STRESS TRANSFER DUE TO CREEP EN A SAW-RATED CLAY The“: for ’rE-te Dogma GE M. S MICEEE SAN STALLS LNZ LEE? Sui" 3'- iahk J. L‘Emfiday E963 masts LIBRARY Michigan State University ABSTRACT STRESS TRANSFER DUE TO CREEP IN A SATURATED CLAY by Frank J. Holliday An experimental study was made to determine the behavior of friction and cohesion in a clay soil during creep. Creep-CPS tests were used to determine cohesion and friction at the end of different periods of elapsed creep time. The results were compared with the stress transfer curves calculated from Creep tests. The increase in friction and decrease in cohesion with creep time measured with the Creep-CPS test were similar to the increase in frictional resistance and decrease in cohesive resistance computed from the Creep test° The behavior of the frictional and cohesive components can be represented by the elastic and viscous elements of the Kelvin rheological model. 'STRESS TRANSFER DUE TO CREEP IN A SATURATED CLAY by I.) y E’ Frank,J.KHolliday A THESIS Submitted to the College of Engineering of Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Civil Engineering 1963 ii ACKNOHLEDGEMERTS The writer is indebted to Dr. T. H. wu, Department 6f Civil Engineering, for his guidance, assistance, and encouragement through- out the writer's Master's Degree program. Thanks are expressed to A Dr. 0. B. Andersland for time spent with the writer during Dr. Hu's absence and to‘the writer's colleagues, A. K. Lab and R. w. Christensen, for assistance in and out of the laboratory. The writer wishes to express his appreciation to the National Science Foundation for the Graduate Research Assistantship which made graduate work at Michigan State University possible. I. II. III. IV. VI. VII. TABLE Q§_CONTENTS INTRODUCTION . . . .......... APPLICATION OF RHEOLOGY 2.1 2.2 Maxwell and Kelvin Models . . . Elastic and Viscous Elements . . . 2.3 Application of Kelvin Model to Saturated Clay . . . EXPERIMENTALPROGRAM. . . . . . . .. 3.1 3.2 3.3 3.4 3.5 RESULTS CONCLUSIONS . . . 5.1 5.2 BIBLIOGRAPHY . . . .' . Determination of To Determination of ‘1’.) Soil Used . . . . . . . . . . . . Sample Preparation . . . . . . . Triaxial Tests . . . . . . . . . Validity of Kelvin Model . . . . Suggestions for Future Study . . mm“ 0 O O O O O O O O O O O O O O 7.1 7.2 7.3 7.4 7.5 O O O O O Derivation of Data Table for CPS Test Typical Data for Tests Run . . . . . . . . . and «2, from Creep Test . . and‘fie from Creep-CPS Test Calculations for G1» and c' for Conpacted Clay Calculations for G1; and c' for Consolidated Clay. Sample Calculations for c' from Creep-CPS Test iii Page 10 10 10 13 20 20 32 37 37 37 38 40 40 40 69 70 71 Table 1. 2. 10. 12. 13. 14. 15. 16. 17. .18. 19. 20. 21. 22.. 23. LIST 9}; news Properties of Sault Ste. Marie Clay . "8" Parameter Test Data . . . . . . . Summary of c' and «’4; Values . . - . Summary of Triaxial Tests . . . . . . Triaxial Test Results at End of Tests General Data Sheet (Test C-CPS-l) . . Consolidation Data Sheet (Test C-CPS-l) cps Data Sheet (Test moss-.1) . . . . CPS Data Summary (Test CHCPSél) . . . General Data Sheet (Test F-CPS-l) . . Consolidation Data Sheet (Test P-CPS-l) CPS Data Sheet (Test F-GPS-l) . . . . CPS Data Summary (Test P-CPS-l) . . . 0 General Data Sheet (Test 6-0-7 3. C-C-CPS-7) . . . Consolidation Data Sheet (Test C-C-7 a Caz-crest) Creep Data Sheet (Test C-C-7) . . . . . . . . . . CPS Data Sheet (rest O’C.CPS.7) Q 0 O O 0 O O O 0 :CPs Data Su-ary (Test C-C-CPS-7) . . . . . .. . . General Data Sheet (Test 'P-C-1 s P-C-CPS-l) . . . ConsbliEdation Data Sheet. (Test sac-1 r P-C-CPS-l) Creep Data Sheet (Test F-C-l) . . . . . . . . . . crs Data Sheet (Test P-C-CPS-l) . . . . . . . . . CPS Datasumxy (T281: P'C'CPS'1)'0 s s o o o o 0. iv Page 10 14 22 23 25 42 43 47 49 50 E51 53 55 56 57 53 so 62 63 64 66 67 LIST 9g FIGURES Figure Page 1. Spring or Elastic Element . . . . . . . . . . . . . . 4 2. Dashpot or Viscous Element . . . . . . . . . . . . . 5 3. Shear Strain Versus Time Curve for Maxwell Model . . 6’ 4. Kelvin Model . . . . . . . . . . . . . . . . . . . . 7 5. Shear Strain Versus Time Curve for Kelvin Model . . . 8 6. Stress Transfer Curves for Kelvin Model . . . . . . . 8 7. Compaction Apparatus . . . . . . . . . . . . . . . . 11 8. Division of Compacted Cake . . . . . . . . . . . . . 12 9. Creep Test . . . . . . . . . . . . . . . . . . . . . 15 10. Schematic Drawing of CPS Test . . . . . . . . . . . . 16 11. CPS Test . . . . . . . . . . . . . . . . . . . . . . '18 12. Creep-CPS Test . . . . . . . . . . . . . . . . . . . 19 13. Mohr's Circle . . . . . . . . . . . . . . . . . . . . 21 14. Creep Curve for Compacted Clay (Test C-C-7) . . . . . -26 15. Creep Curve for Consolidated Clay (Test P-C-l) . . . 27 16. Extrapolation of’ ¢f for Compacted Clay'. . . . . . . 28 17. Extrapolation of 49’ for Consolidated Clay . . . . 30 18. Stress Transfer for Compacted Clay . . .-. . . . . . 35 19. Stress Transfer for Consolidated Clay . . . . . . . . 36 20. Mohr's Circle for CPS Test Data Table . . . . . . . . 40 21. Typical Stress-Strain Curve for Compacted Clay Creep-CPS Test (C-C-CPS-6) . . . . . . . . . . . 41 vi Figure Page 24. Stress-Strain Curve for Test C-C-CPS—7 . . . . . . . 61 25. Stress—Strain Curve for Test P-C-CPS-l . . . . . . . 