THE EFFECT OF VARYING THE PARAMETERS OF VANE SHEAR TESTS ON MARINE SEDIMENTS by James Charles Singler / United States Navat Postgraduate School THESIS THE EFFECT OF VARYING THE PARAMETERS OF VANE SHEAR TESTS ON MARINE SEDIMENTS James Charles Singler Thesis Advisor: R. J. Smith March 1971 kppnjovzd ^oh. pubtic nzi&a&e.; dibtnA.baticn ujitunctzd. T 133625 V The Effect of Varying the Parameters of Vane Shear Tests on Marine Sediments by James Charles Singler Lieutenant, United States Navy B.S., United States Naval Academy, 1963 Submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE IN OCEANOGRAPHY from the NAVAL POSTGRADUATE SCHOOL March 1971 ABSTRACT The consequences resulting from varying the parameters of the vane shear test (used to determine the shear strength of marine sed- iments) were investigated. Experiment showed that larger ratios of container diameter to vane diameter yield more accurate shear strengths It ■was also shown that the four-bladed vane produced the best results. Finally, rates of rotation of one and two revolutions per hour were found to give accurate values of shear strength, while higher rates of rotation proved to be unsatisfactory. TABLE OF CONTENTS I. INTRODUCTION _ 9 II. DESCRIPTION OF EQUIPMENT 12 A. GENERAL DESCRIPTION 12 B. COMPONENTS 13 1. Torque Transducer- 13 2. Power Supply and Conditioning Unit 13 3. Motor and Motor Mount 15 4. Vanes 16 5. Sample Containers 16 in. TESTING PROCEDURES 20 A. TEST MATERIALS 20 B. PACKING THE CONTAINERS 21 C. TEST PHASES 22 1. Phase One 22 2. Phase Two 22 3. Phase Three 23 IV. RESULTS OF TESTS 24 A. COMPUTATION OF SHEAR STRENGTH 24 B. RESULTS 33 1. Phase One 33 2. Phase Two 33 3. Phase Three 51 3 V. DISCUSSION OF RESULTS _ 57 A. SIZE OF SAMPLE CONTAINER------ 57 B. NUMBER OF BLADES 58 C. MOTOR SPEED 59 VI. CONCLUSIONS 60 APPENDIX A Results of Tests 63 BIBLIOGRAPHY 70 INITIAL DISTRIBUTION LIST 71 FORM DD 1473 72 LIST OF TABLES Table Page I Summary of Results of Phase One Tests Using Grease 26 II Summary of Results of Phase One Tests Using Clay 28 III Summary of Results of Phase Two Tests Using Grease 29 IV Summary of Results of Phase Two Tests Using Clay 30 V Summary of Results of Phase Three Tests Using Grease 31 VI Summary of Results of Phase Three Tests Using Clay 32 Page 14 14 17 17 18 18 LIST OF FIGURES Figure 1 NPS Vane Shear Apparatus with x-y Plotter 2 Five Revolutions Per Hour Motor and Motor Mount 3 Vanes with from Two to Eight Blades Used for Testing 4 Containers 1 through 7 Used for Testing 5 Containers A through G Used for Testing 6 Tamps for Containers 1 through 7 and A through G 7 Shear Strength versus Container Diameter, Runs 56-62, Grease 34 8 Shear Strength versus Container Diameter, Runs 63-69, Grease 35 9 Shear Strength versus Container Diameter, Runs 70-76, Grease 36 10 Shear Strength versus Container Diameter, Runs 77-83, Grease 37 11 Shear Strength versus Container Diameter, Runs 84-90, Grease 38 12 Shear Strength versus Container Diameter, Runs 91-97, Grease 39 13 Shear Strength versus Container Diameter, Runs 98-104, Grease 40 14 Shear Strength versus Container Diameter, Runs 170-173, Clay 41 15 Shear Strength versus Container Diameter, Runs 180-185, Clay 42 16 Shear Strength versus Container Diameter, Runs 217-222, Clay 43 17 Shear Strength versus Number of Blades, Runs 105-111, Grease 44 18 Shear Strength versus Number of Blades, Runs 112.118, Grease 45 19 Shear Strength versus Number of Blades, Runs 119-125, Grease 46 20 Shear Strength versus Number of Blades, Runs 126-132, Grease 47 21 Shear Strength versus Number of Blades, Runs 156-160, Grease 48 22 Shear Strength versus Number of Blades, Runs 189-195, Clay 49 23 Shear Strength versus Number of Blades, Runs 203-209, Clay 50 24 Shear Strength versus Motor Speed, Runs 133-138, Grease 5 2 25 Shear Strength versus Motor Speed, Runs 144-149, Grease 53 26 Shear Strength versus Motor Speed, Runs 174-179, Grease 54 27 Shear Strength versus Motor Speed, Runs 196-201, Clay 55 28 Shear Strength versus Motor Speed, Runs 211-216 Clay 56 ACKNOWLEDGEMENT The