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Electromagnetic forces and soil strength
35A
Fracture processes in rocks 339 MOON, CF SII~'FIELD POLYTECH. GB The failure mechanism of quickclay soils. A model approach. S y ~ s i u m . Snmmmries of papers. MIDLAND SOIL MECH.FOUND.~GNG.SOC.SYMP.OF ENGNG.BEHAVIOUR OF GLACIAL MAT. ,BIRMINGHAM, APRIL,1975. Experlm~gts with a model quickclay soil composed of qusrtz particles in the cls~ size range has zero plasticity and displsys extreme dilat~ncy. Shear-rate blockage is exhibited, a mechs.nism by which a material behaves either as a brittle solid or as a viscous fluid at the same moisture eontemt. The physical state depends solely upon shearing rate. This brittle solid-viscous fluid transition is strongly reminiscent of the failure m~de of quickclays. The geotechnical and rhsological properties of this model quickclay material have been investigated and are discussed and compared with those of real quickclay soils. Auth.
Strength characteristics 34o ISRM Suggested methods for determining shear strength.9F,lT. ISRM CO~4ISSION ON STANDARD.LAB.FIELD TESTS. COMMITTEE ON FImWD TESTS,DOC~,N1,FEB.1974,2BP. The report is presented in three parts:-l) Suggested method for insitu determination of direct shear strength; 2 ) Suggested method for laboratory determination of direct shear strength; 3 ) Suggested method for In-situ determination of shear strength using a torsional shear test. For each test the scope of the test, apparatus used, procedure (Incorl~rating ~reparation,consolidation and shearing), calculations and how to report results sre defined. 341 KINNER,EB LADD, CC Undrained bearing capacity of footing on clay. Conference. Session one. 5F,2T,13R. PBOC.EIGHTH INT.CONF.ON SOIL MECH.FOUND.ENGNG. MOSCOW, V!. I, 1973, I>209-215• Undrained model footing tests were performed with a r e c t a n ~ ! ~ footing resting on samples of resedimented consolidated Boston Blue clay. The bearing capacity was measured and predicted by estimating the undrained strength, and comparisons made between the two sets of data. It is shown that the effects of sample disturbance and strength anisotropy ~mst be considered in order to obtain accurate predictions of undrained stability for this sensitive clay. 342 LA ROCW~ T ~,p HOY, M TAVE~AS, F Field measurements of cohesion in Champlain clays. Conference.Session one.9F,2T, 23R. PBOC .EIGHTH INT.CONF.ON SOIL MECH.FOUND.~GNG. MOSCOW,VI.I,1973,P229-236. This paper presents the results of a comparative study between three in-situ testing methods (vane, pressure. meter and penetrometer ) to measure the undrained shear strength in deposits of a sensitive cemented clay on two different sites. The practical implications of this study are discussed in the concluslon. 343 DAVIS, EH BOOK~q, JR The effect of increasing strength with depth on the bearing capacity of clays. Authors reply to
discussion of original paper, Geotechnlque, V24, N3,1974. 1T, IR. G~DTECHNIQUE, V24, N4, DEC .1974,P690. The authors consider the problem of extending the analysis to the general cs~;e of s coheslor~ increasing linearly with depth. They question the frequency of prsatical relevance of such a situation, but believe that the solution for this csse can be recovered from the ans/~°sis for a homogeneous frictional material with a surcharge. 344 TAYLOR, RK UNIV. DURHAM, GB Influence of coal content on the peak shear strength of colliery shales.Technical note.5F,2T,2R. C~DTECHNIQUE, V24, N4, DEC. 1974, P683 -688. 