68 vii NOTATION ¢'= Axial stress 6 = Axial strain E = Constant associated with spring é = Strain rate °<= Constant associated with dashpot W'= Maximum shear stress ‘6 =-" Maximm shear strain G = Constant associated with spring 3 = Constant associated with dashpot Time Shear stress in spring Shear stress in dashpot s Constant maximum shear stress sheen II Shear stress associated with friction «2.: Shear stress associated with cohesion A 9 a C3) = Principal stress difference 431 u Friction Cohesion 0 ‘ II ’ Effective axial stress 9 | ([3: Effective radial stress Shear strain at time of negligible,strain rate Threshold value of shear stress r< :9 4% II Shear stress due to creep load ; INTRODUCTION Soil engineers have had the problem of creep during sustained loading of clay soils for many years. Buisman (1936) noted that results of long duration tests on peat and clay showed total deforma- tion resulting from a combination of deformation due to "direct load effect" and a "time dependent" deformation. Buisman observed "Continuously decreasing deformation" in the consolidation process and termed this phenomenon the "secular" effect. Geuze (1948) later reported that Buisman's "secular law" was followed during the Con- solidation process and at low values of shear stress by cohesive soils. Casagrande and Wilson (1950) presented data from two types of tests (creep strength tests and long time compression tests) showing clearly the time effects on deformation and strength of clays. The loss of strength with time observed in saturated clays could account for slides on slopes which failed after standing for many years. Geuze (1953) and Haefeli (1953) presented field observations of soil failures after excessive creep. Terzaghi (1953) pointed out that little was known about creep and stated that much research and study was needed in this area. The recognition of the creep problem led to application of the theories of rheology in an attempt to describe mathematically the creep in soils. Vialov and Skibitsy (1957) (1961), Geuze (1953), Geuze and Tan (1954), Haefeli (l9~5'3)and Schiffman (1959) presented ‘- papers on the rheological analysis of deformation. Murayama and Shibata (1961) proposed a four element rheologic model to explain the viscosity, elasticity and internal resistance of clays. Rowe (1957) presented a hypothesis suggesting that "creep will lead to a gradual increase in the pressure on structures which resist movement, the ultimate pressure being that due to soil having only friction." This suggests that as creep progresses the value of cohesion should decrease to a small value or zero and values of friction should increase. This hypothesis was substantiated by Schmertmann and Hall (1961), Wu, Douglas, and Goughnour (1962) and Bea (1963). They showed that cohesion and friction during creep followed time dependent relationships that are visco-elastic in nature. The soil parameters friction and cohesion are defined according to Schmertmann and Osterberg (1960) as follows: Priction - The angle of internal friction, at any strain, is the angle whose tangent is the ratio of the change in shear stress to the change in normal intergranular stress occurring on the plane of Mohr envelope tangency at that strain, during a stress change occurring without significant change in soil structure.' Cohesion - The cohesion of a soil, at any strain, is the shear stress developed on the plane of Mohr envelope tan- gency at that strain, if the intergranular stress on that plane could be reduced to zero without signifi- cant change in soil structure. It is the objective of this research to study the behavior of friction and cohesion of a clay soil during creep as elastic and viscous resistance components of the material to deformation. One of the simplest rheologic models of viscorelastic behavior is the Kelvin model. Although the Kelvin model does not completely describe the Complex nitfiie of creep, its simplicity is an advantage in establishing a first approximation of the action of cohesion and friction during deformation. ' LI; APPLICATION Q; RHEOLOGY 2.1 Elastic and Viscous Elements The rheologic behavior of materials is represented by visco- elastic models consisting of dashpots and springs in series or parallel. The elastic solid is represented by the spring and the viscous fluid is represented by the dashpot. Figure 1 shows the schematic of a spring and Figure 2 shows the schematic of a dashpot. q. , V Figure l - Spring or Elastic Element The equation for linear elastic behavior represented by the spring in Figure 1 is Where a; u Axial stress, m I! Axial strain, I?! ll Constant associated with spring. Figure 2 - Dashpot or Viscous Element The equation for viscous fluid behavior represented by the dashpot in Figure 2 is Where Q'= Axial stress, é.