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Stress-path independent behaviorr of cohesionless soil
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constant depends only on the interpartlcle friction angle and can be estimated from the latter and the stress ratio when the dilatsncy rate is zero. He also proposes a flow rule which is represented in ter~s of the rate of contraction and stress ratio. ~71 TATSUOKA, F Dilatency characteristics of soil.Discussion. SoILS FOUND.VIS, N2,1975, F73 -78 • The author studies the stress-dilatancy characteristics of soils in the three dimensional stress condition without rotation of the principal axes of stress, and the relation between undrained and drained deformational properties of saturated soils. Auth.
h72 FARMER, IW UNIV .DURHAM, GB Undrained strengths of chemically grouted soils. IF,2~,IOR. PROC.2ND II~T.CONGRESS IAEG, SAO PAULO,1974,PAP~R VI-I, V2,197~, 6P. This paper describes the results of a series of undrained triaxial tests c~ sand samples grouted with soft, medium and stiff chemical grouts. Compared with the untreated send, the effect of introducing soft gels into the porespace was to increase the cohesive strength and reduce the friction ~ l e effectively reducing the shear resistance of the soil at high cc~finin~ pressures. The effect of introducing stiff grouts was to increase both the cohesive strength end the friction angle. Auth.
Deformation characteristics See also abstracts: h62,572.
473 LADE, PV UNIV. CALIF., LOS ANGELES ,USA DUNCAN, JM UNIV .CALIF. , B ~ E L E Y , USA Stress-path indepemdent behaviour of cohesionless soil. 15F,32R. J. GEOTECH. ~ G N G DIV .ASCE,VI02, GTI, JAN., 1976, P51-68. The strains induced in cohesionless soil by changes in stress vary considerably depemdin~ On stress level (defined as a stress ratio), confining pressure and on whether the c h ~ e s in stress involve primsry loading~ unloading or reloading. Based on the results of triaxial tests it was found that except for the maximum previous stress level experiencedj the stress history has little influenceon the behaviour of cohesionless soil. However, for stresspaths involving unloading or reloadlng~ stress-path does have an influence on the strains, and the stresspath with the higher average stress level produces the larger strains. An elsstoplastic stress-strain theory was used to calculate the strains for the stress-paths Inves. tigated and generally good agreement between calculated and measured strains was obtained. It is shown that the plastic deformations in cohesiomless soil can be determined from the state of stress~ and the increment in total •~ork. Auth.
474 SKINNER, EH ET AL Biexial test results, Crescent Mine, Coeur dtalene mining district. 7F,6T,43R. APPLICATIONS OF ROCK MECHANICS,PROC.15TH SYMP.ROCK MECH.,SoUTH DAKOTA. ASCE, 1975, P2 27- 271. A series of tests has been carried out with the U.S.B.M. biaxlal test device on quartzite cores retrieved frc~ an overcore stress determination program. The authors present results of these biaxial tests, have investigated the biaxial obtained load-deformation curve s reviewed those results after computer ena/ysis and presentation in equation form representing 'test fit" curves, have used those results as a basis for predicting rock behaviour of the Revert quartzite as either characterizing linear of nonlinear bshaviour, and further suggest a
simple numeric and graphic method for using biaxial test data as test criteria for llnear/nonlineer elastic rock behavior in the form U/a = P/E as a constant slope line.