author wishes to thank Dr. R. J. Smith, Department of Oceanography, Naval Postgraduate School, for his assistance and continued encouragement throughout the planning, testing and evaluation periods of this thesis. I. INTRODUCTION In recent years there has been an increase of interest by private industry and government agencies in determining the physical prop- erties of the sediments of the ocean floor. The shear strength of marine sediments can be measured by un- confined compression, direct shear, triaxial shear, and by vane shear tests. The first three of these tests usually require the removal of the sediment samples from a core liner, and may even require the placing of the sample into a special container for testing. This hand- ling produces further disturbance to the sediment in addition to that -which may already have been caused by the coring process. A vane shear test circumvents these problems as the shear strength measurement can be performed in the core liner or even in-situ [Smith, 1962]. Many variations in vane shear testing equip- ments exist, but all are based on the vane borer as developed in Sweden and Germany in 1928 and 1929 [Osterberg, 1957]. Cadling and Odenstad [1950] earlier reported on the use of a vane device for measuring the shear strength of terrestial clays. The device made use of a vane consisting of four rectangular blades and a calibrated spring to measure the maximum torque developed when the vane was turned in the clay. Once the maximum torque was determined the equation of Cadling and Odenstad was used to calculate the shear strength: M g = max [TTDHD 2 rr d2 1 D\ I 2 4 3 2/ where M = maximum torsional moment required to produce max n r shear, D = diameter of the vane, H = height of the vane. The above equation assumes that the surface of the rupture con- sists of a circular cylinder with the same dimensions as the vane. Additionally, it is assumed that the stress distribution at the maximum torsional moment is uniform across the surface of the cylinder, in- cluding the ends. The rate of rotation of the vane was reported by Cadling and Odenstad to have some effect on the shear strength values. Higher rates of rotation produced correspondingly higher shear strengths. A rotation rate of 0. 1 degree per second (6 degrees per minute or 1 revolution per hour) was arbitrarily adopted as a standard, and this rate gave conservative results. A rate of 0.2 degree per second (two revolutions per hour) was used by Morelock [1967] based on the assump- tion that the value of shear strength obtained was very nearly the same as at the slower rate. Aas [1965] reports finding no significant changes in shear strength at rates ranging from 1 to 10 revolutions per hour. A height to diameter ratio (H/D) of two was used by Cadling and Odenstad [1950]. Aas [1965] experimented with various H/D ratios 10 and concluded that results of the shear strength determinations were not greatly affected unless the H/D ratio exceeded a value of three. Osterberg [1957] suggested that the area of the vane should not be greater than ten per cent of the area of the sample to be tested. Because of the many differences in the parameters of the vane shear test, further study into the effects of varying the parameters was thought to be necessary. The parameters chosen to be varied were the diameter of the container, the number of blades of the vane and the rate of rotation of the vane. The parameters of vane dimensions, H/D ratio, and container height were not varied. A study of the effect of varying the parameters would permit the evaluation of previous recommendations, the standardization of vane shear test procedures, and valid comparisons of results from different test facilities. 