= Axial strain rate, a'(=-"Constant associated with dashpot. Application of this concept of the rheologic model to soil mechanics requires the assumptions of continuity and homogeneity. Under the condition of no volume change all deformations are the result of shear stresses. The deformations under a set of principal stresses can be correlated with the shear stress. By applying the above conditions the equations for the elastic element and viscous element become reapectively: (V: G}! . (2.1-1) (Vega. (2.1—2) Where ‘1’: Maxim shear stress, '6 = Maximum shear strain, G = Constant associated with spring (shear modulus), 3>= Constant associated with dashpot (viscosity), t = time. 2.2 Maxwell and Kelvin.Models Series arrangement of the spring and dashpot is called the Maxwell model. The Maxwell model's characteristic shear strain versus time curve is shown in Figure 3 where ‘r/G is equal to the instantaneous shear strain in the elastic element under a constant shear stress condition. Shear Strain Maxwell Creep LA; Curve Time Figure 3 - Shear Strain Versus Time Curve for Maxwell Model The parallel arrangement of a spring and a dashpot is called the Kelvin (or Voigt) model. Figure 4 shows a schematic drawing of the Kelvin model. Figure 4 - Kelvin Model Since the strain in each element of the Kelvin model is equal to the total strain of the model and the sum of the shear stress in each element is equal to the total shear stress on the model, the follow- ing equations apply: q2{=(375 we _ Hm> a _: e A. «m E. HITN: GOPw I msowom I. m use. Homo—.8 . . Toma 33:8 . mun—momma. otonmm 1M mac snowman _ _ whom wmwcmoa Hosanna — i Hamo m . Hewxmwue r m r a Haoo Hmwa .kJN.amm mhmwmomm :wmuum ummummoo dawn .. W a was“ . ammo movsmom use; wmw>onm 17 The test was run at a constant strain rate of about 0.3 percent strain per hour. During the test the strain rate varied between 0.8 percent strain per hour and about 1.0 percent strain per hour. Schmertmann (1962) reported that small changes in strain rate did not affect friction and cohesion. Preliminary tests run by A. K. Loh and the writer show that increases in strain rate from 0.5 percent strain per hour to 1.0 percent strain per hour increase cohesion by 29 percent and decrease friction by 27 percent for the clay soil used. During the test it was necessary to keep the difference in principal stresses (fin - “3) matched by an equal change in pore pressure. Matching of (V. - T3) by a change in pore pressure held the effective axial stress ( 0‘, ) constant and continually changed the effective radial stress (3’3). At specified intervals the weight on the constant pressure cell in the pore pressure stage was increased or decreased by a predetermined increment. An increment of 0.5 kilogram per square centimeter in the porewater pressure was used. This produced an equal and opposite change in (0'. ) and (Q‘s ).1 Under the new ('0', ) the deviator stress (0“ - W3) behaved differently and the pore pressure was adjusted so that it was equal to the new (0', - 03). When the matching operation and the weight changing operation were superimposed a ( U" - 0‘3) versus social strain curve was obtained for each level of ( i" ). Using Mohr's circle and the theory of effective stress, the friction ( (V ) and cohesion (c') at various axial strains were com- puted. These computed values were then plotted to give friction and* cohesion versus axial strain curves. Figure 11 shows CFS test set up. 18 a ‘o‘ né. 9 L... 139 r . 'fi-‘I1 _; ,.' ““ Figure 11 - CFS Test Measurements recorded during the test were ( V. - 03), axial strain, and elapsed time. Early in the test these measurements were recorded after each 0.001 inch of axial deformation and later at increments of 0.1 percent axial strain. The proving ring was read continuously during the test and (Q, - (1'3) calculated. Corrections for change in area due to axial strain were made continuously. Bach calculated value of (V. - 03) was matched by the pore pressure. The equation used to calculate ( W. - 05) was (0’ -< who Imoono who Immouo who Immouo who Insane who Immouo who umoouo who nmoouo who Imoouo who nmoono who nmvouo Imoouo mmo waxy 0.8a o.N o.N o.N o.N o.u o.N o.N o.N o.N o.~ o.N o.N au¢bem I ¢ mHm¢H N.H¢ o.u¢ 0.N¢ w.H¢ m.~¢ c.N¢ v.Nw ¢.N¢ v.u¢ H.N¢ N.H¢ o.mv N. noun: H353 3&3 «H ¢H wH 0H 00000000000 79.8.0.0 2-96.0.0 3-2990 5.20.0.0 $290.0 793.90 9.93.0.0 4.20.0.0 0.98.0.0 9.3990 4.10.0 HI who: u .mwwma 08.... 24 0.3. 3.0.0 «.3 cu." mH.H 3.0 10030 0.0 5.0m 0.3 H m 72010...” who «$5 ca. 3 34 36 -020 cé fig 5.3 m m 99.8.9.1 mmo 03.0 «.0 v mH.H 0H.H 10030 0.~ oém 0.3. N 0 «1300.0 . who 03.0 .06 H mH.H 0H.H 1000.5 o.n Tum 2.3 v 0 4120.010 o2 34 06.5 o& 8.»... 5.8. a .1 all oN.H who o.u mém 0.2.. m m Hummoum ~30 ama< Home 13980 Hugh H335 3055 “Boy. 529200 . v 5049 Test Desig. C-CPS -l C-C-CPS -S C-C-CFS -3 C-C-CPS-4 C-C-CPS-6 C-C-CFS -l C-C-CPS-S C-C-CFS-9 C-C-CPS-lo C-C-CFS -ll C-C-CPS-7 P-CPS -l P-C-CPS-4 P-C-CFS-2 P-C -CPS -3_ P-C-CPS-l TABLE 5 - TRIAXIAL TEST RESULTS AT END OF TESTS Strain % 8.0 6.0 6.0 6.0 6.0 3.0 6.0 7.0- 6.0 6.0 7.0 9.0 9.0 8.0 6.0 9.0, 1.42 1.41 1.42 1.34 1.60 1.17 1.69 1.67 1.57 1.44 1.42 1.71 1.71 1.65 1.51 1.41 2.00 2.38 2.20 2.05 2.49 1.75 2.72 ~ 2.59 2.48 2.20 2.14 2.50 2.63 2.55 2.27 2.04 Upper Curve «L"V Kg/cm Kg/cn Kg 0.58 .97 .78 1.03 .92 .91 .72 .79 .92 .90 .76 .63 f... Lower Curve Egg/:1: ngcm" Kg/in" 1.86 1.75 0.39 1.33 1.88 .55 1.32 1.70 .88 1.21 1.55 .34 1.47 1.99 .52 1.11 1.50 .89 1.56 2.22 .66 1.55 2.09 .54' 1.44 1.98 .54 1.83 1.70 .87 1.29 1.64 .85 1.51 2.00 .49 1.58 2.18 .60 1.48 2.05 .57 1.81 1.77 .46 1.23 1.54 .81 ' 25 I c Kg/cn" Deg. 0.538 .563 .537 .475 .546 .430 .561 .600 .534 .541 .500 .459 .470 .476 .386 .433 7.8 5.0 6.8 8.3 9.0 7.8 8.9 7.5 8.9 7.1 8.6 14.6 12.9 12.5 15.0 12.0 26 ‘ ~30 amsodmxoo mom E00 mung—0 I «H gun—E . 39:5": 5 on: 0030 8.3 . 8.3. . 8.3 . cows . 8.2 . 93 o «504 84 u 30 - .3 3.3 .54 3 632. 63 3.0 o 1 olIIIIIIOII|\\ “ . ‘P a 0 P1 0% 0'8 x u: nuns 19m 27 a¢A0.0uh¢0HA00200 ¢0h m>m=0 mmum0_l 0H mm=0Hh movnuwx aw onus moouo 76 III nuns 12va r 8.: 8.3 . 3mm 7 83 3...» 8m" . 8M: . 2.0... e .. d l q 1 1 I 1 I 4 u d u o .unmo H00 0.0 no 0093:0839 mu: w» ”302 . «53. 