Soubat gaz) ifaq Litas d3qe} etues0 Jue: a EY VR me aakbaot oi toe) gatrag sort motion aa dove allow wabdtoxa skubyr: org yoben (de air 09 aldrigaceus ors moidw eonoo neato ouoe ba6) artis Sa allow saedy ak wigdogn sfafg to aely aay ax oaks mt (% of static capacity) Double Amplitude Cyclic Loud Procedure Determine te from the soil permeability. For the assumed sea conditions, determine the number of loading cycles during t_, found from the soils aerner pei fey. Enter ‘the figure below to find the loading bounds as a function of soil type. This table can also be used directly to find the limiting number of cycles for a given loading. pala : =o ' c ep oes 90> Note - Cyclic limits apply to anchors with = + | an average quasi-static load of bess sot than 33% of matic capacity. 4 | 70} 60 1 40 207 i 20+ 10} o—__— aE = na = 102 103 10¢ 105 108 107 Number of Losding Cycles Cyclic Creep During Cyclic Loading - Poorly understood phenomena that does occur in the laboratory. - Number and magnitude of significant loading cycles occuring during the life of an anchor control cyclic creep. - For cases where static load exceeds 20% static capacity, add portion above 20% to cyclic component and proceed. 15 Time Required for Dissipation, 6 107 10% 10? Oo 10 = ao) ao%) aos) ao% = a0) ao) a) Soil Permenbility, em/eec (fthsec) acl, aol) AprxoximaTeE RELATION BETWEEN CorFFIcIENT OF PERMEABILITY aANp Grain SizE Rance | Size at which permeability is measured, mm Limits of mits Cocflicient of permeability grain size, Soil type 4 0.6 0.06 0.008 Double Amplitude Cyclic Load ( of static capacity) Note - Curves give upper limits that apply to anchors with a quasrstatic load of from 0 to 20% of static capacity. 103 10* 105 10° 10? Number of Uniform Loading Cycles a pth tp nap ead? OH! \, XX 4 ] fat ‘, ph iy, ’ ~ %, , , eh i a 2. ao an i , ay . “— na he eat rama on roo * ia hh exer 8 id i F rpaewdl ppvverell walter fie! Vs aes Torey? woe it ak dian) ans sinter teen aN Sst: amas nati dja Ce cubis We toad | nptatdentres te aleonkl Pee te 3 eee orem et ¥ a 3 men a 3 nto j me ava nie brs | nan hia L ee oes neuen wid owe warned ‘slg i wy 7 ‘ ‘ q 1? eee oc } i ; «2 eer Fhe y ; “i a oy : rae, > ! ae : wit ‘ ee 1 hedlunte ; i Hs , ma A t sah j j i ee ee ee 7 i ro! ; woe : ye? - — on a yamine dnaitbenippesiglitons 4 co - eye Oe me my 4 acieees ‘ BS rote SIO aRRR Baker} arenes ea OO Ai i790 aooh , f | 1a iin Bake Su: ali te j | i/ ” ‘ - pnt nia aa a i ly Ene? 4OOoie | #] ‘+e | . Meat anand | 4 Pte it 5 ise atggse WS abesd . i/ Pal 7 ni Paton aa ROS ‘avude migestonte de ae. ‘tie Ae tay ‘Soren bara Gane - oe ‘ ” CAPA reel wry > cee — " a om rately He ~~ } ery j Mi why 4 wi ron v + { ~ 3) Earthquake Loading (Refer to Wilson, 1969) - Cohesive soils not susceptible to significant strength loss during earthquake loading. - Granular soils can liquefy during earthquake loading. - Granular liquefaction is a function of soil rela- tive density. Potential for liquefaction is illustrated below. Standard Penetration Resstance (blows/f1) Standard Penetration Resistance blows/fr) Depth (1) (a) Maximum ground surface acceleration « .15g (&) Maximum ground surface scecicration = .25¢ Liquefaction potential profiles for earthquake loading of granular soils (from Seed and Idriss, 1971). Maximum ground accelerations are a function of earthquake magnitude and distance from the quake epicenter. ximum Acceleration - g Ma 0 0 20 Ba) 60 80 100 120 140 160 Distance from Epicenter (km) Maximum acceleration associated with earthquakes of various magnitudes (from Seed et al., 1969). If analysis of the site and its expected earthquake indicates a high probability of soil liquefaction, the site is hazardous. Use of plate anchors which are loaded a significant percentage of time should be avoided. 16 (Geet (wou fav ad. 91 00912. pe sitkiges: whnuprtrsd 4 ‘deepens gar sarh seme ~alat lies Be mettonut 6 a4) 40 wt st matooniascai tee port tytn a ; ah iahieasa ae aiios. lark aueiray yt + RINE 4 tae Te bose ane data s catavibak sdacpdtaee bagosaes aah Dew: ie az %o ateyt sjalq to ond =. evobrayad wi ILE yr oupes pe ty) ad bi aside ants to spetteoxsg, fagoe ate ink * an j DRAG EMBEDMENT ANCHORS Anchor Descriptions (Refer to Ogg, 1969; Valent et al., 1976) We Standard Drag Anchor Significant portion of anchor capacity generated by anchor wt. - Full embedment-rare. - Develops peak capacity with minimal drag. (a) STOCK (ADMIRALTY) ANCHOR KEDGE TYPE Average Lateral Load : Capacity (1b) Weight (Air) | Weight (Wet) 10,580 27,300 | 27,500 11,900 | 11,700 Mushroom ae {b) MUSHROOM ANCHOR mud 2 Standard Burial Anchor - Achieves most of capacity as a result of soil shear strength. - Designed to improve their capacity through dragging to cause embedment to deeper, stronger soil. - Most anchors in this category fabricated according to rules -aoceve_\*toctmeent of geometric similarity where dimensions 478 proportional to (weight) Standard burial anchor per- formance is idealized below. B = fluke angle ll = shank angle + 6 =line angle Sa) Lgl a i. 3 & ———- ee 77%. e > ail = : <) <6 i eG a. placed on seafloor b. flukes keying c. in dense/stiff seafloor d. in soft seafloor into seafloor G+ 0° to 15° @ =- 20° to - 45° 17 (c) MUSHROOM ANCHOR - REINFORCED CONCRETE (4) PEARL KARBOR CONCRETE ANCHOR Standard Drag Anchors. 34° FOR SAND BOTTOM OPERATION 60° FOR MUD BOTTOM OPERATION a STATO Mooring Anchor ae ied iW i ant = PAA Mai NE Je | Novak tye wahaend 1 yaingoenrh-ahismeptin de arr hee Ane sodond Ly seed : ag yrkueqes to seo 4 aK : weal how Sa sdedd svorimt ay Qotgaanh dyson (Soyae0 62 tiegotoo abil? oF saae wo live og git a pay. Sxedy Yo brain ey tsnolsroqady. bites cot RY € verily 4 . y “Th ene Tgkvard b ee Bs \ \ eB al 7 ae Lod ‘bow Loeb i: at \ ase len Se 5 . sf sy \ — ¥LAPOERD fy Ce ee 4 bay a 4 f 4 ‘ \ F seat ae : en u Ay oectp i A ys JD : fj Vag i er it = p ‘ mations, gatwnudt OTh 0 fi ee Pe Da a) ‘Wns woraPame tion int! d % fn) Mange ah ; oaocaehe g rere RBI + ca PIR ~ ves Mal aT NY | Linea il? ay Idealized anchor remains stable and holds stably even though dragged (achieves equilibrium). Pick Type Burial Anchor - Anchor designed to turn to penetrating position even if \ dropped on its side. Cast Bruce Anchor Twin-Shank Bruce Anchor. Mud Type Burial Anchor - Permanent mooring anchor. - Designed to be control lowered to seafloor. - Designed for very soft seafloors. Doris Mud Anchor 18 . nF bt . ae i : ih ii ; i f j , i, eae ae att : = i Vea k to eae boygnrb Aguodls avs y Lfodd abteeh mm aeainga of t ; 1 69 atut of bangin TOHORA en NY it move nolitaay. sabia eg) fh ae Shee at? go Heo e hy my } i o z a m~ Oia ee Hig : ronuna 5 suryoom IoeusarrsS OBo0k Loxvtno> 2a 62 Berges = soot ase of Herawol YRIY ‘O% bang lest sake ons ey adic ! Myers pes ile eTOO 1 TASH og Peer a 2 — Bt B. Anchor Performance Ie General Behavior (Refer to Saurwalt, 1971, 1972a, 1972b, 1973, 1974a, 1974b) Seafloor Type - [Performance as defined by broad seafloor categories. ] Mud or silt - Wide range in anchor performance; "mud" strength varies considerably. Sand - Performance reasonably consistent provided anchor penetrates; dense sand can be difficult. Clay - good holding capacity. Coral - Function if anchors snag an outcrop, fall in crevice, blasted in. Rock - Unsatisfactory. Layered (sand/clay/mud) - Performance erratic for high efficiency anchors. Roll Stability - Anchors improperly stabi- lized will roll limiting peak capacity. - If an anchor rolls in a mud or clay, the anchor will come out with a "mud clod" fixing the fluke preventing re-embedment. with stabilizers without stabilizers Eo - Erratic/poor performance can sometimes be corrected anchor rotation - degrees from horizontal by extending stabilizers . o--0 11 20 36 65 122 168 180 0-—0 CG 9 1h : holding-powor of anchor - kips 0 20 40 60 80 100 120 anchor travel - feet Performance of 18,000-1b Kavy anchor witn and without stabilizers SECTION A-A STEEL PLATE \% PIE SECTION Navy anchor. 19 NOs 6ST RE et ante sates igen me : , ait0ORAsnd 40nd sor aa ‘x@ beaiteb Wa a re het" ohm tate Woetsitie ayid ro? sites asaenuotae *' ehdate ¢lraqoide sxodsgd, « gutdinil ifox {itw berti -YJiseqas asoq te \ @ at afiga sedons ca 71 + a | wettone add ,valo zo bow foe" « uistw tuo send ILkw “mutt ef2 gatxtt "holo _dusabadiarsit gaijosvery i eon hice ay 44 b Da epauazolray voog\sitersd + a ae” bassearxon of asuksemor aso pits ; | wees itdwsea galbastze 4d Lasik 21M ema 8 “99 ai m,. et ©. RBs ost ait. see " ih A iN i Raa HE! ° by WENT Maite ShaMdew hem nzzy, 2 ince vf! int Yes ath H alan IOfoAe YyEh Anchor Weight (kips) mod 0 sand Mooring Line Angle Effect of line angle on mooring performance can be significant. 100 200 300 Holding Capacity (kips) Holding capacity versus weight for STATO anchors st various mooring line angies. Majority of decrease probably attributed to reduction in chain capacity. Fluke/Shank Angle Figure shows significance of fluke angle on anchor performance. Optimum angle for mud (=50°) Optimum angle for sand (30-35°) 24 Holding Capacity (kips) S v 20 30 “u 50 Fluke Angle (deg) Test results on an 18.000 pound Stockless Anchor with stabilizers in sand - Figure illustrates problem with excessive fluke angle in sand. USE OF EXCESSIVE FLUKE ANGLE Ih SAND Mooring Line Type (Wire Versus Chain) - Overall mooring capacity ~ similar assuming sufficient sediment for complete burial. - Anchor penetration in mud significantly less with chain mooring - less sediment required. - Anchor drag distance to peak load less with chain mooring - as much as 50 versus 250 ft. - Anchor stability requirements greater for wire than chain mooring. 20 Yo sonactitagia aworlk sringth e 6% 0) as sonem@oting todses oe a ave: ail 9) Wot f (908s): bam 303 sigue euigh & = (*26-0£) baat aod aligns cine age en) F (fe. An ET Set ¢ gen Ti, an 2) hie AL i J et ‘ SUR DSO RUN eet see eee ee aoe oe a Seal wore: —_ . ferent 0 emia ag yo i yah hale | .: DUO omll de untied! bien gd | od ak palin aay fees (loa iAare: moldorg sutarsent!i wxug2t + Thiakos: syaorasd’ slann stat) svlansoxs adiw ntads @1 worduches 09° ie baew ok Miata, 7: eS | ae eee hy ne yor if iN ee en nad on (tind: etiamal ox tl). sey sat q 3 Tasaibsg Soeloitive gotovage wslieky « "senate gotrocw flere . a tetoud 8 29lqued Same tiiges he me Gellerjeneq ona : Ret iepa? toonibes aaa 8 ~ yalroom whats daw mest baal Ase ae amet sath «ogame ‘oe GOS awaner Of aa as gottona akats gags ortw sok w6deong abheneRtee Iblis ss oe gitszcom ateds daiw seal eisues Anchor Size - Small anchors (<3,000 1b) often exhibit higher efficiencies (by as much as a factor of 1-1/2 to 2) than anchors 10,000 to 30,000 1b. - Manufacturers' claims of constant efficiency with size based on geometrically similar designs (dimensions ~ anchor wt '~). Data do not support this as a general rule. Refer to section on Anchor Capacity. 2. Recent Anchor Performance Data (Refer to Taylor, 1980a, 1980b, 1980c) STATO Anchor in Sand Rotation Angle (deg) Standard stabilizers 37° fluke angle B. rc 18-in. stabilizer extensions 3? tuke angle oXo C _, standard stabilizers XK 3° tiuke angie total deck loed ~~ {anchor load + chain load) —— mchor losd only Load (kips) 20 Anchor Drag Distance, ft Test resuits for 3000 Ib STATO with various modifications - dense sand, Sen Diego. 21 t ne vd) ettongtoltte sengid yididee aeath ane df 000,08 of 000,00 exotsns ‘oudd (2 4 She ; ng siya «tog dyke yoaetaitie taasanos te atoll tw sodons « agotanoms) pene) wt ee ‘aseeean OF 39%8H |. ahoy sila e = MORNE AOBRE |r0fyKT oF zoket) waad onset Seaton neil | (eens 7 et iow re OF) ATS va ONE oO chee PCT ira saat int ts STATO Anchor in Mud - Graph shows trajectory of anchor embedment in soft mud (Puget Sound). - Extended stabilizers (about 30% increase) needed to maintain stability (6,000 Ib STATO with standard stabilizers rolled during embedment ). - Majority of load carried by chain. mooring efticiency = Zi° tension on deck {includes chain and anchor load) * chain dra on botton subtracted from deck tension to calculate efficiency. Tension, kips anchor (alone) efficiency = 10.5 tension at anchor C=16+ 102 C= undrained shear strength (psf) Olstance Below Mudiine, ft Test No. 23 Anchor Type: Stato with 18-in. Fiuke Angie: 50°, movable stabilizer extensions Anchor Weight: 3500 pounds Stockless Anchor in Mud Sinekless/Anchorinl nud A - 9k stockless w/stabilizers wAlixed flukes R i Hy | Load (kips) Se Chain Capacity (Refer to Cole and Beck, 1964; and Taylor, 1980a, 1980b, 1980c) - Chain efficiency varies considerably for "similar" soil types. sand - efficiency of 1 to >3 depending on density mud - efficiency of 0.4 to 1.1 depending on strength and clay content. ; 22 Pa + pe ee w cL - ay. od of * ‘ee So tema be Seep ethereal re wt el 69) *9 (Oe) Agee Lee one Movtecnely= 4 ai Gh ay tenet Gigi a3 sodoan aan ee ee Ai eaten (* 6 y 5 ( PPD don >... { me) Targte awes om ty ee ee 2 sealants Dt hha hp ee Yarn oe ; +} oun, oo “th ie on pe pv ow a “a 7 7 ae < eet be e [e. a eiige ' h ae ae Te i ta “ ont ‘anaes ew my me dn Sha os miaialenanamets Yeti qa? weber volyeT bas :A0Of dood baw eled oF 7 ‘ seqys [toe “seliata” sok yidsiebianes tatu Woesio ttt vtinasd no -gathneqoh £4 af We qameisitie - bes digosate no gaibaeqeb 1.1598. Be eeiehtte + ~ Bishi wats 24 we _ tot Al Didone? wiae eel , OORE os » akan 4. Tandem Anchors (Refer to Taylor, 1980a) Option A - Shank to shackle technique; good tandem capacity; chain should be lightly lashed to inbound anchor crown during deployment. Option B - Crown to shackle