11 i II. DESCRIPTION OF EQUIPMENT The basic equipment used for testing was chosen because of its availability., versatility, and suitability for the tests which were per- formed. To vary the parameters, containers of different diameters, vanes with different numbered blades, and motors with different speeds of rotation were required. A. GENERAL DESCRIPTION Commercially available vane shear test devices have been made to specifications of various testing facilities. The Naval Postgraduate School (NPS) vane shear apparatus was used for all testing as it is the best equipment currently available in view of its adaptability to this investigation [Minugh, 1970]. The NPS vane shear apparatus consists of the following major components: 1. torque transducer, 2. power supply and signal. conditioning unit, 3. motor and motor mount. As originally constructed by Minugh and subsequently modified by Heck [1970], it utilizes the above components in conjunction with a stand and a height adjustment mechanism to lower and raise the vane into and out of the sample. The heavier laboratory stand as described by Minugh was used along with the height adjustment mechanism 12 developed by Heck for this testing program. Holes were tapped in the base of the stand to hold the various sizes of sample containers. The complete test apparatus is shown in Figure 1. A strip recorder and an x-y plotter were used to record various portions of the results of the tests. B. COMPONENTS 1. Torque Transducer The torque transducer selected by Minugh has a range of 0-250 inch-ounces and may be over-torqued 100 per cent without damage. It is relatively insensitive to temperature change and measures either clockwise or counterclockwise torque. The use of semiconductors enhances signal discrimination at low output levels, making the torque transducer more effective than conventional strain gages. 2. Power Supply and Signal Conditioner A combined transistorized power supply, bridge circuit, and amplifier provides a signal which is sent to the recorder. The unit is provided with a push button resistive circuit equivalent to a 125 inch- ounce torque and may be used to adjust the amplifier gain. By depressing the "R Cal" button on the unit a fixed signal of 125 inch- ounces is provided to the recorder. The gain of the amplifier is adjusted to a convenient reference (0. 5 volts was used for all testing) and by adjusting the amplifier balance the full 0-0.5 volts travel of the recording pen is ensured. 13 Figure 1. NPS Vane Shear Apparatus with x-y Plotter Figure 2. Five Revolutions Per Hour Motor and Motor Mount 14 3. Motor and Motor Mount In addition to the motor and motor mount as devised by Minugh (one revolution per hour), five additional motors and one addi- tional motor mount were obtained. The five motors were chosen to give higher rates of rotation of the vane. The speed of two revolutions per hour was chosen to verify Morelock's [1967] assumption that doub- ling the speed of rotation does not result in an erroneous value of shear strength. The values of five, ten, twenty, and thirty revolutions per hour were chosen as convenient multiples of the standard speed of one revolution per hour. Four of the additional motors were used in the existing motor mount and a second motor mount was constructed for the fifth, somewhat differently configured, motor (Figure 2). All six motors developed 150 inch-ounces of torque at 1 RPM and required 115 VAC, 60 cycle power. Five of the motors rotated in a counter- clockwise direction while the sixth was reversible, but was only configured to rotate counterclockwise. The speeds of the motors used were: - Degrees per minute RPM RPH 6 1/60 1 • 12 1/30 2 30 1/12 5 60 1/6 10 120 1/3 20 180 1/2 30 15 For ease of reference all results are compared on the basis of revolu- tions per hour (RPH). 4. Vanes A total of seven vanes, with from two to eight blades, were used. Standard vanes have four blades and varying H/D ratios. The range of two through eight blades allowed comparison of results with both fewer and greater number of blades than standard. A one-bladed vane was not used because of the imbalance of forces on the shaft of the vane. Eight blades was a practical upper limit from the standpoint of difficulty of fabrication. All the vanes had the same dimensions, a H/D ratio of two (H=2.0 inches, D=1.0 inches) and a shaft of 3/16 inches diameter. Figure 3 shows the seven vanes used. 5. Sample Containers Two different sets of sample containers were prepared. The first set of seven containers varied in diameter from 1.611 inches to 10.298 inches. The second set of seven containers was essentially constant in size, with an average diameter of 4.992 inches. All con- tainers were of a depth of 3. 