34 n 30. 60 w. mum: mom pH oHnua mom . H1010 A. _ e—._Tm6 \\ 0 2\\x\\ \O\ 8 \O‘l‘“. .0 O\e\o .\\\\ 8.11.. .0 L. 28 :20 3.0.20.8 mom .0 mo 2393.055 .. 3 5:5: a 5.1 52% u 5 £23 0 one cum on“. om. cm on o... 0 one on» a? on» on“ PA o0 m8 . . . ..- Mn 9 .. A: 3 8.2. .088 .. .0: 3 SE 08.5 .0. a HlemQuolo 0Hlmmololo 0 l 0 T? o I o .7 N ”7.; 9m. n7... 3.0 g T? S on u x "e / 3 s 3 a / 9 u 5. a a :0 a a.“ u: 0 fl . _ "0. s .01 :1 0. 0 o L .r L.“ N 5H 3.3.30 .0 N 5 50.50 .0 0 o .10 o n... c .0. o .m c .w o .H o 0 c we o ..m o .0 o ..m a .0 cm o- a m. w 04 we 0 .H: 0 032. 000.5 . .H: u 0.50. 000M...» \ 4 6-20.0.0 . .1 0.20.0.0 .16 3| WQoN "060+ O o t. \ \ t. 0 ...7 u . .00". V1. .0 X t. X S S u 3 / / a a a 9 “3 fl “2 .r 1.0 1 0 a a a mu: 08 fl 0 I ...O 0 saazflaa u; » saafiaa u]: IQ 29 filo}: :H .o 36 3.0 mné .n" o 7 m 0 2 I. 7. 6 7m .1 .0. mm. 5 4m. mwm 0. CC .. . 4 L... 3 .nw 2 .nm 1 .u m m u m o ooaow on 94 on a 33on 5.0 CONF‘IWED FIGURE 16 CV in Degrees Strain in X FIGURE 17 - mmomnou or 4! FOR CONSOLIDATED CLAY :- 2T 2*: ”I d. *- eq. P-C-CPS-4 / Creep Tine 1 Hr. / I I (I): 0.4 Ci : : t % : 1* :- 0 1 2 3 4 5 6 7 8 Strain in X 3. 6!“ H CF“ T H 0,. J. ‘F r’ = 6'i//,~‘r"‘//““‘~*”A\\‘~J:3Z‘ “ Ni" P-C-CFSeZ -. - Creep Time 4 Hr. ° % . . 1 . . . : 0 1 2 3 4 5 6 7 8 0.40 0. 50 c ' in Kg/cnz 0.40 30 c ' in Kg/cmz ¢’ in Degrees 4)’ in Degrees 3:.” 4; ..L H OT I _, r-l /’ 14>: 9.0 ml. 0:- fllqu— ‘- NT F-C-CFS-3 Creep Time 24 Hr. o : : 4 : : : 5 O 1 --2 3 4 5 6 8 Strain in z z" o... H I I ¢= 12.2 ¢ 04:- 5"- H fly- 1. 0.. Q". C'7 N“ F-C-CPS-l Creep Tine 120 Hr. ‘9 § : : % I. : : 0 1 2 3 4 5 6 8 Strain in 2 FIGURE 17 CONTINUED ' 0155 0.35 0.45 c ' in Kg/cmz' 0.45 c' in Kg/cmz' 0.55 0.35 31 32 1! RESULTS Table 4 sumarizes the results for the Creep-CPS tests under a creep load of 01:75 kilogram per square centimeter. (Specimens numbered C-C-CFS-l and C-C-CPS-S to 6). The friction angle at the end of all the creep periods was zero or nearly zero. This indicated that the entire creep load was resisted by the cohesive comonent of resistance with no stress transfer to the frictional component. A typical stress-strain curve for such a Creep-CFS test is shown in Figure 21. A curve of friction and cohesion versus axial strain is also plotted ”in Figure 21. These curves clearly show a value of zero for friction at the end of creep. From the results of the CPS test (Figure 22) it was noted at (Q3 - 0;) equal to 0.75 kilogram per square centimeter the two stress-strain curves are coincident, indicating a cohesive resistance only. Frictional resistance exists only if the two curves with different ( fi. )8 yield different strengths. Hence, a larger creep load was tried. It was decided to choose a creep load larger than the ( Q" - “3) value at which the two stress-strain curves in a CPS test separate. Examination of Figure 22 and Figure 23 led to the choice of a creep load of 1.00 kilogram per square centimeter for the compacted specimens and 1.15 kilograms per square centimeter for the consolidated specimens. Examination ”of the values of c' and ¢ ' from the Creep-CFS tests in Table 4 indicates ¢' for the compacted clay increased from 1.0 degree to 7.4 degrees with increasing time of creep. (Specimen numbers C-C-CFS-7 to 11) However, c' did not drop to zero but 33 dropped to a shear stress of 0.35 kilogram per square centimeter. This was slightly below the shear stress at which the two stress- strain curves in Figure 22 started to separate. The value of w' for the consolidated clay increased from 0.4 degree to 12.4 degrees with increasing time of creep. As before, c' did not drop to zero but to a shear stress of 0.37 kilogram per square centimeter. This shear stress was slightly below the shear stress at which the two stress-strain curves in Figure 23 separated. It was evident from this observation that the Kelvin model described creep only after the creep load exceeded some constant value of cohesive resistance. The writer has called this value of . cohesive resistance the threshold shear stress and denoted it as (G- . WT was taken as 0.35 kilogram per square centimeter for the compacted clay and 0.37 kilogram per square centimeter for the consolidated clay. The threshold values are shown in Figure 18 and Figure 19. Calculations for q1p and c‘ are presented in the Appendix. Figure 18 and Figure 19 show stress transfer curves for the compacted clay and the consolidated clay. The two curves in each' figure are the stress transfer curves calculated from the creep curves shown in Figures 14 and 15 and measured from the Creep-CFS tests. If the friction and cohesion actually behaved as the viscous and elastic elements of the Kelvin rheological model the two curves should be the same. The shear stress transfer from a viscous or cohesive resistance to an elastic or frictional resistance is clearly shown. Both types 34 of clay exhibited a stress transfer behavior similar to that of the Kelvin model above the threshold shear stress‘T} . The numerical values computed for the two types of specimen used agree only approxi- mately. For the compacted clay (Figure 18) the agreement is poor at shortdtime intervals (less than 700 minutes). In this time range values of 45' measured from the Creep-CFS tests are lower than those computed from the Creep test. Conversely, the values of c' are higher. For the consolidated clay (Figure 19) the agreement is poor at long-time intervals (longer than 1500 minutes). In this time range values of Q' measured from the Creep-CFS tests are also lower than those computed from the Creep test. Conversely, the values of c' are also higher. In spite of these differences the shape of the stress transfer curves measured from the Creep-CFS tests and computed from the Creep tests are similar. The choice of ‘T-y affects the values computed from the Creep tests. Since this value is chosen somewhat arbitrarily it could account for the differences. Another possible explanation for the differences could be variation of G as creep progresses. 