technique; slightly less efficient than "A" but easier to install. Option C - Ground ring to shackle technique; less efficient than "A" or "B" - relatively easy to install in shallow water; Anchor B installed first. GA. CAN BE FIXED OR MOVABLE FLUKED ANCHOR. IF STOCKLESS Se TYPE, FIXED if REQUIRED FOR PEAK PERFORMANCE. QUST BE FIXED FLUKE AMCHOR . RIGGING METHOD FOR TANDEM ANCHORS FOR ADEQUATE PERFORMANCE. Sc Options to Improve Poor Anchor Performance Problem Possible Reason Solution Poor mud performance - Flukes not tripping - Increase size of tripping palms - Weld flukes in open position - Anchor unstable : - Increase stabilizer length/add stabilizers - Unknown - Add chain - Use backup anchor Poor sand performance - Flukes not penetrating - Check fluke angle; reduce if > 30-32° - Sharpen flukes Anchor unstable - Extend stabilizers - Add stabilizers Unknown © - Add chain - Use backup anchor 23 (sO8Rt al akado (YI boeqen mebued boog p90, golib awegs yodoun bauednt of NAM add Jourotita ean jauplodaas ‘6 sido viasewpwoliada of [fusagk oF tesa ‘Sen ee pyre a ny Toad ae SES aes Wl ~~ . —=™ 7 oe ® . J "2 aS a ee ee op vb OS et at SD ele : = Me wn | “ hee ee Pe a ST ae ‘oar > “eS Cte aS SS prea? care ‘ ar ia Tasty —— ‘ x = = oa < ~ = _ eae eyes Jahan wonseretre, pod sea x00 aor oF snotead) * ti ne ; ; i aaisuloz noaxek a dnwebd $0 otke caasionl - stewie $ aloes Shh yotanes quand ag. ES Methods to Determine Drag Embedment Anchor Capacity 1. Method of Cole and Beck (1964) - Verfied procedures relating anchor capacity to soil engineering properties not available. - Available procedure dated to Leahy and Farrin (1955) is reasonable provided anchor test data available Anchor capacity relates to anchor wt as follows: pS © i P a Where F = Short-term holding capacity (lbs) we = Anchor wt in air (lbs) C,b = Empirical soil constants, dimensionless - Relationship plots as a straight line on log-log plot, C is the intercept, b is the slope. - Results valid for that anchor, mooring line type, soil type. OPTIONAL- PROCEDURE - Perform single test, use b = 0.75 to calculate C. ANCHOR HOLDING POWER - LB - Extent of extrapolation of this procedure questionable. - Theoretical limit for b is 2/3, where steel stress is yo 1000 10, controlling factor. Refer to SRCICR ENCHU Valent et al., 1979. - Use verified manufacturer data to calculate C for b - 0.75. 30,000 2. Prototype Data - Refer to manufacturers for data; data often based on small anchor tests at unlimited drag (request details of tests). - Data valid for specific test conditions; anchor performance very sensitive to conditions (use data with caution for other conditions). Sr Full-Scale Pull Test - Most accurate/costly. 24 erage Isat heslohen eh telah a ad Pe Ta a ~lgeat a MOIOE HeMIEEe? BGAAEE overturning moment Cyclic Loading - Effect depends on magnitude of cyclic component relative to the quasi-static load as well as the absolute load level. - "Porous" deadweight may be less susceptible to mooring line transmitted cyclic loads because drainage path is shortened (pore pressure dissipation occurs more rapidly). - Refer to section on plate anchor design for added details; also, see Foss, et al, (1978). Other Design Considerations - Scour, slumping, wave induced instabilities of the seabed, earthquakes, wave forces on anchors. - Degree of attention to these depends on location, water depth, soil type, soil degree of consolidation, seafloor slope. b. Anchor Design - Cohesionless Soil ’ - Anchor designed to realize lateral capacity (R,) according to: 2 = = h-5° R, = (W F) tan ($-5°) + 1/2 iS Vp 25 B where: W = submerged anchor wt (F); F, = uplift force (F); @ = effective angle of internal friction (degrees); = coefficient of lateral earth pressure. c. Anchor Design Cohesive Soil - Anchor designed to yield lateral capacity (R,) according to: R = s A+2s zB 1 uz ua 28 “at ReaNIRE Lanion se e tt 100 as2i4a Jokwstad ; 4 20.0 “xobau bas xnHIn soibex aq QUtewIsave Ihevoty 93 bsay she sai hanes iwol sd bigode stem Bay worl ad bivada: Sviveles Sissogmo> ptloys to et om Beal, adufosds add we Jiow 24 oom od oldlzge neue sual wd Rt dseq gua aeunved abiol py Creer styihiget sie8 wre aoldagiuein exuat jwileseb bohbs aol stint totes Sialg mo wily Ro aukzilidatyen? boanbat eyew, aigdans no eoa10! svew me tase, ,gokiaso! no aboaqeb sted of waxes r9oltase ,Mottshiloancs to serveash [ise pages [io® ynoladbsqdo® + mkaee aosak sem C,8) qsineqes [sxsdel oxitaey og bong task medowA. - +n PREG i6006 M BS gt yk S\tit (8h) mae on (CH) soxet. git, = Re (%) 30 xodons bag remo * " +oredw j{ses2yeb) metiots? laorstat to olyae svtioetis) «> & wxvegerg aituss Lasetal 2o Sasrattiean) = I [hoe sviesdod male ods rh fiot avisedod ggeaat sodonA 39 (OF YRtheGoos (A) ySineges Lavyel blety od bengkeeh yedeaA ~- a aut eR eat” a * soil undrained shear strength at depth z (F/L*) average soil strength between surface and z (F/L?) anchor base area anchor or shear key penetration into seafloor (L) anchor base dimension (L) 29 GUND 8 dag 36 dogma (S0\2) ai hoe edotane ‘gomwasd. oot (i) 460f3ove ot cotter temed eam. DEADWEIGHT ANCHOR DESIGN PROCEDURES mless Seafloor: Deadweight Anchor Design Procedure Cohesive Seafloor: Deadweight Anchor Design Procedure Item Equation Step Item Equation Loads Fy FL (given) a Loads Fi FY Soil Yy $ (given) b Soil By Si» Y, versus z Weight (in water) required Fr, c Anchor width: 2 to resist sliding w =——>_+F i WY tan(¢@ - 5°) without shear keys B= = uo Anchor width (min): ONE ie ith shear keys® Ry = Ba 0.2 with shear keys Sd —————————— with shear keys 5 es (s+ 0. Oo?) y.W-F -0.3F) s v h d Shear keys 1/3 200 s 6 WF. E h number, n n= +1 without shear keys B | 405 + % B Shear keys” _ B 405 + Yb B 1/2 200(W - F_) tan(9-5°) thickness, t eS Sat f number DS eee reat : b K_ y, B pb 2 weight per shear key, W W= Oly Bt k k k 1/2 3 ¥, B 2 thickness t = 0.042 ¢ Bs b embedment force for one © qa=9s tBt ue. W e uz 55S k shear key, a, t weight Ww, = 0.05 ¥, Bet e Submerged weight 2 embedment force for one ¥, B . Pee shone bos a, = be [20 t oe + B tan(@ - 5°)] (1) to resist overturning: (a) for H = 0.2 B, Maximum pull height W = 1.2 i + F B(W - F) aoe 0.18 with or without x, Sa ae ERE HEE iE (b) for H minimized, we ee FB as z= 0.18 Gen & shear key penetration = 0.05 B. s a io BAY = 8 feients of Passive Lsteral Earth Pressure, K , Miveight Shear Key” (after Tschebotarioff, 1962) (c) for H minimized, F z 2 v E 2. =0 ways 6 F s 8 qo h z BAY, E Submerged weight (continued) é (2) to embed shear keys: (a) omni-directional anchor We= 20 a. (b) uni-directional anchor W =n q. where ; umptions: a. shear key wal] is vertical 2 b. soil surface is horizontal o 5 to 38 2 2 YO 3S 5 one B ena " c. li “cohesive, © =O _ Be ool shearing reuntance & ecgrecs =9s =o 4. angle