5 inches in order to allow 3/4 inches of sample above and below the vane during testing. Each container was fitted with two opposed slots at their base to ensure that they were securely held during the testing. Figures 4 and 5 show the containers. Packing the material to be tested into the containers required the preparation of the tamps shown in Figure 6. The various diameters of the containers were as follows: 16 Figure 3. Vanes with from Two to Eight Blades Used for Testing Figure 4. Containers 1 through 7 Used for Testing 17 ~* P^^ m~m J- Figure 5. Containers A through G Used for Testing Figure 6. Tamps for Containers 1 through 7 and A through G 18 Container Int ernal Diameter (inches) 1. 611 1. 988 2. 703 4. 298 4. 835 1 2 3 4 5 6 7.837 7 10.298 A through G 4. 992 (average) 19 in. TESTING PROCEDURES All tests were conducted during the months of January and February 1971 at the Naval Postgraduate School. The duration of the majority of tests was ten minutes. Exceptions were: (a) three minutes for motor speeds of five and ten revolutions per minute and (b) one and one half minutes for motor speeds of twenty and thirty revolutions per minute. A. TEST MATERIALS Marine sediments themselves are unsuitable for comparison test- ing of this type in that they continually lose water content and hence increase in shear strength in the drying process. Test materials were therefore required having strengths in the same range as marine sed- iments yet not subject to the evaporative process. The first material selected for testing was wheel bearing grease. In order to verify the results obtained, a type of sculpting clay was also selected. This clay did not have a water base and hence would not dry in air. Because the clay -was originally much stronger than the wheel bearing grease, oil was added to the clay to bring it into the same range of shear strength as normal sediments. An electric hand drill with a paint mixer attach- ment was used to mix the clay and oil together to form a homogeneous test material. 20 B. PACKING THE CONTAINERS The results of the vane shear tests proved difficult to reproduce with the grease, even when the same size container was used, due to non-uniform packing. A method of ensuring uniform packing was there- fore necessary. The smaller containers had a tendency to entrap air resulting in values of shear strength which were lower than the actual values. A similar problem was encountered with the use of the clay. Comparison of series of tests on the two sets of containers (1 through 7 and A through G) was more likely to yield usable results. The relative trends could therefore be compared. This was considered to be a practical approach to the testing because all the containers in the set were prepared nearly simultaneously and in the same manner. A method was devised of placing the containers with the grease into a drying oven, in order to develop a greater degree of uniformity. Temperatures of 86 to 105 degrees Centigrade were used, with the majority of heating at the higher temperature. The containers were usually placed in the oven for at least six hours and then allowed to cool for more than ten hours. This procedure eliminated the air from the smaller containers, for at 105 degrees Centigrade the grease be- haved as a thick liquid. Because the clay might have hardened in the oven, tamps were prepared to fit within each of the containers. The tamps were used in conjunction with a clear plastic household wrapping material. The 21 plastic was used to keep the clay from adhering to the tamp. Great care had to be exercised to ensure that no air remained trapped in the smaller containers. C. TEST PHASES The temperature of the room in which testing was done was assumed to be essentially constant, in that it was located in the base- ment of a concrete building and thus not influenced by the heating of the sun. Both the grease and the oil and clay mixture were assumed to be homogeneous. To hold all but one test parameter constant, three test phases were used for each material. 