35 gala/Bx I1]: #11) OZ'O OI'O 08'0 #30 8.93830 mom «Human. mwgmf w." 5593 39:5: 5 05:. macho oo.mm ocmfl comm ocmN coma “may moose all I ll. amen. whormoowoolllc .c some moouqulla u 38. 98.3851 . “Bowen C‘IHII‘IIIII‘IIIIII oi'o oz‘o os‘o ov‘e 09'0 Zia/8x u; ,o 36 ains/Bx u}: ch), 0 1'0 OZ'O 09'0 :8 5.5.28sz «.8 mummies mmmfim . 3 58: 8.3 8.3 8.3 8.3 moouo ell I .53 98.898 HT». moouo 4| I ll «8s. $0.320 Tllla .o ecmwoq 8.? 8m... r F 8.3 0130 09'0 OZ‘O zm:>/3)[ u]: ,3 09‘0 09‘0_ 37 1 CONCLUSIONS 5.1 Validity of Kelvin Model 5.2 The conclusions drawn here apply to the two types of clays tested. 1. Creep in a saturated clay may be represented approximately by the Kelvin model. 2. The clay behavior is such that stress is transferred from the component of cohesive resistance to the component of frictional resistance. This takes place only when the creep load exceeds a threshold shear stress. 3.- The component of frictional resistance increases from zero and approaches its ultimate value after long-creep times. The component of cohesive resistance drops to the threshold shear stress after long-creep times. Suggestions for Future Study 1. Clays of different mineral contents should be tested as described in this thesis to establish the general usefulness of the procedure. 2. A study should be made to find a simple rheologic model that will describe creep in a saturated clay to a closer approxi- mation than the Kelvin model. 3. The threshold shear stress should be investigated. 38 ‘11. BIBLIOGRAPHY Bea, R. 0. "Discussion of Friction and Cohesion of Saturated Clays," pp. 268-77. Journal Lf the Soil Mechanics and Foundations Division, vol. 89, SM 1. Ann Arbor: American Society of Engineers, 1963. Bishop, Alan W., and D. J. Henkel. The Triaxial Test. Second Edition. London: Edward Arnold Ltd., 1962. Buisman, A. S. Keverling. "Results of Long Duration Settlement Tests," pp. 103-06. Proceedings_ of the International COnference Ln Soil Mechanics and Foun ation Engineering, vol. 1. Cambri idge: 1936. Casagrande, A. and S. D. Wilson. "Effect Of Rate of Loading on the Strength of Clays and Shales at Constant Water Content," p. 251 Geotechnique, vol. 2. 1950. Dillon, Howard 8. "Structure and Identification of Clay Soils." Unpublished laboratory report, Soil Science 945, Michigan State University, East Lansing, 1963. Geuze, E. C .W .A. "Compression, an Important Factor in the Shearing Test," pp. 141-42. Proceedings_ Of'the Second International Conference Ln Soil.Mechanics and Foundation Engineering, vol. 3. Rotterdam: 1948. Geuze, E. C .W .A. Introduction by General Reporter for Session 2, pp. 119-21. Proceedings Lf the Third International Conference Ln Soil Mechanics and Foundation_ Engineering, vol. 3. Switzerland: 195 . Geuze, E.C.W.A. and T. K. Tan. "The Mechanical Behavior of Clays," Rheology, Ed. V. G. W. Harrison. New York: Academic Press Inc., 1954. Haefeli, R. "Creep Problems in Soils, Snow and Ice," pp. 238-50. Proceedin s of 323 Third International Conference g£_Soil Mechanics Egngoundation Engineering, vol. 3. Switzerland: 1953. Murayama, S. and T. Shibata.. "Rheological Properties of Clays," pp. 269-73. Proceedings_ of the Fifth International Conference Ln Soil Mechanics and Foundation Engineering, vol. 1. Paris: 1961. Rowe, P. W. "Ce=0 Hypothesis for Normally Leaded Clays at Equilibrium," pp. 189-92. Proceedings Lf the Fourth International Conference Ln Soil Mechanics and Foundation Engineering, vol. 1. London: 1957. 39 Schiffman, R. L. "The Use of Visco-Elastic Stress-Strain Laws in Soil.Testing," pp. 131-55. ASTM Special Technical Publication ' No. 254. Philadelphia: American Society for Testing Materials, 1959. Schmertmann, John H. and Jorj O. Osterberg. "An Experimental Study of the Development of Cohesion and Friction with Axial Strain in Saturated Cohesive Soils," pp. 643-94. Research Conference Ln Shear Strm mgth_ of Cohesive Soils. Ann Arbor: American Society 0 Civil Engineers, 1960. ' Terzaghi, Karl. Discussion of "Earth Pressure, Retaining Walls, Tunnels and Shafts in Sbils," pp. 205-06. Proceedings_ of thg_ Third International Conference Ln Soil Mechanics an Foundation Engineering, vol. 3. Switzerland: 1953. Vialov, S. S. and A. M. Skibitsky. "Rheological Processes in Frozen Soils and Dense Clays," pp. 12-24. Proceedings gflthg_Fourth International Conference on Soil Mechanics and Foundation E? ineerin , vol. 1. London: 1957. Vialov, S. S. and A. M. Skibitsky. "Problems of the Rheology of Soils," pp. 387-91. Proceedings_ of the Fifth International Conference Ln Soil Mechanics and Foundation Engineering, vol. 1. Paris: 1961. Wu, T. H., A. G. Douglas, and R. D. Goughnour. "Friction and Cohesion of Saturated Clays," pp. 1-23. Journal Lf the Soil Mechanics gnd_Foundations Division, vol. 88 SM 3. _Ann —Arbor: American Society of Civil Engineers, 1962. 