345 BHASKARAN, R REG. ENGNG. COLL. CALICUT, IND Strength anisotropy in kaolinite clay. Technical note. 21F, IT. G~0TECHNIQUE, V24, N4, DEC. 1975, P674 -678. 3~ MDORE, CA OHIO STATE UNIV.COLUMBUS,USA MITCHELL, JK UNIV. CALIF .B~K~T ~Y, USA Electromagnetic forces and soil strength. IOF,IT,26R. GEOTECHNIQUE,VZ4,N~, DEC. 1974, P627-640. Ana/~tical techniques for expressing electromagnetic forces of interaction in soils including electrostatic and electrodynamic forces are described. The interaction forces are expressed in termo of the physical properties of the individual components of the system. Re. sults of experimental investigations (triaxial shear, vane shear and activation energy for creep tests on clay soils with pore-fluids exhibiting a variety of static dielectric constants ) are presented. 347 MCKINIAY, DG UNIV. STRATHCLYDE, SCOTLAND, GB TOMLINSON, M~ W IMPEY LABS .LTD.GB ANDERSON, WF UNIV. SHEFFIELD, QB Observations on the undrained strength of a glacial till. 9F, 2T,13R. GEOTEC"HNIQUE,V24, N4, DEC. 1974, P503- 516. Ssm~llng and testing procedures when applied to the determination of undrained sheer strength of stiff unweathered lodgement tills in the Glasgow district of Central Scotland are compared. Values of the undrained strength depend, in pert, on the method of interpretation of the test data. Coupled U100 samplers were found to be the most satisfactory of the common comnericsl tools for extracting samples but the recovery of specimens in a satisfactory condition for testing was rather poor. The strength properties differed somewhat accord_ ing to the test procedure adopted and these differences are described. 348 MARSLAND, A BUILDING RES. ESTAB .WATFORD, GB In-situ and laboratory tests on Boulder clay at Redcar. Symposium. Summaries of papers. MIDLAND SOIL MECH.FOUND.~GNG SOC.SYMP.ON E~GNG BEHAVIOUR OF GLACIAL MAT~IALS,BIRMINGHAM, APRIL, 1975. Deep in-situ loading tests were made on a 865~au diameter plate in a 900ram diameter borehole at three levels in the Boulder clay and undrained shear strengths were estimated from the ultimate loads measured. Undrained triaxial tests were made on 98ram diameter samples taken by pushing in thin-walled sampling tubes. The shear strength obtained from these tests varied Considerably and the average values were higher than those estimated from the large in-situ tests. The moduli determined from the triaxial tests ware however, only i/h of those estimated from the ]oad settlement curves obtained in the in-situ tests. Auth.
Fracture processes in rocks 339 MOON, CF SII~'FIELD POLYTECH. GB The failure mechanism of quickclay soils. A model approach. S y ~ s i u m . Snmmmries of papers. MIDLAND SOIL MECH.FOUND.~GNG.SOC.SYMP.OF ENGNG.BEHAVIOUR OF GLACIAL MAT. ,BIRMINGHAM, APRIL,1975. Experlm~gts with a model quickclay soil composed of qusrtz particles in the cls~ size range has zero plasticity and displsys extreme dilat~ncy. Shear-rate blockage is exhibited, a mechs.nism by which a material behaves either as a brittle solid or as a viscous fluid at the same moisture eontemt. The physical state depends solely upon shearing rate. This brittle solid-viscous fluid transition is strongly reminiscent of the failure m~de of quickclays. The geotechnical and rhsological properties of this model quickclay material have been investigated and are discussed and compared with those of real quickclay soils. Auth.