1. Phase One The first phase of testing required the motor speed and number of blades on the vane to be held constant while the diameter of the container was varied. A motor speed of 1 RPH and a four-bladed vane were used. Containers 1 through 7 were tested during this phase. For the testing of the clay container 5 was not used because it was close in size to container 4. Also, it was slightly out of round which made it difficult to pack. 2. Phase Two Phase two involved the fixing of the container size and motor speed while varying the number of blades of the vanes. The essentially constant diameter containers A through G were used with a motor speed of 1 RPH. The vanes were varied from two to eight blades. 22 3. Phase Three The third test phase used a constant container size and a fixed number of blades with a varied motor speed. The four-bladed vane, containers A through G, and motor speeds of 1, 2, 5, 10, 20, and 30 RPH were used. 23 IV. RESULTS OF TESTS A. COMPUTATION OF SHEAR STRENGTH From the shear strength formula of Cadling and Odenstad [1950] M g _ max /TTDH D + 2TTD^ 2 D \ I T ~4~ 3 T I it can be seen that the denominator is a constant for the seven different vanes that were used. With H=2.0 inches and D=1.0 inches its value is 3.6652. By setting the fixed 125 inch-ounces output of the amplifier equal to 0. 5 volts the following relationship is established: 125 inch-ounces =0.5 volts = 500 millivolts. Therefore 1 inch- ounce = 4 millivolts = 4 mv. Since all values of M were obtained in millivolts, to compute max r shear strength in pounds per square inch (psi) the following factor was applied to the M in millivolts: r max 0 , .. , , , . 1 in. -ounce 1 1 pound S (psi) = M (mv) x x — — 3 x ti^ • max 4 mv. 3. 6652 in. 16 ounces Occassionally shear of the sample did not occur during the time allotted for the test. In these cases the maximum value of torque attained by the end of the test was used for computing the shear strength. Because the duration of each test was not varied, but fixed for particular motor 24 speeds, this was considered as a valid figure for comparison purposes The results of the tests are given in Appendix A and are summarized in Tables I through VI. 25 Table I. Summary of Results of Phase One Tests Using Grease Run Speed No. of Container Shear No. (RPH) Blades Strength (psi) 56 1 4 1 .364 57 it it 2 .464 58 ii ti 3 . 334 59 it ti 4 .2245 60 ii it 5 .220 61 ii ti 6 . 1404 62 ti ti 7 . 151 63 1 4 1 .441 64 ii it 2 . 340 65 ii ti 3 .217 66 it ii 4 .3015 67 it it 5 .288 68 it it 6 .212 69 it it 7 .2045 70 1 4 1 .2565 71 it it 2 .218 72 it it 3 .216 73 it it 4 .2345 74 n it 5 .207 75 it it 6 . 198 76 it it 7 .2457 77 1 4 1 .294 78 it it 2 . 319 79 it it 3 .268 80 it ii 4 . 1947 81 ti it 5 .2715 82 ti it 6 .2215 83 it ti 7 .258 84 1 4 1 .264 85 it ti 2 .287 86 ti it 3 .2255 87 n ti 4 .2235 88 it it 5 .250 89 it it 6 .2325 90 ti it 7 . 1988 26 Run Speed No. of Container Shear No. (RPH) Blac ies Strength (psi) 91 1 4 1 .286 92 2 .264 93 3 .231 94 4 .2295 95 5 .242 96 6 .206 97 7 . 197 98 1 4 1 . 302 99 2 .306 100 3 .2765 101 4 .2063 102 5 .2115 103 6 .2283 104 7 .2182 27 Table II. Summary of Results of Phase One Tests Using Clay Run Speed No. of Container Shear No. (RPH) Blad es Strength (psi) 170 1 4 1 .2217 171 it it 2 . 195 172 ii it 3 . 183 173 ft it 4 . 160 180 1 4 1 .206 181 ti it 2 .2383 182 it ii 3 .2742 183 tt it 4 .2313 184 it it 6 . 1867 185 it ii 7 . 180 222 1 4 1 . 305 221 it it 2 .268 220 ii ii 3 .2593 219 it it 4 .2183 218 ii tt 6 .2015 217 it ti 7 . 