of vall friction,“ = 0.56 aaa cae te uz 3S. k Bearing capacity factors for shallow footings "Assumes cutting edge penetration = 0.1 B, anchor square in plan. LIST OF SYMBOLS Fy Fr Horizontal and vertical R, Anchor lateral load Y Submerged unit weight of load components resistance shear key s Soil undreined shear 8 Soil undrained shear Y Buoyant unit weight of ¥ strength uz strength at depth z 8 deadweight Ss. Soil sensivity Sua Average soil strength ¢ Effective angle of between surface and z internei friction % Submerged unit weight of soil z Anchor shear key Ww Submerged weight of the penetration into seafloor anchor B Anchor width f Allowable steel stress K Coefficient of lateral a4 Undrained shear strength P earth pressure at seafloor surface Z. Shear key height AG Coefficient of passive 30 lateral earth pressure riobqniy) Kgehedl predboyd fay tyr madeyg.l * sy? tidal vig? 1! i y aM ha (he * “ay + age P| * hed eh > i DL. a rs - a" 4 a’ a He " —- }% a gf ¢ iv ‘@2 me ih. F . P H o " * 13,8 cael “a @ sie -. r Sa s a ae a7 ° bog wv ; e 16 beating e 3 ai x ae oe i a. ~ t ry wey Wl ween Soe , A 1.6 * ‘ ' on = | io tae ¢ aan 3 ‘ga £oa4 at ¢ ati 42 j Uo ane BIG nr tive . uf ‘PAS petite 2 Hottie SOR Ny . ie Thebes Atay "soul Saude Py mh, Kee i » Pahads icy 4" 4 tom fends tag piew ay ek voted Deyepoion =, a YS deeds os dyivs Odg teeing r gilomrieere gihawa oF iT) 7. y 9 ead | Ly ee bontwi ain W xed te ‘0% 4 4 eps eay YOR Lv} a Poet ferry) as Tunweron gee (a) mood Cnmabs ned tie fom be At oreo ill tna agatha ry w ig *« jt y ; oe ee ; ty Wok seeiBiaaly 9A Maal iinet billet * gas honey Qydw gelttites cowen ua” ’ enya TO TA = te, p st ai vedak i* ane sor vee loijpontee PTS et Say y Pi Aeterna? Regal rein Jj tote banksvinw (ps8 vi Ts beotetbien Sage ~ebeoh i 8 vaae 9e digesere \ ¥ a a ve ON peters St a, yunee 4 iigewese thuw mplveos 4 wtyrowwe Shee rato . ROA woe? toe esseted bead i ‘ , TE Sigtew 2! eure Theale wed Dhacte touts ee, 4 Sea!) vote tO Bie Pol SOs TAR eO Ay i By ist "he Pe sane forte wide is i in veri Chee”; SMR use Nabeul My ind yd. Gyhedt goelvoe voah team Ba a3 0'y > 33 SE = 82 + L'0 (4oyaue [293s & J0J 33 g = G PTAFA suoyqetnozeo re, FwTS) (33 91) ,.33/sd¥y 980°0 VW ol = VF BEL = gts + (QF 91)S0°0 =H COA OR. COE ((sdtq 0z)€°0 - sd¥y 0% - Sdty SS](.95/SdFX 980°0) diy oz)(sdta cc =4 :8}~ sdyjq Aey Jeays vAoge ssew o3a13U02 Jo doy :y2249 €/T (sdty 0z)(sdty $6)9 wo = :ajaz3u0> paumsse ‘paitnbai yypta rz0ysuy Pp = a daqs ut paqe[no[ed ad10j YuUawpaquwa 4ATys (sd¥qy 0Z - Sdtyx 9°4S)3F YL i sdt 6 = (oS - oS€)uea _ Wy 9 wo TH 9°7S = 0% + 0Z A x =H Ca - aja :3uTPT[S 3S8}se1 03 parznbaa (1ajeM UT) WY48Tam JOYDUY 2 shay 1e9ys ayq Jo sdyq ye uayeq ‘JoyDUE ayy Jo oseq -8uIprqs ysutese 242 eaoge qutod uotydauU0D sUT{ BuFIooM Jo AYystay anuyxey J ainsua 03 paunsse st shay aeays yo pr33 [Iny e ‘aqdwexa i aqa Joy ‘1oysue ay Jo BurqAnd1apun quadesad pue anods SO) GO. ENR) POR Gx) POsLubes CUR Gece Ore) CLR) eck bet @anpat 03 UasoYyd aq P[NoOd UOTSUeWTp aseq IOYUe ayy JO YG ya3ueT yonm “sd}¥ 97S s} IWBFampesp Jo ays}oM paszauqne usys—aq 03 Tenba yy8ueT e yyrH Avy Teays AaqowT1ad e ‘unuwrutw e sy Aoy ieaqs sdyy 6°24 = JQ 08gd ‘aBaeq alqe,teae 343 YI}M paramo, aq Aew Joyoue ay_ ‘sqUawartnbar aseyq sqaaw shay Jeays yIFM paray}zs qeTs (341 982)(S)z = "bu z ajaizu0d y ‘“peoT [TeUOTIIIATp-TuWO 4STsaI OSTe p[Noys 1OYIUe ayy “8uz88exrp ou 1o 9[39TT Yat Aqtoedes umuyxew dopaaep 28} ‘SUOTIOIIFP OM] JO YOes uy Joyoue ayq 3ey3 saatnbar artqe[teae woo eas pazTWwTT syL adhq shay ¢ ‘sXKoy 1e9qQs [Te peqwa 03 paazynba1 ad103 [eo] *speo, 3st {dn pue [eraqe] Ystsai ysnw paqdazTes AYysyempeap sy] ayq3yenpeap (atdmexa zoo[zeas pues syyy 103 ‘uoT}9e[28 aTqrsneTd jysow ayq se suTewaar 1OYyoUE Aay ABays eq? pequa 02 papeesuU 29103 [2902 342 FO YOL ay8tampeap y -quawdrnba Buyqnozas pue Buy _TFap yo Aqr{rqge 4qnoge st Aay 1e2ys @ JO 4YStaM pasiamqns syy :330N) -[}eaeun pue ys02 ysTYy Jo asnedaq pazeuIWITe 91B8 sioysue aT *yq8uaT, auty Buzazoow y1oys ayy Aq pazeqtssadou Aqyoeded qzry{dn paatnba1 ayq aptaoid jou ptnom Asyy, “a[qeqtnsun osye aie 341 882 = sioyoue adkq 8eap quatotyya ssay “sioyoue adAj Quowpequa uot IIaT es ZI aS daap ‘quatatyya Jo asn ayy squadaid rzsXhey, quawtpas uTYyy syL aoqoue 004 = ueq (33 41) +S (3 ) 0z = b Kas ore Soh ' sz°0 74 71) 394 09 uoTssndstq/uotqzepnope) dais isy Aoy 1eaqys 2uo paqua 07 paiatnba1 as107 Aay reays 13d xqT Lg = (a3/-UE ZU/-UE Sz"0) (a3 91) (324 9zy)s0°0 = “4 uoTANTOS :A0y 1vays yoee jo 4YysTa4M “squowaoe,Td 10youe 10JF aTqe[ eae sf YIUTA ‘Suz [puey Buyanp sewep ysyser 03-0 & YIFM BB1eq yY “BuyI0OW ay Jo apts suo UO paztWIT ST Woot eag ‘AT[eSeq SATSSeM S19A09 03 43802148 Aay 1e2ays peppe apyaoid 0 pues uofso1I09 aakey pues y7q3-3003-G ayy ‘“see1Zap cE jo vTBue voyzDTAz e pue 39d Og Jo AYBTaM QTUN pa8iomqne 1OJ¥ MOTTE OF pasn 3q TT} 23BTd “UF—-y/1 Jey43 suMssy @ YIFA puss paper’ [ [am & SF AUaMTpas 10OTJZee8 aY_ “I299z OY ST YQdep 193eq “STessea [TEMS IOFZ Buyazoow yurod a[8urs @ se pasn aq 03 st a8eroyoue ayy ‘“sdty OZ JO ad103 AZtTdn ue pue sdty OZ paaynboz omayuya azetd “ut g/T JO Jd10J [1FAVT & YSPS9I 02 paus;sap aq 02 SY AOYOUe WYstTompeap Y “UOTJeWIOZUT USATH ul “UF 9IT°O = 33 L600°0 Tooyyeas pues “UStseq aysteapesq =] a[dwexg (733/44 oot) FSX 9°12 # SHATHOUd ATdWVXa 70°0 = 3 3 41) 23 /8dTy 090°0. u Z/t :Aoy Iveys JO ssauyITYL UOFIDI2ITP Yee shay Aw9Ys ¢ = G*y ul _3 91) (,33/8dF4 090°0)L ;UO}IIeIzp suo shay Fo JaqomYN :eAoy JBays [9938 pownsse yo ustseq 2 31 iat erhat-€8: SPs Filise 253528.0 = lage St — : ce peste tay 34 <5 SAE fot eats ain Bedeh os bertoy>s sore? = F Senco oo GF) «| oS ; ee : Simi dees aaaly 6 babies toecinet at iovety | 2+ 2 Send sends fe03 RePas oF Bebary Seve? 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At4A> NREL = FE eT 2 ® p 23S ene bet 5 Pevbent_ - eigees? = ae Set LS Sagi> os Ja exec tavsivi & Deter wf deegiash «4 o} eh wetoes Higleceied A _ cp jragatet eget get rsom paibet cigoit = re. teev of et a xpesntzns ofF #et8 96. 24 octet Stiles ce baz sgiy & Efile bred beteig itew_e ot ssdeiice soolkqay af fork o£} Ag a3 ts8 0 glecare i feme 29 weged base Sikp-inot-2 ad? .*vargt et 40- Sip elias? © inc toe Sh Te fp we bine bagoredtos setSf © 2tiv SgyeE,- .getrote whe Yo aha gto ao bested? 