475 HUSTRULID, W HUSTRULID, A The CSM cell - a boreb~le device for determining the modulus of rigidity of rock. 4F,8T,8R. APPLICATIONS OF ROCK MECHANICS,PROC.15TH SYMP.ROCK MECH., SOUTH DAKOTA .ASCE, 1975, PI81- 225 • The design, calibration and use of the CSM cell, a borehole device for determining the modulus of rigidity of rock, is described. Field tests conducted at the Colony Oil Shale Mine at Rifle, Colorado, are presented in detail to demonstrate the application, the ease of operation and the reliability of the CSM cell system. The results are shown to be very reproduceable ~ d to agree well with those obtained using another more involved method. Applications for the device are discussed. h76 YOSHIKUNI, H NAKANODO, H Consolidation of a clay cylinder with external radial drainage. SoILS FOUND,VI5, Nl, 1975, PI7- 28. The compressibility and rate of consolidation are neces. sery parameters for settlement analysis, and they can be obtained by the triax~al consolidation test of a cylindrical sample with external radial flow of water. The rate of consolidation in this case is usually estimated by using Terza4~hi's consolidation equation, independent of the deformation of the sample. However, it is known from laboratory test results that the rate of consolidation depends upon the deformation condition. The authors study the process of consolidation of a clay cylinder with external radial drainage under four different conditions, as an application of a theory based on the concept of consolidation potential to the consolidation problem. 477 ISH IHARA 3K TATSUOKA, F YASUDA, S Undrained deformation and liquefaction of sand under cyclic stresses. SOILS FOUND, VI5,NI, 1975, P29- 45. Increasin~ awareness of the dangers caused by liquefac. tion of ssmdy ground during earthquakes has prompted research into the mechanism by which loss of strength occurs as a result of progressive develol0ment of pore !0ressuree within saturated sands. Previous studies on the deforms~ tion characteristics of sand disclosed four importent fundamental aspects; dilatency, shear strain, yield and 8xlisotrolmJ. In this paper the s~thors investigate a fifth aspect, the cc~%ditions specifying the onset of llquefac. ti(m, and using the results from !0revious studies proposed a model by which it is possible to assess the development of pore pressures and shear strains in an element of sand when it undergoes cyclic loading In undrained condltio~. The performances of sand predicted by this method proved relevant to the assessment of the likely occur~ice o_~ liquefactiom for wide ranges cf lomding conditions.
478 ISHIHARA, K YASL"DA,S ~d l~luefaetion i,n hollo,~ cylinder torsion under irr eg.,lar excitation. SOILS FOUND.VIS, NI,1975, P45- 59. The authors used torsion shear test apparatus to perform a number of liquefaction tests on h o l ~ cylindrical samples of saturated sand encased in a triaxial cell. With this equipment smy desired load time history could be applied to a speclm~. The authors were able to establish rel%tionships between the amplit~le of shear stress
constant depends only on the interpartlcle friction angle and can be estimated from the latter and the stress ratio when the dilatsncy rate is zero. He also proposes a flow rule which is represented in ter~s of the rate of contraction and stress ratio. ~71 TATSUOKA, F Dilatency characteristics of soil.Discussion. SoILS FOUND.VIS, N2,1975, F73 -78 • The author studies the stress-dilatancy characteristics of soils in the three dimensional stress condition without rotation of the principal axes of stress, and the relation between undrained and drained deformational properties of saturated soils. Auth.
h72 FARMER, IW UNIV .DURHAM, GB Undrained strengths of chemically grouted soils. IF,2~,IOR. PROC.2ND II~T.CONGRESS IAEG, SAO PAULO,1974,PAP~R VI-I, V2,197~, 6P. This paper describes the results of a series of undrained triaxial tests c~ sand samples grouted with soft, medium and stiff chemical grouts. Compared with the untreated send, the effect of introducing soft gels into the porespace was to increase the cohesive strength and reduce the friction ~ l e effectively reducing the shear resistance of the soil at high cc~finin~ pressures. The effect of introducing stiff grouts was to increase both the cohesive strength end the friction angle. Auth.
Deformation characteristics See also abstracts: h62,572.
473 LADE, PV UNIV. CALIF., LOS ANGELES ,USA DUNCAN, JM UNIV .CALIF. , B ~ E L E Y , USA Stress-path indepemdent behaviour of cohesionless soil. 15F,32R. J. GEOTECH. ~ G N G DIV .ASCE,VI02, GTI, JAN., 1976, P51-68. The strains induced in cohesionless soil by changes in stress vary considerably depemdin~ On stress level (defined as a stress ratio), confining pressure and on whether the c h ~ e s in stress involve primsry loading~ unloading or reloading. Based on the results of triaxial tests it was found that except for the maximum previous stress level experiencedj the stress history has little influenceon the behaviour of cohesionless soil. However, for stresspaths involving unloading or reloadlng~ stress-path does have an influence on the strains, and the stresspath with the higher average stress level produces the larger strains. An elsstoplastic stress-strain theory was used to calculate the strains for the stress-paths Inves. tigated and generally good agreement between calculated and measured strains was obtained. It is shown that the plastic deformations in cohesiomless soil can be determined from the state of stress~ and the increment in total •~ork. Auth.