1818 28 Table III. Summary of Results of Phase Two Tests Using Grease Run Speed No. of Container Shear No. (RPH) Blades Strength (psi) 105 1 2 A .226 106 ii -3 B .297 107 it 4 C .2975 108 it 5 D .2767 109 ii 6 E .2467 110 ii 7 F .3275 111 it 8 G .2165 112 1 2 . A .2515 113 ii 3 B .2465 114 ii 4 C .300 115 ii 5 D .293 116 it 6 E .294 117 ii 7 F .386 118 n 8 G .285 119 1 2 A .2235 120 it 3 B .2403 121 ii 4 C .280 122 ti 5 D .272 123 ii 6 E .2335 124 ii 7 F .334 125 ti 8 G .2597 126 1 2 A .2155 127 it 3 B .227 128 ti 4 C .248 129 it 5 D .240 130 it 6 E .2495 131 it 7 F .281 132 ti 8 G .2617 156 1 2 A .2745 157 it 3 B .2896 158 it 4 C .247 159 it 5 D .2675 160 ti 6 E .264 161 it 7 F .2995 29 Table IV. Summary of Results of Phase Two Tests Using Clay Run Speed No. of Container Shear No. (RPH) Blades Strength (psi 189 1 2 A . 176 190 3 B . 1985 191 4 C .208 192 5 D .242 193 6 E .2173 194 7 F .213 195 8 G .215 203 1 2 • A . 166 204 3 B .238 205 4 C .220 206 5 D .2173 207 6 E .237 208 7 F .242 209 8 G .2295 30 Table V. Summary of Results of Phase Three Tests Using Grease Run Speed No. of Container Shear No. (RPH) Blades Strength (psi) 133 1 4 A .2735 134 2 ji B .279 135 5 ii C .279 136 10 ii D .3215 137 20 M E .400 138 30 II F .429 144 1 4 A .222 145 2 it B .2185 146 5 ii C .2755 147 10 ii D .329 148 20 ii E . 3405 149 30 n F .380 174 1 4 A .284 175 2 ii B .274 176 5 it C .294 177 10 it D .3935 178 20 it E .432 179 30 ii F .3493 31 Table VI. Summary of Results of Pha se Three Tests Using Clay- Run Speed No. of Container Shear No. (RPH) Blades St :rength (psi) 196 1 4 A .2268 197 2 - ii B .2259 198 5 C .266 199 10 D . 3245 200 20 E .2595 201 30 F .281 211 1 4 B .2295 212 2 . C .2355 213 5 D .2723 214 10 E . 3405 215 20 F .364 216 30 G .3313 32 B. RESULTS 1. Phase One Tables I and II summarize the results of phase one tests in which the motor speed and number of blades were held constant while the container diameter was varied. Figures 7 through 16 show the plots of shear strength versus container diameter. Five of the ten series of tests conducted during this phase showed an increase in shear strength from container 1 to container 2 along with subsequent isolated instances of increase. The overall tendency was, however, for shear strength to decrease with increasing container size. Figure 12 for the grease and Figure 16 for the clay are representative of the relative decrease in shear strengths. The solid line in Figure 12 is based on the discounting of the value of shear strength for container 5. Figure 14 shows only four points because a sufficient quantity of clay to fill all the containers had not been mixed when the testing of the clay was started. 2. Phase Two The results of the phase two tests are summarized in Tables III and IV. In this phase the number of blades was varied while the container diameter and motor speed were held constant. Figures 17 through 23 show the plots of shear strength versus number of blades. The vane with seven blades gave results which were generally too high. This was apparently caused by a slight eccentricity in the rotation of the vane. The results of the seven-bladed vane were thus 33 CO a •m O in en 0) U id •w Q u 1) C c o U CM vO I vO m CO C p* *■? 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I— < cu a • I-l 46 o in n CN tn a H i— t 4) ffl ,0 O s h Z GO M -t-> W u ,c CO o CM m DO C CD M -4-> CO M CO m (xsd) q;§u3j;g j^aqg CN] 0) 48 CO i— i U m <— i i oo en C m CO CD cc! »— i CO cu rd i— i CQ O Ih cu CU a 0 0 CO CO m m QJO c cu u CO M cu CO in ^ ro c« (tsd) q;Suaa:;s J^^S CM (M cu u W) • H fa 49 to •ft * m fN i-H u o (M m o 0) 5 en 0) nJ i— i CQ O 0) «*H h O 2 ^ £ 0) XI CO a 3 CO p h z CD > 0) to. h n) CD CO ro 0) •IH (isd) n;§u3j;s JB9i{s 50 discounted. All the plots of shear strength versus number of blades showed a maximum in the range of three to five blades. Vanes with over five blades gave lower values of shear strength. This is believed to be caused by the increased amount of disturbance near the shaft of the vane when the vane was inserted into the sample. The larger hole left in the sample after removal of the vanes served to verify this conclusion. 