4) qian ost *isend evingee Sitero Aesneig sectet sa} obveiices af onty cise Eis Fy! > qs tt Seg erty 2 Scoesse i3ee!] Nearitae pity of Tedys26 - eIeSISG SET Seeing =e sdaIve C Sf@ativess ols ries ie oO) ot Se catieexsee 2 keg. FTE tas » seers? betesietio sos azote ir Shgiowiesh 4 FEST peEe pellwots dues gaslited tc- ell ite (Mol ipeiss oidicoaig tenes wes St anteeot. todsan qe 3 A2 e Seat lie 3 TW at bo. + = ow i eo Tass. ° a > ‘te wy heats Sti fey raat titwsts | S37 zeta Ot + exile 2211 a2 a) Tats F t ipedese ieafe-e sa} 43-6 = 2 Bisty gent ssieles iaris} If (3 1), ot) H Wa a pe8zawqns yod O¢y = Se 9 eel os JQI 000'€ ~~ IW8reMpeap WqQsTeM ~ i[@fAaqzew yYyszampeap ayy yo Ayysuag sdyy €y = (sky) dty 1, - parznbez sdty yy = ipaatnbex yd07Tq ssem aqq JO AY8tam pesiremqns FAT OLOL = (3aT 68)Zt = “M ZI = Bhoy reaqs Jo WYBTIM [oIOL sdty yy = 343}tem paaznbea ‘snqy sdty €Z = 341 007‘€% = (FAT SE6T)(9)Z "bu Z 4 isy shay esys paqwa 03 paaznbar 3q379q sdry oy = sdty oz + (Sdty 0Z)Z°t “a + Yy A 18} Butusnjreao 4sqzsa1 03 partnbar zy3TaK sKoy 1v2y48 243 paquia 02 pairfnbaa 4y8zem ayQ (7) pug ‘8uruanjisa0 quaaaid 03 paatnber 4y8tam aya (1) jo JaBxe]{ 243 St parpnbaz yy3t~am pasewqns " 341 SE6L ZS F: Gs 901) Cur 0z1) 341 68 - c} (UE OZ) ("UF SZ°0)(F84 1€°1)6 b Wt Ady 3BY3 JO AYZTaM pe8aewqns ssey Aay ze9ys auo paqua oj paigtnbaa ad107 341 68 = (3 5) 2693 01) (324 92y)1°0 = "a :Aayqy 1eays tad 3y48tam pasrewqns aqetd ‘uy-y/{ Aes “ut GZ°0 = ¥sd_ 009'1Z 9° u o ("UF ozt) (roa caa) + (8d gt'toy| “F O2t Z/t :Buypeo, [Tereqey Japun 8uzpueq ys}se1 07 shay Bays Jo ssouydTYL *[@302 ZI JO UoTZDeAtp yree uy shay ABaYys g aEH ge°9 = 1 + BES = (a3 01) (32d 92) + (7335/7 UE 71) (¥8d 91° 1)0Y LER? Gale F v7t) rsd ET) 002 sUOFJIVITpP auo uf RAY AGaYs Jo AaqumU paaznbay :sfoy IBays Jo usyseaq MO 33 OL = ‘UF OZI = A ‘az0za19y], 3at oo0'oz = ‘a < gat ooz‘zz [C484 9t°1)(Z"0) + ed Te-TI,C4F ot) = Ta red ott = (red te"r + Fed o'T) t. (les *s) 2 = os yed 16° = ("uy z1)9z0'0 + ot = “Fs ?Z 48 43300138 Aeaqs [T}OS “Uy ZI = Zz ‘UF OZL = a Ounssy +7 TeFIL *[[eus 003 3} ‘UT Z/ = g ‘ENqL sat o00‘0z = 'a >> 3at o0eL Ny [(¥8d 60°1)(z°0) + Fad BUT), uF 72) :°UE ZZ = q pewnsse 10z Aqyoedes peo, [e19,e7 rad 60°C = (48d 611 + Fsd ot) t= (ts 4 %sy Zs Ms :Z yadap Azaa0 y{8ueI19s Jeays [fos asersay red 61° = ("uy z'4)9z0°0 + ot = © 4e 3Z 38 yq3ua148 aeays [JOS ‘ut ZZ = Zz ‘Ut ZZ = @ Bunssy <1 [eTIL ( "Ss z0+” n = al s)a= 4 tAoJaa pue [ef1q Aq MoTaq uoyjenba ayq BurATos Aq poaurwaeqap ST (9ZTS) YIPTA Aoyouy “AduaTITZZ2 peoyT [eraqeT 1OYIUE azpwtxew 02 paqoatas st shay Jeaqs YyIFA AOYDUeE WYZTempeap y zn *sayouy Uy Bs} z ‘}sd uy sy 8s BIdyA zn z9700+0T= 8 [tos Aet{> 1A0¥ uoyqdzazasap aypyyord yqsuaaqs q sdiy 07 = “A ‘Te uozZy10H A ‘ sdiy 0% = J ‘T89FII19A :qy3ftaapeap 03 pay{dde sao10j3 auf], Burszocoy & uo} ssnos{q/uoy eTNITeD deas *yod gz se 3q3yem AyUN pa3rowqns 9yq pue O°Z se paqioder sy [ey1sqew 242 jo (3s), ,Aararaysuas ayL *(‘ur) AgoTJeVs MoTaq yjdep stenba z pue (fsd) yyBuer4s 1894s paufespun syenba s a12ym ‘2 970'0 + OTL = § 03 BuFpzodse yydap yyy ATAveUTT sseatDUF OF puNoy 8} qUamspes sTYqI AOJ YIBUIIAs AvaYys poutTerpun ayy “AeTS AQT FS Jo T2AeT Y¥YI-3}-G @ AOU STF [TOS ayL ‘adhq [fos 10x ydaoxa po8ueyouN sutewss [ a[duexy roy UsAS ejep [1[e aunssy ~“UdATH Yootyeos Avly “USyeeq yqepompeoq :z e[dwexg rr 32 eae _— - at w= = kt Peers a 7 —— “im < =? te meget oe af beatecws igen becteeiet Se See gpetersines snver-y 4) betaeces aneler ad7 tte “= 7 met: eth a8) Senter 43 - tare seg iee eas 153 ~ ye gttexeli re solves eS ieakeses ake at i ee = . geht ed & ghd oc 9% (ogi 2EIT.. * ee ee ee a = : awe mi4 1 = 4b its es eal fer Fai’ = ; mah) AD < fig hee Eecprees 40% ber ACM UAE CASSEL = LE © Wye sesin Mette Kewt ) ‘trilepa tel! aoe SAF te Melee Sagyeme “i te raysnt q4 i+ ihe ee PY - yhabeeine ijievtes? of) af ie Sepresivne Sao SS + ee o Jag ierbews sip ive 2 J toe ays en oe sArimeea é teh igen Pedin? sntl yoizent! = ; : : es es 2 sdbptvast Sgn PT abamaved: Lior gals 36) sebay nani ettiowe dete - EMO.e + Ee) eobsat €b ul = (ing fiat 0 erate ‘ solebse of SAYreiag gf aged stands 210 Gulres digtostert & oe] lata) sole esaock Wort hoPs-Seel jetster yotsie forse bote Debut ed veils? echesps edt gate lot zs tenieres 8G aPx= 2 as - 7 cette L9x8 ok £0" = ,.a8 St = & sureek<- 23 Taese Se tigaret ig; O80 = Link 0.91869, 0. + 9.2.5 <8 “Ss -digsh vere exyeetery vamte Flee epereva tog OF.5 & feo FFT * beg orp t= i ef ‘* ws 2 a 662° RV > @ heecven Get wSinecas Weal fesse “dideq 86. F900.03-5 Seg OFT E at 2 a $67 323,05 = 8 +2 Tdi eeet = a7 (fms oo ef 2k $4. e & . awit yeet’s. Pheg et Si Sa a & = sanaecd = felst 58 te 4igeens Fey 8.70 = (ak TPNEO.C + .F x” beg St = Chee 4 * eg B= Lt Ses : ffaeg $4, 0)ts.0F + bn dett*e. os Oe) 2-8 Rat HS, o6 wT + ¥47 OOK, cs = mt, 22. GF nd ORL GE ga0therett £€ PILE ANCHORS Operation Tring Ipe forse Definition. Pile anchors \ we achieve holding capacity by mobilizing shear strength of surrounding seafloor material. Bearing pressure and/or skin friction/adhesion are used to achieve capacity. faleral cory POCSEMTE Cost. High installation costs ship focjton usually dictate pile anchor use as last resort. Construction. Basic steel shapes usually modified to act as anchor piles. Installation. By driving, often in partially predrilled holes; in hard strata, by grouting in fully predrilled holes.’ Screw-in pile anchor (considered under plate anchors) [Refer to Chellis, 1961, Havers and Stubbs, 1971, for detailed discussions of pile systems. ] Pile Types/Methods to Improve Performance 1. Mooring Line Connection Surface attachment - Inspection and maintenance possible - Swivel/U-joint desirable to reduce connection torsion (Ref Doris, 1977). Subsurface attachment - Inspection not practical - Applicable to unidirectional loading - Enhances pile lateral load resistance; pile bending stress reduced - Changes direction of pile load; higher vertical, less lateral load. De Pile Head Burial - Places pile in deeper-stronger soil - Used for offshore moorings when drillship is available for drilling and grouting - Load at pile can be reduced significantly, by mooring line resistance (see drag anchor section) - In sand, pile anchors buried few ft to allow for scour. 3. Near Surface Fins/Collars - Used to limit pilehead deflection/bending moment 33 foods stand “oe of hott thom ar mi ;eeled bal Livherg. yileiveag os astie ,gaivich ‘a te ta velig si~wors? ',aslod boliizboag elie} at gattuesg yd x2 (2900 (etifedd o2 ve%K) Covddons sdelq rabay bazobtagng} ‘ee | f.emeteye slig to saninsuserd baligteb rot ,TTOr ,addnse tae si r seittinautach evoxgml ot sbouldst\eaget mottseann) said hue * aldisacy oopAscsiatan baw mottoeqeal-~ tanmdosd je soetautl Sauber of sidexteah dntopel ieviwe > Rs ah sAVIOGL ,ePsotl oH) aglaged aokissuad — oe {askiosxq Jom wokdpsqant - caseddosje sostaeee Oo gaibact Leiotiossibiau of efdeakiaqgA - sannatatees beol Isvetal ofby agomailod baciihos omexte gatheed olig tefigid jbeol slty to notsseteh esgaad) - Dhol iazate? wsel, pfadbisiav fetzull basil CVE 3: cae Lion tagnowse-xeqesb as eheg eeaelt - to% sideltews 2: giuaf lic gadW ageitoom sxotegag ten baal = ; ghisvoug hoe gakliieh = anil guizooa vd), ylonas i¥ korg de basubsx od neo SISSY te Died & (noksage sodoua garb e6e) -eoapserias tho9a 26% wolls o} 22 Wek Gelund erodons elie Gees aI + wisliod\aakt aaadaut Retest joomem gnkinisd \pottositeh baotalig simit oa bout =, 7 4. Built-up Sections - Fabricated to produce section modulus to resist high bending forces/limit bending - Sections symmetrical or asymmetrical depending on loading directions. Variations of the Basic Pile Anchor (4) (e) ca (Sw Vis pile. A fay qlochrsen? decreases or onmn- directional wide flange. bendin mogay a pie Cis 3 for en yey 7 (e) ES Siero! corty (res$ure. geng 09 chow 7 cf C Me ae ee, how pile beed driven below ts Is at pile ead Sieben 7 pomT seofloor jp decrease 1b mereose lateral en! per bending momen? 