474 SKINNER, EH ET AL Biexial test results, Crescent Mine, Coeur dtalene mining district. 7F,6T,43R. APPLICATIONS OF ROCK MECHANICS,PROC.15TH SYMP.ROCK MECH.,SoUTH DAKOTA. ASCE, 1975, P2 27- 271. A series of tests has been carried out with the U.S.B.M. biaxlal test device on quartzite cores retrieved frc~ an overcore stress determination program. The authors present results of these biaxial tests, have investigated the biaxial obtained load-deformation curve s reviewed those results after computer ena/ysis and presentation in equation form representing 'test fit" curves, have used those results as a basis for predicting rock behaviour of the Revert quartzite as either characterizing linear of nonlinear bshaviour, and further suggest a
simple numeric and graphic method for using biaxial test data as test criteria for llnear/nonlineer elastic rock behavior in the form U/a = P/E as a constant slope line.
475 HUSTRULID, W HUSTRULID, A The CSM cell - a boreb~le device for determining the modulus of rigidity of rock. 4F,8T,8R. APPLICATIONS OF ROCK MECHANICS,PROC.15TH SYMP.ROCK MECH., SOUTH DAKOTA .ASCE, 1975, PI81- 225 • The design, calibration and use of the CSM cell, a borehole device for determining the modulus of rigidity of rock, is described. Field tests conducted at the Colony Oil Shale Mine at Rifle, Colorado, are presented in detail to demonstrate the application, the ease of operation and the reliability of the CSM cell system. The results are shown to be very reproduceable ~ d to agree well with those obtained using another more involved method. Applications for the device are discussed. h76 YOSHIKUNI, H NAKANODO, H Consolidation of a clay cylinder with external radial drainage. SoILS FOUND,VI5, Nl, 1975, PI7- 28. The compressibility and rate of consolidation are neces. sery parameters for settlement analysis, and they can be obtained by the triax~al consolidation test of a cylindrical sample with external radial flow of water. The rate of consolidation in this case is usually estimated by using Terza4~hi's consolidation equation, independent of the deformation of the sample. However, it is known from laboratory test results that the rate of consolidation depends upon the deformation condition. The authors study the process of consolidation of a clay cylinder with external radial drainage under four different conditions, as an application of a theory based on the concept of consolidation potential to the consolidation problem. 477 ISH IHARA 3K TATSUOKA, F YASUDA, S Undrained deformation and liquefaction of sand under cyclic stresses. SOILS FOUND, VI5,NI, 1975, P29- 45. Increasin~ awareness of the dangers caused by liquefac. tion of ssmdy ground during earthquakes has prompted research into the mechanism by which loss of strength occurs as a result of progressive develol0ment of pore !0ressuree within saturated sands. Previous studies on the deforms~ tion characteristics of sand disclosed four importent fundamental aspects; dilatency, shear strain, yield and 8xlisotrolmJ. In this paper the s~thors investigate a fifth aspect, the cc~%ditions specifying the onset of llquefac. ti(m, and using the results from !0revious studies proposed a model by which it is possible to assess the development of pore pressures and shear strains in an element of sand when it undergoes cyclic loading In undrained condltio~. The performances of sand predicted by this method proved relevant to the assessment of the likely occur~ice o_~ liquefactiom for wide ranges cf lomding conditions.
478 ISHIHARA, K YASL"DA,S ~d l~luefaetion i,n hollo,~ cylinder torsion under irr eg.,lar excitation. SOILS FOUND.VIS, NI,1975, P45- 59. The authors used torsion shear test apparatus to perform a number of liquefaction tests on h o l ~ cylindrical samples of saturated sand encased in a triaxial cell. With this equipment smy desired load time history could be applied to a speclm~. The authors were able to establish rel%tionships between the amplit~le of shear stress