3. Phase Three Summarized results of tests of phase three are given in Tables V and VI. In phase three container diameter and number of blades were held constant while the motor speed was varied. Plots of shear strength versus motor speed are shown in Figures 24 through 28, Shear strength generally increased with increased motor speed. The values of shear strength for the 1 and 2 RPH speeds were in close agreement with a definite increase in shear strength occurring at speeds above 2 RPH. 51 138 13 7^ 135, en W.2 u 0) 1 10 Motor Speed (RPH) 20 30 Figure 24. Shear Strength versus Motor Speed, Runs 133-138, Grease 52 .5 149 148, 147- en a c U a 0> CD -4-> m •* ^ ■* ^ -* o o »H vO vO fO N N ^ ifl CO -^ CO 00 (VJ ■— I i-t ID ID h O [^ h 00 N ^ tP "tf <-* O 00 i-l o ^ fO (M M N N N in ir> r- vo oo vo Tf r- oo m if) i— • t-t CO O 0s rf c\j ro cm cm cm — i cm m o vO oo vo o in v£> O O 00 00 O rH cm cm r- — i Is- m r- m o oo cm >— i co in oo o Is- m in co co co o '-* o c*- o oo o oo m t*- vc Tt Tf o i-t o in oo so r- vo in in in ^ *t m M co I— 1 2 03 ffi CD Ph Ph rt C/J CD CO 0) OX) CO nJ 0) u 00 co cd 0) rt A a) CO. ^ r*- in m rt* a- oo i* h h oo o^ •-< so o r^ cm u^ cm CO cm — i CM CM CM in m m co tC i-- in m o n oo ■o co cm cm in co o^ CM cm cm CM CM CM i-H in vo rt* >-h 0s cm vo r- 00 vO co cm -^ o o~- CM CM CM CM CM CM ■-• CO. 1 9 O O O t»» CO o o o m o m p- r*- r- cm o co o o 00 CO o^ in co in co cm o vD Is- vO ^f vD in vO cm r- co oj oo Tf so o so m in m m ^ r- cm -^ co r- oo vo vo vO in in in •*? •*& v • H * o U •"HcMco^invDr- --•cMco'^invOh- h n m ^ ^ >o [^ *M W 0 a> X! o 03 f— i £ ffl •X) >r> O t-H u ft co £■ a; CO a) GO CO aJ V u 60 0) co vi W) 2 o r- co cr» o •— i cm co Is- r- C- co oo co oo -^ m so r- co o o oo co oo oo oo co o <-* CM CO rt< lO vO "Is- QN 0s Qn Qx O^ O"* 0s 64 00 ft CO en in co in co cm m r^- r^ in in n vo \o so h co oo vo r- r>- o o r>- o OOr^O^HCM--" N O^ O^ [^ ■* N ^ CO f) N N N N N N N N N N ro N IT) IT) ■— • v£) O cO rt* vO in m ^ o o^ o oo oo CM CM CO CM CM CO CM I o o o in r- t- co <— i co o^ ■— i o o o^ >— i o m o cm Is- o r-i CM in 00 O CO •— I r- Is- vo -^ "* in m co o^ o^ in co r> o m vo vo so in I*- in o co o oo a*- o r- in in Is- so so o vD u i-h V Pm ft pr; CO CO co u so co CO CO CO oJ <0 !h CO O^ O >-l CM CO ^ O^ O^ o o o o o in vo > oo o^ o o o o o o <-* ■-H n co 11 m ^o > co 65 09 P. *~* u X (4 4-> on CD rt X r<- N O N cm cm cm co - CO vD r-i in in in in in no so rf in in m ^ H vO vO nO C^ 0s q u a * o U <«OQWhO - 00 O O •— I CM cm cm cm cm co co co co tJ< in o r>- co CO CO CO CO CO CO 66 01 # W) in u m in in cm co in o^ o o cm —* r- cm rt1 co cm cm cm co m co m vo m in ■* o > h- rf a^ r-. oo -^ so v£> a^ - o o co ^ cm CM CM CO t}* CO t-H CO v£> CO O CO m o o co o co o co O vO so co o co in o CM <-• ^ Is- O O^ in m vo Is- co co ■ttf CO 00 CM (M O vo so in vo so e- cm in co r*- in -tf -^ co sO ■** O^ CM — • CM v£> vO vO O^ O 00 u -h ro (M rj cnj r\j co o to m vo m vo -^ o •— i N N vO N in CO ro f\J c\j co rg cnj co in vO co o f- C*- ro o sO CO f\J ■-• CO ^' CM H N (M N (\J N (\3 •^ o -^ CO CO CO co vo co in o o m co o m oo 0s o o 0s vo o r*- co a^ CO \D •* ^ fO N ^ m vo in ^ 1* •— • vD CO sD •— I O O ^r ^ ^ in in in in CO CO f\J vO O vO m m vo r^- vo vo o m •— i ■— i in r- co co in in in m m in u 0) p • iH a o U -Hcxjco^vot- XS 0 e— 1 Z PQ cm co tj< in vo t— co co % Ph W 3 ro m o o o iH <\J CO n) - - P . P O Ph £ o i-h ro co ^f in co co co oo oo co o o i-h co co *tf m oo c^ f> 0s o^ 0s Cf> vo Is- oo cr- o i-h '-H i-H r-4 H ro oo fO rt1 in vO h co f> o o o o o o o ro oo oo ro ro oo ro 68 OX) ti CO. in in co in co 0s in co o ^ *— i co co r- ^ vo co CO (M co co co co oo in co co h h co ooo m oo o •-* m vo o -< N N N N ro 1 o co o o in go Is- CO CO 0s O vO co in -^ o m r- m in \0 oo oo h OJ ("» — I O CO i-H ^ ^ in vo so > u c o U ffl U Q H h O r-vo^cocvj^H ■H to O d> d ^ £ PQ o) ft CO. C- ih co m o o o t-« CO CO 2 O Pi £ ih ro co rf m vo i— i i— i i— i •— i i—i i— i N N N N N N t- 00 O O i-i CO h H h N (M N N N (M N N N 69 BIBLIOGRAPHY Aas, G. , "A Study of the Effect of Vane Shape and Rate