21.1. APPENDIX 7.1 Derivation of Data Table for CPS Test 40 q’ 749’. K K A XZ-X‘,/r AL— c‘ ”' “‘\ d E \ f3 «a f ‘ \ ? >2“ /7” ’L \\ 7.: ,E >'_. @fizr“ \ ‘ D '\ Jlkfi' ‘o 'c'! ’2 fl \ \\ Q: /// I A \\ é \‘ g: 4%.: / I, I I ‘ 0"" >’ / I L A \ B I 7 * q- * * «5L V5“ f V”. fl “H .L z mafia/aq J X-EK"*%)H FIGURE '2'0 - man's CIRCLE FOR CFS AB=CD and AC=BD ta“ °‘ " “=4“ )/(Xz -X. ) 8‘“ 4’" “=4" ”(XE-X.) tan d = sin q; ¢ = 811;. (Y; ~Y‘ )/(x1_x‘ ) z = ¢'/tanq>' and z =a/tano< c' cos 45' c' = a/cos q), TEST DATA TABLE 7.2 Typical Data for Taste Run (See following tables and figures) 41 .0; o o 5. H 8 9 "2,. a 00" ' o I no a " no cue: 5‘ .5 ‘01? .5 v ":5 9+- “ 7. ’ ‘0 ° r-% i: ‘w % t 6 0 1.0 " 2.0 3.0 4.0 5.0 6.0 Strain in X o d) and c' Versus Strain 4.. ‘1‘. H “L H a o ' 8 A" \ #2" on .5 51.1 A? 9' oh - l o 6' v 1: b er ‘1. o o ; : ; : : s : 0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Strain in X FIGURE 21 - TYPICAL STRESS-STRAIH CURVE FOR COMPACTED ‘ CLAY CREEP-CPS TEST (C-C-CPS-é) ’ 42 TABLE 6 - GENERAL DATA SHEET Date 3/21/63 Test C-CFS-l Operator Holliday Cell 4 Sample C 16 TRIMMINGS Container No. 41 Cont. Wt. & Dry Wt. 59.27 Cont. Wt. 29.47 (grams) Water Wt. 11.85 Cont. Wt. & Wet Wt. 71.12 Dry Wt. 29.80 Water Content 39.8% SPECIMEN Length 3.00 in = 7.62 cm Volume 76.2 cm3 Area 10.0 cm2 Initial Final Wt. of Spec. 137.73 127.10 Dry Wt. of Spec. 96.28 96.28 Wt. of Water 41.45 30.82 Water Content. 43.0% 32.1% 43 TABLE 7- CONSOLIDATION DATA SHEET Cell 4 Test C-CFS-l AV = 10.0 cm3 v=vo -AV = 66.2 cm3 L=Lo(V/Vo) = 2.82 in A=Ao(V/Vo) = 9.11 cm‘ Chamber Pressure 2.00 Kg/cmz Back Pressure 1.5 Kg/cfi? Date Time Elapsed Burette Drainage WTime (Min. cc cc 3/21/63 1606 0.0 0.0 0.0 0.25 1.5 1.5 0.50 1.8 1.8 1.00 2.0 2.0 2.00 2.4 2.4 5.0 3.2 3.2 10.0 4.2 4.2 23.0 6.2 6.2 30.0 6.9---0.0 6.9 60.0 2.4 9.3 136.0 4.8---0.0 11.7 2108 302.0 1.2 12.9 3/22/63 0842 996.0 1.2 12.9 1502 1356.0 1.3 13.0 1621 1455.0 1.3 13.0 1634 Back Pressure Applied Cell 4 TABLE 8 - CPS DATA SHEET Chamber Pressure 3.5 Kg/cm? Proving Ring Number 684 Proving Ring Constant. 0.1470 Kg/div. ** ( q}..q3) = Elgggl-(l-E) = !%%%%2(1-Q) Time 0915 0930 0940 0946 0949 0953 1008 1012 1016 1021 1042 1050 1119 1125 1139 1148 1220 1228 Load Dial N x 10" 0.0600 .0630 .0646. .0653 .0655 .0656 .0661 .0661 .0662 .0662 .0664 .0664 .0640 .0650 .0660 .0669 .0667 .0667 Strain Dial in. 0.0 0.0028 .0056 .0071 .0085 .0099 .0155 .0169 .0183 .0197 .0282 .0310 .0424 .0451 .0508 .0536 .0649 .0676 Strain .% 0.0 0.1 .25 .30 .35 1.00 1.1 1.5 1.6 1.8 1.9 2.3 2.4 ( 91‘ Q3) Kg/cm‘ 0.0 0.484 .742 . .854 .889 .902 .930 .980 9.994 .994 1.025 1.03 1.03 1.035 1.05 1.09 1.065 1.055 Test C-CI-‘S -1 Date 3/25/63 g Wt. Added g Wt. Removed _ Constant D. u— Pressure ( q.‘ -' Q3) C811 Kg/cm‘ Kg/cmz 0.0 1.5 0.484 1.5 .742 1.5 t .854 1.75 .889 1.75 .902 1.75 *4 .980 1.50 .980 1.50 e .994 1.75 .994 I 1.75 to ‘ 1.025 1.50 1.03 1.50 e 1.03 1.75 1.035 1.75 *4 1.05 1.5 1.09 1.5 t 1.065 1.75 1.055 1.75- 45 TABLE 8 CONTINUED Cell 4 Test C-CFS-l Time Load Strain Strain ( V. - W3) A u= 19:22:32: Dial 0151 cr. - 03) Cell N x 10" in. % Kg/cm‘ Kg/cm" Kg/cmz 1300 .0673 .0790 2.8 1.14 1.14 **1.50 1308 .0674 .0817 2.9 1.155 1.155 * 1.50 1321 .0673 .0874 3.1 1.14 1.14 1.75 1327 .0673 .0904 3.2 1.14 1.14 **1.75 1343 .0677 .0959 3.4 1.20 1.20 1.50 1347 .0677 .0986 3.5 1.20 1.20 * 1.50 1413 .0676 .1071 3.8 1.18 1.18 1.75 1419 .0676 .1100 3.9 1.85 1.85 **1.75 1445 .0681 .119 4.2 1.25 1.25 1.50 1451 .0682 .121 4.3 1.26 1.26 * 1.50 1508 .0680 .127 4.5 1.23 1.23 1.75 1515 .0679 .130 4.6 1.22 1.22 ..1'75 1537 .0684 .138 4.9 1.30 1.30 1.50 1544 .0685 .141 5.0 1.31 1.31 * 1.50 1600 .0683 .147 5.2 1.27 1.27 1.75 1608 .0683 .149 5.3 1.27 1.27 **l.75 1634 .0688 .158 5.6 1.34 1.34 1.50 1637 1.0689 .161 5.7 1.35 1.35 * 1.50 1741 .0689 .1861 6.6 1.35 1.35 1.75 1749 .0689 .1890 6.7 1.34 1.34 **1.75 1805 .0692 .194 6.9 1.39 1.39 1.50 46 TABLE 8 CONTINUED Cell 4 Test C-CP's-1 Time 1153: 83:31: Strain ( Cf. - V3) 023:9.) 19:23:33 N x 1074 in 75 Kg/cmz Kg/cmz Kg/cmz‘ 1812 .0692 .197 7.0 1.39 1.39 * 1.50 1824 .0690 .203 7.2 1.35 1.35 1.75 1830 .0690 .205 7.3 1.35 1.35 **1.75 1846 .0693 .2110 7.5 1.39 1.39 1.5 1853 .0695 .2138 7.6 1.41 1.41 * 1.5 1908 .0692 .220 7.8 1.37 1.37 1.75 1916 .0691 .222 7.9 1.35 1.35 1“1.75 1930 .0695 .2285 8.1 1.41 1.41 1.50 1938 .0697 .231 8.2 1.42 1.42 1.50 47 wmm. sum. Hum. oom. m¢¢. 05¢. omv. omw. w¢v. wmfi. N¢¢. oNv. bmv. vmw. amw. va. wm¢.o «3me 030 u «an. mmva. 5w.> Homa. can. mum. cued. vw.h fiend. can. ham. mbva. ¢m.h Homa. cum. mom. mo3H. 3m.b Homa. can. oww. cama. #m.> Head. cam. «54. @mmfl. «w.b Homa. can. mmw. omma. 3m.u Head. can. mm¢. omma. vm.b Hana. cum. mwv. noma. om.o caaa. mum. cmw. mmoa. oa.¢ onwo. emu. ovv. owed. no.5 chmo. omm. «~3. Hooa. oo.v onwo. emu. omv. .oouo. uw.m o3oc. mun. mmw. . ammo. om.u bawo. own. wmw. ammo. .om.~ have. o3u. ha¢. «mmo. om.n 5H3o. o¢n. wmv.o mouo.o 5H.H vouc.o m¢~.o . ............m0...r owg &£—w -6. 3.33» .68 . .... .373 1.3%.? . 5:3 Hammouo “umma omo. one. omc. omo. one. one. omo. omc. mac. ONO. One. ouc. mac. Odo. OHo. 6H6. mooJo Fm» 33% 3 .3 4. hmu=o H030; _os~.a oom.H mom.H mHm.H cmm.d m¢m.a oom.H owm.H co¢.H ouv.d mmv.H omv.H. Oh¢.H mw¢.H 0cm.H cum.H .mmm.H ~x 3-3 3 tan can. mm. ooh. co. mac. Ho. mac. no. one. co. mmo. ow. 03o. up. one. on. coo. on. cam. «w. mom. um. omm. ca. 0mm. .vo. mam. 53. com. oo. H cmw. ¢c. H mov.o uo.a n» 3.61 .3. ooéu w o>nnu no a: a. .5 X 0 O O O O O Flr1oyeaaaaac§c>c>c>64r464 @ch r-ICOO‘O‘) O ‘0 5° 4} :: Himmolm NNCOV‘V‘ HHHHHHHHHHHH 00m. 03m. 30m. ANN. 000. 