7 pile beoring TED C. Installation (Refer to Chellis, 1961, 1962, and 1979; Compton, 1977) 1. Driving - Most piles in soil/soft rock installed by driving - Many hammer types easily modified for use to 80 ft - Pile hammers developed for underwater operation by Raymond (1979), and Hydroblock (1979), (Hydroblock to 1,600 ft) - Can use follower in shallow water - Deep water - refer to Anon 1979 for discussion of a self stabilizing "puppet" system for pile installation. De Drivability - Best method for evaluation of pile drivability/hammer effi- ciency is the wave equation. Refer to Smith (1962). 34 ’ € by, < ae on Spa Pes SE Vis SHG t ‘ ; ‘hs Seo ae ee yen ETTOL jmotgmod ;OTeL has , SORE, fee! ,atllodd of aeteh? nolgel ts geivind gnrvisd vd palletes? 407 Troa\ftoa ak eattg 2aoh = #t' 08 a3 seu 40% baktibom yiieas sadye seamed er “ bdoayed vd nottstoqo wedewrabhy 10! beqoleehh asameed ald (33 GO3), { o4 W706i desbyH) pLave 2) i320 Ldox Sah ee ARTEL) tedgw wolleda ot tewolhot Sau os) =~ 7 t{sa-s Yo ookleauseth sok Otel sonA od iahea.= tadaw qeatl <* molieklajent ofig god astay: “Ieqqua gaisiiideta 7) ytiedevi a “E3t9 ssomnd\ysilidarksb otq 26 soisauieve 10% hoddun sasd - (Saul) detad of sete i teliaupe svew saa af Yocets ee 3c Drilling and Grouting - Used when predicted driving resistance exceeds hammer capacity - Typicaliy used in hard coral, rock - Recommended for use in calcareous sands and soft silt where developed frictional capacities are low. Pile Installation Methods ~ pile y groul (@) Driving (b) Drilling and groiling File. mstollatoq meftods. - Grouted piles can be underreamed to greatly increase vertical capacity. - Underreams of more than 5m dia have been con- structed @ 40m depth in the North Sea. D. Pile Capacity he Lateral and uplift force at the anchor - Forces on buried pile are altered in magnitude and direction. a. Simplified Analysis - Assumes no friction along buried (4) Debaitiog of Terms chain 35 ae Isamnad abaaines soneietes? + gnvwtol ieee dads, , fexos bred ot . ree sredyv ifta mine bow sheds Rimereolao a oe wel, age aolst Flared ” ee wees Ser ae Sa ol i a arg 6 \ ~ re Ne ‘, - a A i aa oe 2 wee * re oy _ -_ euaiis Sl 4 “RAG Soh, 7 zara Ye eA LD) a 89 asthe yizeoty oF basses isoiataw 4 add 330m to aeaTt aa ~u02 nsed evad ID) at zyab Od 2 ba tinatt Boe nao 3 1 Jit Eom ro ‘tasoad nods waka: 3a exo) ’ hak eud ao. ager buretia wae fig baa shysibase mis igghtosa Ib bertetenit’ akeyland on eng | - podto ts} behing goole - Results in over estimation of F_ and under estimation Vv of F, by up to 25%. h Sand F = Zz = N cb c a Yp q Soil Friction qd = characteristic chain a or wire diameter (for Angle N chain use 3 x chain size) q 20 3 Clay 25 5 30 8 F = lls z 35 12 cb u qd, c 40 22 sy = soil undrained shear strength Force components at the anchor given by: DW, 2 1 OF c h h b Fe = Bes Fi b. Refined Analysis - Refer to Reese 1973 and Gault and Cox 1974. 2. Lateral Pile Capacity - Depends on soil strength, stiffness, load type, pile dimensions and stiffness - Rigid and long (semi-rigid) pile analyses are possible Rigid Pile Analysis. Assumes soil failure occurs as an infinitely rigid pile rotates about a point on its length. Procedure is very conservative; results in pile with minimum deflec- tion at head; can be used for preliminary pile selection for long pile analysis, (Refer to Czerniak 1957). Long Pile Analysis - Many procedures available (Refer to Gill 1970, Matlock 1970, Reese 1974, Broms 1964) - Procedures are labor intensive; generally have been computerized - Procedures rely on a pile/soil interaction analysis where pile/ soil deflection characteristics are needed - Procedures rely on establishment of load-deflection (P-Y) curves for soil, typically based on test experience. Sr Pile Axial Capacity Capacity treated as function of shear along the pile/soil inter- ‘face. Both cohesive and cohesionless soils can be treated as frictional materials. 36 nokialed £168 Le of ere e oe 2 és 8 OE st #e gs be tyd gewty rodons ait 3s a ekagianA banttelt i a sAT2F x02 si 40gd9 Doe eter auced of sete bit ! ¢tivagad ‘otis hahaa eltq ,sqy? beol ieaieese itque132@ Thee ao shasqed > asonktiza bas ante eldiesog sie eseylane slig (bigtx-imaa) ysot Size ee vegintiol Re se axu720 sxeizet [foe anmpaah Shans aA at Ln eS -dsgnal @93 ao tokoq # suoda: a4 Jou oli “oolieb sumiotm diiv sliq nt @tigesx jevidavrsenas 2075 gool xot metioelea oliq ytkabmefsrq 10% bean’ od one Prabrr ys nok CVSRE dslerond of metem} iris ane al Wed windnt LOTR! Hoolss lover L620 04 aud oideliava sosahaanes ‘Ynet - (A9OL amork ,AVOL sae4it bestisieqmos nesd evad yilsxsa9g yevdeootat sodal axe eibibeoest - \eiiq stedw ateylaus noltoszot@— Dioa\slia « ad yisat eaxubeoost = babaed are #akselrstoexeds.gokjaeigad [tow a (Y-Y) noksoslieb-beol to soamdetidetas no Wise waxubsoosd - eel sonstregxs ta93 oo besid yllssiqyt ,ikoe aot asvxas |)! Winged TaixA 212%), *uajok Lioa\eliq siz gnole yaede Yo poktoan? ac bedanxd ysinagad ih 28 bojasi7 od ono alion aealagtesion bas sykasiéa Atod .opakr! . hatin pt : to if a a. Cohesive Soil Refer to semi- empirical method of Vijayvergiya and Focht (1972). Pile frictional AS (a Fe VA resistance (R_) expressed as function of mean undrained shear strength (s_) and mean eftective over- burden stress (o_) over pile length. Pile Fenetraliog (CH R, = A(o + 2s JA, A = empirical coefficient (below); A = lateral area of en- bedded pile (use area of Frichoqal cepecity coehbreed7, a ) enclosed rec- versus pile penelralion tangle for (Aer Vijaywergiya end Foctl, 1972), "H" pile in clay. A Method Simplification - Above equation is rearranged to simplify process. R/AS = fn = average, pile side friction - Iterative selection process required; Determine axial capacity then increase length if needed. 