of Strain on the Measured Values of In-Situ Shear Strength of Clays", Norwegian Geotechnical Institute, Publication No. 65, p. 5-9, 1965. Cadling, L. , and Odenstad, S. , "The Vane Borer, An Apparatus for Determining the Shear Strength of Clay Soils Directly in the Ground", Royal Swedish Geotechnical Institute, Proceedings No. 2, 195CL Heck, J. R. , Engineering Properties of Sediments in the Vicinity of Guide Seamount, MS Thesis, Naval Postgraduate School, Monterey, California, 1970. Minugh, E. M. , A Versatile Vane-Shear Apparatus, MS Thesis, Naval Postgraduate School, Monterey, California, 1970. Morelock, J. , Sedimentation and Mass Physical Properties of Marine Sediments, Western Gulf of Mexico, Ph.D. Thesis, Texas A&M University, May 1967. Osterberg, J. A. , Introductory Comments, Symposium on Vane Shear Testing of Soils, American Society for Testing Materials, Special Technical Publication No. 193, 1957. Smith, R. J., "Engineering Properties of Ocean Floor Soils", ASTM Symposium on Field Testing of Soils, American Society for Testing Materials, Special Technical Publication No. 322, 1962. 70 INITIAL DISTRIBUTION LIST . No. Copies 1. Defense Documentation Center 2 Cameron Station Alexandria, Virginia 22314 2. Library, Code 0212 2 Naval Postgraduate School Monterey, California 93940 3. Professor R. J. Smith, Code 58Sj 1 Oceanography Department Naval Postgraduate School Monterey, California 93940 4. LT James Charles Singler, USN 1 U.S. Atlantic Fleet AS W Tactical School Norfolk, Virginia 23511 5. Professor J.J. von Schwind 3 Department of Oceanography Naval Postgraduate School Monterey, California 93940 6. Oceanographer of the Navy 1 The Madison Building 732 North Washington Street Alexandria, Virginia 22314 7. Commander 10 Naval Facilities Engineering Command Code 03 Washington, D. C. 20390 8. Department of Oceanography (Code 58) 3 Naval Postgraduate School Monterey, California 93940 71 Unclassified Security Classification DOCUMENT CONTROL DATA -R&D* {Security classification of title, body ol abstract and indexing annotation must be entered when the overall report Is classified) I originating activity (Corporate author) Naval Postgraduate School Monterey, California 93940 la. REPORT SECURITY CLASSIFICATION Unclassified 2b. GROUP 3 REPORT TITLE The Effect of Varying the Parameters of Vane Shear Tests on Marine Sediments 4 DESCRIPTIVE NOTES (Type of report end. inclusive dates) Master's Thesis; March 1971 5 AUTHORISI (First name, middle initial, laat name) James C. Singler 6 REPOR T O A TE March 1971 la. TOT»l NO. OF PAGES 73 76. NO. OF REFS %m CONTRACT OR GRANT NO. 6. PROJEC t no 9a. ORIGINATOR'S REPORT NUMBERIS) 96. OTHER REPORT NO(S) (Any other numbers that may be assigned this report) 10 DISTRIBUTION STATEMEN' Approved for public release; distribution unlimited. II. SUPPLEMENTARY NOTES 12. SPONSORING MILITARY ACTIVITY Naval Postgraduate School Monterey, California 93940 13. ABSTR AC T The consequences resulting from varying the parameters of the vane shear test (used to determine the shear strength of marine sediments) were investigated. Experiment showed that larger ratios of container diameter to vane diameter yield more accurate shear strengths. It was also shown that the four-bladed vane produced the best results. Finally, rates of rotation of one and two revolutions per hour were found to give accurate values of shear strength, while higher rates of rotation proved to be unsatisfactory. DD,r:..1473 ,PAGE " IOV 69 S/N 0101 -807-681 1 72 Unclassified Security Classification A-3140S Unclassified Security Classification key wo RDJ Vane shear testing Shear strength Marine sediments Sediment testing DD ,Fr,"..1473 (b*ck, S/N 0101-807-682) ROLE "T Unclassified 73 Security Classification A- 3 I 409 c 240CT72 '2 APR73 22 8t40 21 8/j o stngier "26894 fce Parj^LCt of vary, Sp,fr fests 0rt Va^e III Thesis S5385 f 1 126894 Singler The effort of varying the parameters of vane shear tests on marine sediments. thesS5385 The effect of varying the parameters of 3 2768 001 91441 9 DUDLEY KNOX LIBRARY