30N. 00H. 00H. 00H. 55H. 55H. 35H. HOH. 30H. 0300. 0000. 5H30. 3000.0 .003.0 “063 8:69 “paws 003. 003. 003. 003. 0H3. 0H3. 003. 003. HN3. 003. 003. 003. 003. 033. 0031 503. 003. .x -NX 00H. 000. 000. 000. 000. 000. 000. 000. 050. 050. 050. 350. 000. 000. 030. N00. 000. 0H0.0 F...» 03N.H 03N.H 03N.H 03N.H 00N.H 00N.H 00N.a 00N.H 05N.H 00N.H 00N.H ~00.H NHO.H 0N0.H N30.H 000.H 000.H. 003.H .x .0 qagaw_qaaaw. 56 005. 005. 005. 005. 005. 035. 035. 005. 005. 0N5. 0H5. 500. 500. 050. 500. 000. 000. 050.0 666.6 06. QfiauHQSA 003. 003. 003. 003. 000. 0H0. 000. 000. .000. 000. 000. 000. 000. 000. 000. 005. 005. 000.0 #53050 90¢: 0.00 I 0H 30¢“. 6H6.H 6am.H 6am.a 6Hm.a 666.H 66¢.H 666.3 666.3 6m6.a 66¢.H 666.3 666.H m66.a 6m6.H mH6.H 666.H 6H~.H 6ea.H ~x 3.5 3+.an 030.H 030.H 000.H 300.H 000.H 050.H 000.H 000.H 000.H 005.H 0H5.H 0N5.H 035.H 055.H 000.H 000.H 050.H 000.H 6mm. 668. 6mm. 66». own. 666. m66. 666. 666. 666. 666. 666. 666. 666. 6H6. 666. 66». 666. 666. 6H6. m66. 666. H66. 6m6. 666. m66. 666. 666.6 666. 663.3 moo. 66H.H 666. 6m~.H 663.6 636.H Jr u 0.9.60 ._. mew 66m." 0 .5 o>nso H0000 6:; 6.6 005.H 0.0 62.4 6.6 H664 26 666; 6.5 000.H 0.0 6364 6.6 0N0.H 0.0 000.H 0.0 000.H 0.3 634 6.6. 030.H 0.0 304 6:6 63; mé 6634 oé 000.H 04H 634 64 66H.H 0.6 57.3 % urexzs 54. saaxfiaq u; A) a 5 52% 0.0 0.0 0.5 0.0 0.0 0.3 0.0 0." 01—” 0 0 0 4 . 4 u u u a u mh "a... 0 "7.. 0 0 :V O 9.. I 0‘ I. u 8 X 0 gr .0 Lino fl 0 9 3 at T. .0.. 0 TL 0 v... .9 . 0 .l .I \Ilulux\\.} \ fl. -\ coA oollI‘nlllulllillllo T. 09L! 0 H1900...“— ammn. mom 9550 Egmlmmmmaw I mm 550?.“ x 5 53% onea ona ow» cub one cum cuw * + 3.. .9.“ and , O Z'O 0L 1'. 9 I__ GET 1119/BX U]: (53,-- ‘13) 3‘1 1' VI 9‘I 8‘1 55 TABLE 14 - GENERAL DATA SHEET Date 4/20/63 Operator Holliday Sample C 7 TRIMHINCS Container No. 211 Cont. Wt. 20.34 (grams) Cont. Wt. & Wet Wt. 46.92 SPECIMEN Length 3.00 in I 7.62 on Area 10.0 on} Initial Wt. of Spec. 137.80 ny Ht. of Spec. 97.69 Ht. of Water 40.11 Water Content 41.2% Test C-C-7 & C-C-CFS-7 Cell 1 Cont. Wt. & Dry Wt. 39.37 Water Wt. 7.55 Dry Wt. 19.03 Water Content 39.8% Volume 76.2 cm? Final 129.15 97.69 31.46 32.2% Cell 1 AV =- 12.6 cm! Chamber Pressure 2.00 Kg/cmt Date 4/20/63 4/21/63 TABLE 15 - CONSOLIDATION DATA SHEET Time 1014 1214 1414 1714 1035 1040 56 Test c-c-7 s. C-C-CFS-7 v=vo - AV a 63.6 cm3 A=Ao(V/Vo) ' 8.87 cm? Elapsed Burette Time Min. cc 0.0 10.0 .25 8.2 .5 8.0 1.0 7.7 2.0 7.3 5.0 6.4 13.0 5.0 15.0 4.6 30.0 2.8--10.0 60.0 7.5 120.0 5.1---10.0 240.0 8.6 420.0 8.1 1461.0 7.6 Back.Pressure Applied Back Pressure 1.5 Kg/cm? Drainage cc 0.0 1.8 2.0 2.3 2.7 3.6 5.0 5.4 7.2 9.7 12.1 13.4 14.0 14.5 If .;. 57 TABLE 16 - CREEP DATA SHEET Cell 1 Chamber Pressure 3.5 Kg/cmf Dead Load 8.87‘Kg Date Elapsed Time Min. 4/22/63 0.0 .25 .5 1.0 2.0 5.0 10.0 15.0 30.0 60.0 120.0 240.0 480.0 840.0 4/23/63 1440.0 avvwfiv 1740.0 4/24/63 2940.0 3240.0 4/25/63 4320.0 Strain Dial in. 0.0230 .0255 .0265 .0275 .0290 .0320 .0351 .0378 .0421 .0481 .0525 .0559 .0585 .0602 .0610 .0615 .0624 .0629 .0630 Test C-C-7 & C-C-CPS-7 Back Pressure 1.5 Kg/cIF (G}- 93) 1.00 Kg/cn‘ Strain Pore Pressure % Kg/ c1 0.0 1.52 .083 .124 1.90 .159 1.95 .212 2.00 .248 2.08 .427 2.12 .524 2.18 .675 2.25 .886 2.30 1.081 2.35 1.165 2.40 1.259 2.41 1.318 2.47 1.345 2.55 1.361 2.60 1.394 2.74 1.415 2.70 1.417 2.86 ‘1? ‘r ~7 ja3'". . Cell 1 TABLE 17 - CFS DATA SHEET Chamber Pressure 3.5 Kg/cm2 Proving Ring Number 3144 Proving Ring Constant 0.0455 Kg/div. (0'. " Q’s) _N:RC 196.) = Time 0853 0915 0920 0951 0955 1025 1028 1120 1152 1153 1222 1226 1250 1255 1326 1332 1357 Load Dial N x 10-4 0.0100 .0147 .0149 .0169 .0170 .0139 .0138 .0159 .0160 .0143 .0143 .0163 .0165 .0149 .0148 .0168 .0172 .0156 Strain Dial in. 0.040 Strain .% 1.417 1.451 1.486 1.735 1.770 2.265 2.300 2.760 2.795 3.255 3.290 3.675 3.745 4.160 4.230 4.65 4.72 5.20 58 Test C-C—7 & C-C-CFS-7 Date 4/25/63 *1.Kg Wt. added **1.Kg Wt. added N(.0455)( _ .87 1.6) (‘L - 9%) Kg/cmF 1.00 1.242 1.250 1.348 1.353 1.195 1.191 1.295 1.302 1.216 1.216 1.310 1.320 1.240 1.235 1.332 1.352 1.272 £5u=\- (qt "' W3) Kg/cmz 0.0 .242 .250 .348 .353 .195 .191 .295 .302 .216 .216 .310 .320 .240 .235 .332 .352 O 272 Constant Pressure Cell Kg/cm? 2.86 2.86 2.86 it 2.36 2.36 a 2.86 2.86 9* 2.36 2.36 t 2.86 .2.86 4* 2.36 2.36 a 2.86 2.86 *4 2.36 2.36 a 2.86 Cell 1 Time 1406 1446 1453 1520 1526 1603 1614 1641 1645 Load Dial N x 10‘4 .0153 .0181 .0184 .0161 .0159 .0185 .0188 .0163 .0162 Strain Dial 1n. .153 .167 .170 .187 .190 .204 .206 .223 .226 TABLE 17 CONTINUED Strain .% 5.4 5.9 6.0 6.6 6.7 7.2 7.3 7.9 8.0 59 Test C-C-7 & C—C-CFS-7 ( q,-q3) Kg/cm‘ 1.258 1.391 1.405 1.288 1.284 1.405 1.415 1.298 1.296 bsu=|' ( ¢;- V5) Kg/cm‘ .258 .391 .405 .288 .284 .405 .415 .298 .296 Constant Pressure Cell Kg/cm1 .2.86 at 2.36 2.36 a 2.86 2.86 *4 2.36 2.36 * 2.86 2.86 60 666._ 000. 003. 303. 003. 000. 000. 300. N00. 003. 003.. 303. 053.0 uao\0¥ .0 \ 000. 303. 003. 553. 303. 003. 300. 000. 003. 003. 533. 033. 053.0 6 moo.o “d“ 6562.; 665. 665. 665. 665. 665. 655. 655. 655. 555. 655. 665. 565. 03H.0 0.. O O O .0 0000550000 NV‘Q‘HFO‘OIDQ' 80005040036100 00.0 35.0 0H.0 .000 .gzduyx .0 03H. 03H. 00H. 50H. 00H. 30H. 0HH. NHH. 00H. HHH. 33H. 00H. N3H.0 06:.» ” XCdp 5-666.6.6. ”5665 503. 003. 303. 330. 033. 333. 003. 003. 003. 003. 003. .666. 003.0 .X'NX 3006 000. 000. 000. 000. 000. H00. 030. 530. 