37 (4) NE EL ! ohn as & sik = saskotttec2 A a(wolsd) a r peeetat = Fi er —o ko wezh - alhy Babbed ch Mendes earn Wwepeiipee to seve een) : wiletagen, has a ie “Ie bsaeclony RRR The eve eefinsansghS whe) ‘307 Sigany a at afig week, eo ED eo ETE iqute bodaunt & ; gr Fopkstgns. = a ot 7 gA\,f .s2e007¢ YREigabe oF bogontseo% et aottaupa veda” « motkioiny, shia, ahh reer faixe acnkereiod jbexbugos eses0%q nobss ce bobesa “9h Gigaset a ee 2a ee S ’ . Sim = 16.0 pSe EN a S st ~ 9 aS “v SL SE o . wy EN iS Ss) v X x 80 30 ¢ £0 2.0 72 29 ; al 08 70 r-) 4) Z) 200 Yoo wr) £00 1000 1200 Crepes. ° 7) 2 so ¥o Ey) ) 7 fe Yo 700 Pile entedded /erg%t, Lp GD) Fiverege agit side poelen, kh 5 "4 cogeswe. Soul b. Cohesionless Soil Unit skin friction fy at any depth is f = Ko tan 6 Assume K (coefficient of lateral earth pressure) = 0.5 o = effective overburden pressure 6 = angle of friction between pile and soil (assume 6 = @ -5°) - Pile capacity R, = f A, - Average skin friction has been found to peak at pile embedment ~ 20 diameter. - Recommended value ef £, for long piles compiled from Ehlers (1977), Angemeer (1975). 38 te iw ‘Cro@ easlnolawied | ve) ls = : : Pa ra An Omas oN = 7 ab Staab Yow 46 2 wotsots? give Jind -0 @ (etugaerq dirs Tease Yo S50 tX3509) .X Aas srivesig mebrgdssva aviisstte = oO thow bas oli seaweed salitiiad Yo aligns = §. (72 4 = & sewage) At 2 yaioages WLEF 4 snombodas oliq 30 dandq 09 beet need zed polaode® Giles egei808 ae getter OS os Gi) sxslags mort balboa asif¢ snot 10l) 2 Io setae Sabremso2 af! (8¥Of) xeamegad Recommended Skin Friction Values for Sand ; 6 : imax | Soil Installation idee) leds eae | | | | Sand driven or drilled and grouted o-5 0-5 13-9 96 Silty sand driven or drilled and grouted | g-5 16.5 | Roe | 81 Sandy silt driven or drilled and grouted | 0-5 10.5 9.7 | 67 Silt driven or drilled and grouted | 0-5 |0.5 | 6.9 | us Calcareous sand drilled and grouted o | 0.5 | driven (0) }0.5 *Depends on installation technique; may be as low as 3 kPa (0.5 psi). Anchor Pile Loading Effects of combined axial and lateral loading are poorly understood, currently treated separately. Repetitive loading can cause large increase in lateral pile deflec- tion. Methods to dampen/avoid repetitive loading should be consid- ered for piles in loose sand/soft silt seafloors. Chellis (1969), suggests "a rough assumption" coefficient of horizontal subgrade reaction for soils of high relative density might be reduced by 1/2, for soils of low relative density - reduced to 1/4 initial value (data provided for plate anchors may be useful as a guide in evaluating effects of repetitive loading). Effects of repetitive loading on vertical piles are speculative, (research projects underway in United Kingdom and Norway). 39 ; Werwoag Miby, Oat fink’ 44 asétaht } i é-$ | Beseang han Sal ah Ve wevirh ta . ely g) 24 t Sosuayg bee SeeSEth 9a auedah 7 oe | B.a) 7 dod], te tesa fina bebhiay 59) oe i Zt i He Hel m4 | bescagg New ba llrsd Fe Direc, eel te i pth (ban 8.0) ety Cas wal ae si tae jmwphmdons ao surlaoiid ay = set i saibeot sts phoospzaban, Vixoog 3x8 stheal, es ‘pte eine bouaaea te | Yistexeqes badesi3 eh nooftsh ofiq Isretsl ni sasersat agual aie neo guibeol ovises =hisaoo 9d bluode goibapl avitizaysy beove\arqneh of bodied. vatoolisss tffe Stee bane sacol uh ealig’ 738 %o tnsinittsos Nnotiqneets Uguox «” etaeggue , (Qd@5) abl ysieneb-svisaloy dgid to 2lkog ga} woisosox abaigdus Lage ~ Yireneb svisefsx wolf to efkoe ro ,S\t vd bssvbey ed ezodoan a76fq sat bsbivorg s2pb) éofev fetainr Xf ot ba . SVitissqs2 So Satis anlivewievs ok sbigg 8 28 Lviesy ad pov -Canibecd | sovizaluooqs ssa aeliq Ieattzsy no antbeel sviiiiegey ia) ‘aso (YewroH bas mpbgibil patgnl nt yawsebau stoeforg wanes RE ACKNOWLEDGMENTS Published and unpublished NCEL reports on anchors and soils provide the basis for this summary report. The contributions of Phil Valent, Mike Atturio, Rick Beard, and Homa Lee of the Foundation Engineering Division at NCEL are acknowledged. 40 sbivoud alioeg bie dicdons ao qdou04 1200 't 2g ,inetaY L2d4 16 anotteditgaes AT yl r08 “golvesatgnl fot tabaust wt io sel smol ; eis 3 area Oa REFERENCES Angemeer, J. et al. (1975). "Pile load tests in calcareous soils con- ducted in 400 feet of water from a semi-submersible exploration rig," in 1975 Offshore Technology Preprints, Houston, Tex., May 1975, p. 664. Anon (1979). "Unsupported underwater pile driving: The soil-independent system," Petroleum Engineer International, Mar 1979, pp 10-15. Beard, R. M. (1980). Holding capacity of plate anchors, Civil Engineering Laboratory, Technical Report R-882. Port Hueneme, Calif., Oct 1980. Broms, B. B. (1964). "Lateral resistance of piles in cohesionless soils," Proceedings ASCE I, Soil Mechanics and Foundation Engineering, vol 90, SM3, 1964. Chellis, R. D. (1961). Pile foundations. New York, N.Y., McGraw-Hill Book Company, Inc., 1961. Chellis, R. D. (1962). "Chapter 7. Pile foundations," in Foundation Engineering, G. A. Leonards, editor. New York, N.Y., McGraw-Hill Book Company, Inc., 1962, pp 633-768. Chellis, R. D. (1979). Handbook of ocean and underwater engineering. New York, N.Y., McGraw-Hill Book Company, Inc., 1969, pp 8-56 to 8-98. Cole, M. W., and R. W. Beck (1969). "Small anchor tests to predict full scale holding power," Society of Petroleum Engineers, SPE 2637, 1969. Compton, G. R., Jr. (1977). "Selecting pile installation equipment," paper presented at the Associated Pile and Fitting Corp. Piletalk Seminar, San Francisco, Calif., 1977, 13 p. Czerniak, E. (1957). "Resistance to overturning of single, short piles," Journal of the Structural Division, ASCE, vol 83, no. ST2, Mar 1957, pp 1-25. Douglas, B. J. (1978). Effects of rapid loading rates on the holding capacity of direct embedment anchors, Civil Engineering Laboratory, PO No. M-R450. Port Hueneme, Calif., Oct 1978. Ehlers, C. J., and E. J. Ulrich, Jr. (1977). "Design criteria for grouted piles in sand," in 1977 Offshore Technology Conference Preprints, Houston, Tex., May 1977, p. 480. Foss, I., R. Dahlberg, and T. Kvalstad (1978). "Design of foundations of gravity structures against failure in cyclic loading," 10th Annual Offshore Technology Conference, Houston, Tex., May 8-11, 1978. (Paper No. OTC 3114) 41 30 oT (exer galt per tos egoH prep tee jasbesgsbar- Ttoe od? :guiviab alin 2odaws obaw boo q ref-OL qq QVRE eam fasodseeeaal ts9n0k: golrsenigna fete ,azotoas.. ajaig re efioaden Pete) Bel 290 RELeD ,*msiswl trot .f382- a axOGaR 13) au zesinoissdos oi aslig to apeedoLaur terstet” (uaeey sgurzssalged aoktebavo’ brs a2tandonl hi0k FE sce agakt Li si-waxdot ,..¥.M da0¥ wel ey obi nokisbasot ai "short abavo? siya, 7 saved” dood Lfit-wardoM ,.