Strength characteristics 34o ISRM Suggested methods for determining shear strength.9F,lT. ISRM CO~4ISSION ON STANDARD.LAB.FIELD TESTS. COMMITTEE ON FImWD TESTS,DOC~,N1,FEB.1974,2BP. The report is presented in three parts:-l) Suggested method for insitu determination of direct shear strength; 2 ) Suggested method for laboratory determination of direct shear strength; 3 ) Suggested method for In-situ determination of shear strength using a torsional shear test. For each test the scope of the test, apparatus used, procedure (Incorl~rating ~reparation,consolidation and shearing), calculations and how to report results sre defined. 341 KINNER,EB LADD, CC Undrained bearing capacity of footing on clay. Conference. Session one. 5F,2T,13R. PBOC.EIGHTH INT.CONF.ON SOIL MECH.FOUND.ENGNG. MOSCOW, V!. I, 1973, I>209-215• Undrained model footing tests were performed with a r e c t a n ~ ! ~ footing resting on samples of resedimented consolidated Boston Blue clay. The bearing capacity was measured and predicted by estimating the undrained strength, and comparisons made between the two sets of data. It is shown that the effects of sample disturbance and strength anisotropy ~mst be considered in order to obtain accurate predictions of undrained stability for this sensitive clay. 342 LA ROCW~ T ~,p HOY, M TAVE~AS, F Field measurements of cohesion in Champlain clays. Conference.Session one.9F,2T, 23R. PBOC .EIGHTH INT.CONF.ON SOIL MECH.FOUND.~GNG. MOSCOW,VI.I,1973,P229-236. This paper presents the results of a comparative study between three in-situ testing methods (vane, pressure. meter and penetrometer ) to measure the undrained shear strength in deposits of a sensitive cemented clay on two different sites. The practical implications of this study are discussed in the concluslon. 343 DAVIS, EH BOOK~q, JR The effect of increasing strength with depth on the bearing capacity of clays. Authors reply to
discussion of original paper, Geotechnlque, V24, N3,1974. 1T, IR. G~DTECHNIQUE, V24, N4, DEC .1974,P690. The authors consider the problem of extending the analysis to the general cs~;e of s coheslor~ increasing linearly with depth. They question the frequency of prsatical relevance of such a situation, but believe that the solution for this csse can be recovered from the ans/~°sis for a homogeneous frictional material with a surcharge. 344 TAYLOR, RK UNIV. DURHAM, GB Influence of coal content on the peak shear strength of colliery shales.Technical note.5F,2T,2R. C~DTECHNIQUE, V24, N4, DEC. 1974, P683 -688. 345 BHASKARAN, R REG. ENGNG. COLL. CALICUT, IND Strength anisotropy in kaolinite clay. Technical note. 21F, IT. G~0TECHNIQUE, V24, N4, DEC. 1975, P674 -678. 3~ MDORE, CA OHIO STATE UNIV.COLUMBUS,USA MITCHELL, JK UNIV. CALIF .B~K~T ~Y, USA Electromagnetic forces and soil strength. IOF,IT,26R. GEOTECHNIQUE,VZ4,N~, DEC. 1974, P627-640. Ana/~tical techniques for expressing electromagnetic forces of interaction in soils including electrostatic and electrodynamic forces are described. The interaction forces are expressed in termo of the physical properties of the individual components of the system. Re. sults of experimental investigations (triaxial shear, vane shear and activation energy for creep tests on clay soils with pore-fluids exhibiting a variety of static dielectric constants ) are presented. 347 MCKINIAY, DG UNIV. STRATHCLYDE, SCOTLAND, GB TOMLINSON, M~ W IMPEY LABS .LTD.GB ANDERSON, WF UNIV. SHEFFIELD, QB Observations on the undrained strength of a glacial till. 9F, 2T,13R. GEOTEC"HNIQUE,V24, N4, DEC. 1974, P503- 516. Ssm~llng and testing procedures when applied to the determination of undrained sheer strength of stiff unweathered lodgement tills in the Glasgow district of Central Scotland are compared. Values of the undrained strength depend, in pert, on the method of interpretation of the test data. Coupled U100 samplers were found to be the most satisfactory of the common comnericsl tools for extracting samples but the recovery of specimens in a satisfactory condition for testing was rather poor. The strength properties differed somewhat accord_ ing to the test procedure adopted and these differences are described. 348 MARSLAND, A BUILDING RES. ESTAB .WATFORD, GB In-situ and laboratory tests on Boulder clay at Redcar. Symposium. Summaries of papers. MIDLAND SOIL MECH.FOUND.~GNG SOC.SYMP.ON E~GNG BEHAVIOUR OF GLACIAL MAT~IALS,BIRMINGHAM, APRIL, 1975. Deep in-situ loading tests were made on a 865~au diameter plate in a 900ram diameter borehole at three levels in the Boulder clay and undrained shear strengths were estimated from the ultimate loads measured. Undrained triaxial tests were made on 98ram diameter samples taken by pushing in thin-walled sampling tubes. The shear strength obtained from these tests varied Considerably and the average values were higher than those estimated from the large in-situ tests. The moduli determined from the triaxial tests ware however, only i/h of those estimated from the ]oad settlement curves obtained in the in-situ tests. Auth.