030.. 000. 000. 000.0 cqm> 666. 666. 666. 566. 666. 666. 666.5 666. 666. 666.5 666. 656. 656.5 666. 666. 656.5 656. 566. 656.5 656. 566. 656.5 656. 656. 666.5 656. 656. 666.5 666. 566. 566.5 566. 666. 666.5 666. 666. 656.5 656.6 656.6 .x .5 3.605.. 66.50 66 666.5 u_6 0>550 mason 000.H 0002H 00N.H 05N.H 00N.H 03N.H. 000.H 000.H 0NN.H 00N.H 00H.H HHN.H 000.H 65 @756 5.6.55 #05050 35¢: .000 I 0.." and“. 566.5 566.5 666.5 666.5 666.5 666.5 656.5 656.5 666.5 666.5 666.5 666.5 666.5 665.. 655. 665. 655. 665. 655. 665. 665. 666. 665. 666. 665. 656. 666. 666. 656. 566. 656. 666. 666. 666. 656. 556. 665» 556.6 665.6 0» 31.60 66 665.5 "”6 «>550 50000 556.5 656.5 556.5 66665 666.5 666.5 666.5 656.5 656.5 666.5 656.5 566.5 666.5 3-6 ID 6 In %' “$9118 r~cau0cau0c>uac>u>c>uac>ca 64cwcwcocoi3-3Innn~o~0t~t~ - (rs) in Kg/cm‘ (W. 61 1.6 1.2 1.4 N 1.0 0.8 <- 0.2 1 L I o 1.0 2.0 310 [.0 5:0 6.0 720 870 Strain in% FIGURE 24 4 STRESS-STRAIN CURVE FOR C-C-CPS-7 62 TABLE 19 - GENERAL DATA SHEET Date 5/20/63 Operator Holliday Sample F l TRIMHINGS Container No. 211 Cont. Wt. 20.34 (grams) Cont. Wt. & Wet Wt. 57.09 SPECIMEN Length 3.00 in = 7.62 cm Area 10.0 cm2 Initial Wt. of Spec. 135.41 Dry Wt. of Spec. 89.77 Wt. of Water 45.64 Water Content 50.9% Test P-C-l & P-C-CPS-l Cell 1 Cont. Wt. & Dry Wt. 45.34 Water Wt. 11.75 Dry Wt. 25.00 Water Content 47.0% Volume 76 .2 663 Final 120.02 89.77 30.25 33.0% Cell 1 AV = 18.6 663 TABLE 20 - CONSOLIDATION DATA SHEET Chanber Pressure 2.00‘Kg/cmz Date 5/20/63 5/21/63 Time 0949 1349 1549 2049 0749 0949 0955 Elapsed Time Min. 0.0 .25 .50 1.0 2.0 6.0 10.0 15.0 30.0 60.0 80.0 132.0 240.0 360.0 660.0 1320.0 1440.0 Burette cc 10.0 8.8 8.6 8.4 7.8 6.5 5.7 4.3---10.0 7.3 3.1 1.2--10.0 7.5 6.1 5.5--10.0 9.5 9.2 9.2 Back.Pressure Applied 63 Test F-C-l & P-C-CPS-l V=Vo - AV II 57.6 cm5 AIAO(V/Vo) - 8.31 cm2 Back Pressure 1.5 Kg/cmF Drainage cc 0.0 1.2 1.4 1.6 2.2 3.5 4.3 5.7 8.4 12.6 14.5 17.0 18.4 19.0 19.5 19.8 19.8 64 TABLE 21 - CREEP DATA SHEET Test P-Cv-l & P-C-CPS-l Back.Pressure 1.5 Kg/cm? (0" - 03) 1.15 Kg/cn‘ Cell 1 Chamber Pressure 3.5 Kg/cmz Dead Load 9.56 Kg Date EIApsed Strain Strain Pore Tine Dial , Pressure Min . in . % Kg/cm" 5/22/63 0.0 0.008 0.0 1.60 .25 .029 .770 .50 .031 .825 2.20 1.0 .032 .886 2.23 ' 3.0 .035 .986 2.27 5.0 .038 1.110 2.32 10.0 .045 1.364 2.39 15.0 .048 1.450 2.41 30.0 .055 1.705 2.50 60.0 .063 1.995 2.52 120.0 . .070 2.260 2.59 240.0 .077 2.540 2.62 360.0 .081 2.677 2.69 480.0 .083 2.755 2.70 756.0 .087 2.890 2.76 5/23/63 1440.0 .090 3.010. 2.85 1680.0 .092 3.074 2.88 1920.0 .093 3.120 2.89 2160.0 .094 3.150 2.89 TABLE 21 CONTINUED Cell 1 Test P-C-l 8 P-C-CPS-l A Date Elapsed Strain Strain Pore Tine Dial Pressure Win. in. ‘ % Kg/cn" 5/24/63 2880.0 .096 =3.220 2.92 3120.0 .097 3.270 2.98 3360.0 .099 3.325 2.99 3600.0 .100 3.350 2.99 5/25/63 4320.0 .102 3.440 3.00 4560.0 .103 ' 3.490 3.03 4800.0 .105 3.550 3.05 5/26/63 5760.0 .109 3.700 3.10 6600.0 .111- 3.760 3.10 5/27/63 7200.0 .118 4.01' 3.11 66 TABLE 22 - CFS DATA SHEET Test P-C-l I. P-C-CPS-l Date 5/27/63 *1 Kg Wt. Added Cell 1 Chamber Pressure 3.5 Kg/cm” Proving Ring Nunber 3144 Proving Ring Constant 0.0455 Kg/div. (v. - v.) - "-L—HRC 1-0 = "L—Rg‘f‘gis l-e) **1Kg Wt. Removed Time Load Strain Strain ( (I. - 0’3) A u=L|57 3:22:32: Dial Dial G}-WS) 0611 N x 10""r in. % Kg/cm" Kg/cm‘ Kg/cnlz 0815 0.0100 0.109 4.01 1.150 0.0 3.11 0841 .0125 .112 4.11 1.281 .131 3.11 0843 .0125 .113 4.14 1.281 .131 3.11 0845 .0125 .114 4.175 1.281 .131 1“3.11 0928 .0147 .127 4.64 1.398 .248 2.61 0931 .0148 .128' 4.68 1.400 .250 * 2.61 1007 .0114 .145 5.30 1.223 .073 3.11 1009 .0114 6.146 5.33 1.222 .072 ”3.11 1150 .0152 .180 6.59 1.416 .266 2.61 1152 .0152 .181 6.63 1.416 .266 2.61 1155 .0152 .182 6.66 1.416 .266 * 2.61 1318 .0116 .219 8.02 1.231 .081 3.11 1320 .0116 .220 8.06 1.228 .078 **3.11 1420 .0150 .240 8.77 1.400 .250 2.61 1422 .0151 .241 8.80 1.405 .255 * 2.61 1448 .0118 .254 9.30 1.242 .092 3.11 1454 .0117 .256" 9.40 1.234 .084 3.11 1500 .0117 .259 9.50 1.232 .082 3.11 67 qu. mm¢. nod. and. adv. 50H. wuv. maw. can. «N4. Haw. «cu. add. .wow. .oou. . «av. Had. «an. . mHvJ wow. ecu. hqu wov» eon. mac. maw. waH. un#. NN¢. mod... wm¢.o a¢¢.o owH.c «animu— uv moo . o .o . "Jon" Jvchnx 8:32..» sou. mfi~.. 6H“. can. mun. «nu. on". «as. «an. «an. mou.c .4... 23:9u «Ho. «#4. Has. oc¢. sow. was. 555. saw. «H4. ”H5. mav.o .Xst HimeIOIm “Hawk one. mac. aao. coo. Hao. woe. soc. Hao. mac. moo. mac.o c...» 3.5 w a. .5». wgm 3.2 $0 I 2 52.". was. mac. was. was. was. mH». sue. was. .6us. «as. was. was. «no. «as. «as. «as. was. «H6. uu5.. 5H6. .moa.o mmo.c .x .» can. can. can. Haw. NH». mam. mHn. can. man. now. omN.H omuna omnwa aNN.H7 aNN.H mNN.H mNN.H VNN.H mNN.H mmN.H on~.o chN.H my qa-;w SEA 0 H o>H=o Hosea. wmm.H mmm.H omm.H mmmsa mam.H www.H mam.H omm.H owm.H mmm.H oun.a aw+c&m Hos. use. Rush. was. «oh.. «no. men. one. men. one. as». use. was. one. «as. was. Hos. «no. mos. one. ous.o ooo.od A» Oswaaw mp ova.“ ”we o>uuo.uonmw. mo¢.H 9.0 mow.a m.» mc¢.H o.» oa¢.a m.p oa¢.a 6.6 NH¢.H man oa¢.H c.o mov.H m.m Ho¢.H on» oa¢.a m.w o¢¢.H ma.¢ aaeuuv v» “19118 - V3 ) in Kg/cn‘ (V. 68 “2 a" ‘1 H“ f’w— .— fi' ‘1 .1 fi—m F... ‘2 H. “2 c": ‘2 e. "1 0.. ‘3 o' 0 1. : : e f :4 4 : : : 1.0 2.0_ 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.9 Strain in% FIGURE 25 - STRESS-STRAIN CURVE FOR P-C-CPS-l 7.3 Calculations for T0 and c' for Compacted Clay a) Creep Test (C-C-7) 21c: u. . _ - /