¥.0 ,dvoY well, .wosthe , abdeabal JA. 8 ’ re BNt-6e8 a « S08. eu mt ig i ae i" : . -gnizsnaigna xssawrsbay bas asase tn dooddnAll fever) a . -8Q-8 oF S¢~8 qq ,C30l ,.o0% \ynaqmed soot iLiit-wesdotf it ti ¥ {fut ssibexq ot. etess sodone Liaw" (ener) daat .W 8 bate ee Vee , TESS We petodai god muslegset Yo yreiooe ", towog sania ", snsaqtups dokSeiletent afkq gabroas ag" ACSRRL). xk lk. * vi -teal@ad Aletatis i Sne3tii bos, Sitt bosaeaaged add te hia 4 | 9 Gt ,TVOl” 2htad) 90Bk: "justtg d2eda ,slgats to gatoradueye as wonetaresn", (Veer 4 x an /VEOL zat £72 .o0 ,€8 fow 9024 ,nolaivill {erudooese alt Yo Tag gothiod pdt ac yates gobbsol biuea 36 etvettX | AATOL) aa ‘a « lg OF ,~vtessiodsl sqirsenten® Lived i avoieas tnambadms “sastih to tear »BVOE 390 tried ,sneneue add it 302 sits2i29 ‘og leat! CVVOE> veh .dokaty a i bak , a : ,-S3atiqetd s2ansistis) ygofoa isan sradetio VTer at " bikes ot sti rv. O86 sa eA SOE yon «Rady anossabauo’s to ageeot’ (Over) Sasaleved .T bas asad ined ee founds Perr (S000! aifoyo af weulrel tantags aetotouste yak toon) BY 2] Tt-8 “ell ,.xaT ,Rodadol , sorsyvataed yaolontosT AALKE OF Lye Gault, J. A., and W. R. Cox (1974). "Method for predicting geometry and load distribution in an anchor chain from a single point mooring buoy to a buried anchorage," in Preprints, Sixth Annual Offshore Technology Conference, Houston, Tex., pp 309-318. Gill, H. L., and K. R. Demars (1970). Displacement of laterally loaded structures in nonlinearly responsive soil, Naval Civil Engineering Laboratory, Technical Report R-670. Port Hueneme, Calif., Apr 1970. Havers, J. A., and F. W. Stubbs, Jr. (1971). Handbook of heavy con- struction. New York, N.Y., McGraw-Hill Book Company, Inc., 1971, pp 27-1 to 27-50. Herrmann, H. G. (1980). Design procedures for embedment anchors subjected to dynamic loading conditions, Civil Engineering Laboratory, Technical Report R-___. Port Hueneme, Calif. (to be published) Hydroblok (1979). Brochure, Hydroblok Technical Data, Hollandsche Beton Maatschappij bv, P. O. Box 82, 2280 AB Rijswijk, The Netherlands, Apr 79/5000. Kulhawy, R. H., D. A. Sangrey, and S. P. Clemence (1978). Direct embed- ment anchors on sloping seafloors state-of-the-art, Civil Engineering Laboratory, PO No. M-R510. Port Hueneme, Calif., Oct 1978. Leahy, W. H., and I. M. Farrin (1935). ‘Determining anchor holding power from model tests," SNAME (London), vol 43, 1935. Lee, H. J., and J. E. Clausner (1979). Seafloor soil sampling and geotechnical parameter determination - Handbook, Civil Engineering Laboratory, Technical Report R-873. Port Hueneme, Calif., Aug 1979. Matlock, H. (1970). "Correlations for design of laterally loaded piles in soft clay," Preprint, Offshore Technology Conference, Houston, Tex., 1970. (OTC paper 1204, vol I, pp 544-595) Neely, W. J. (1973). "Failure loads of vertical anchor plates in sand," Journal of the Soil Mechanics and Foundations Division, SM9, Sep 1973, pp 669-685. Ogg, R. D. (1969). Handbook of ocean and underwater engineering. New York, N.Y., McGraw-Hill Book Company, Inc., 1969, pp 4-70 to 4-74. Raymond (1979). Brochure, "Two new underwater piledriving hammers," Raymond International, Inc., Houston, Tex., 1979. Reese, L. C., W. R. Cox, and B. R. Grubbs (1974). "Analysis of laterally loaded piles in sand," Preprint, Offshore Technology Conference, Houston, Tex., 1974. (OTC paper 2030, pp 743-483) Reese, L. C. (1973). "A design method for an anchor pile in a mooring system," in 1973 Offshore Technology Conference Preprints, Houston, Tex., May 1973. 42 bad Yrtedosy gatinrherg yo} bad2ot" ad Oo youd gnizcos Jikoq signia’ as mov alads VaolondosT as 0Fies SY feunind: las ‘ ma, ee bobsol cifazetal Yo sieanuaenin = , toreny, eile i golrescigpd Iivid fave iret svanaogaay yin OVED agh, Witad «sient 39609, ON8-H i eit. “nod ere Rea doodbowH REROL) axt added? Ww U1 i-GS qq ,1V@i sont Dt ‘deem + ln re ea bodse—due erdifone eskieaies 403 eis wie na tot colar} favintaat wrotasodal gninasalgad Livrd (acolt thao © (berlatidug sd on). VBE TRS 1 , Aotod wMsvbaaliol jntad teotadost doddorbyt -senudlone + {Qt 1A sbaslisdson oat Mb eval ad uA vc ,88, xem 0 ark ~badus. toorx7tl (avery euiganee 18 be .vergned 7 7 c. a puirsssignd Livid: .Jis-odi-fo-esere S105 team Sal bees 1.4 bas ywadot sO, «eh >. Erie... speask 3209 peli ve, ghivesatgad iyi} nadia “a Be | ogeitl as2 ¢4 avivans, see sedans. Legobtaavned, » ‘deaueny: a ae: ‘ sf62i-W g20K Ieotidoal ,yrodapotad eaaoarged fiveo ,baefal nak O80rT Tut, ; keted ¢ aurea 3 oldsliave qilstoxvsemas. 402 wenminie oteb : tant CagRer) \smonsuh 3347 wo wrotsioded aodyponigal fivid .avedoas scoakbue § YO Fey TALIITIO Hot ~ 08ers kd ee fiwtd .ceud 26 etfusex ta5d vodpng Barotsaavas) (R080) 0 ae « ply this? ,saensull tral LSet HR 6s0n {ertadoat iWrOFer Oded a True, D. G. (1975). Penetration of projectiles into seafloor soils, Civil Engineering Laboratory, Technical Report R-822. Port Hueneme, Calif., May 1975. Valente Ps JeoeRandlayLorn He Lee. sandoR. Dey Rasle (1976) -emstate— of-the-art in high capacity, deep water anchor systems, Civil Engineering Laboratory, Technical Memorandum M-42-76-1. Port Hueneme, Calif., Jun 1976. Valent, P. J., R. J. Taylor, J. M. Atturio, and R. M. Beard (1979a). "Single anchor holding capacities for ocean thermal energy conversion (OTEC) in typical deep sea sediments," Ocean Engineering, vol 6, nos. 1/2, 1979. Valent, P. J. (1979b). Coefficients of friction between calcareous sands and some building materials, and their significance, Civil Engineering Laboratory, Technical Note N-1542. Port Hueneme, Calif., Jan 1979. Vesic, A. S. (1969). "Breakout resistance of objects embedded in ocean bottom," in Proceedings of Civil Engineering in the Oceans II, Miami Beach, Fla., American Society of Civil Engineers, 1969, pp 137-165. Vijayvergiya, V. N. and J. A. Focht, Jr. (1972). "A new way to predict the capacity of piles in clay," in 1972 Offshore Technology Conference Preprints, Houston, Tex., 1972, vol 2, pp 865-874. Wilson, B. W. (1969). Earthquake occurrence and effects in ocean areas, Naval Civil Engineering Laboratory, Contract Report CR 69.027. Port Hueneme, Calif., Feb 1969. 44 /atioe socMIaee oINe Kal tyoatore) as Sosa snengen 37 Claes: se Oa4M- Task asda “trosededel x ca? ee Ait baw, stot ESM « > bey aes | 4 ny. ret) $HS steve SOfons hgh i wir + Tigegeo) ist 7 triad , omnes steT ge mothers omnes, fa wow s70I32 (oO, GL} Dem wil (e@lel) Bead 1M U-bee joirustA (a nokia | By ht moreySvuo2 73 zone (eee .cos36 Ags bolyioaged pats : »w li .262°,.9 Lov ,garisamiong naes0 "lads sm iber- SSE be f& aos tsslao apeving HoLsioist to vinstokeeaoen “gen gutysatigad (tvid, ~pwanesttinghé sisd? hoe [abeiresaee lenineh : GVer ost | Rtiad -emrauk gro. , Shetow oton ‘a nessa he HDaepbsadmw L946 reo > S962 02 129% tuodeo2d* tg baisiM 1) auasc oft me gosrsenigad Loyd 20 mame (GGL-TEL gq , Qe -eesadtant Livi> to Yiskood' aeaay Dsbayg oo) yaw wad A’ fa shen yi Todo) 2A Uae a “a ata tna) Yar! mide tT 4:4 ist20 SUen az) (vary a pabig toy ; pig-2ag qq ',S fow Sheba + than 2AS9 25. GS5de re BIIBSZI9 Dae SoRSsesH 709 ov anpaoxiel Tod TOE a "WD: orrest w3etsn me] vod eroded oo Lyte ; f de®