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Interpretation of shear moduli from cone pressuremeter tests in sand
PROPERTIES:DEFORMATION & STRENGTH 944071 Calibration c h a m b e r studies of piezocone test in cohesive soils P . U . Kump, G. Z. Voyiadjis & M . T . Tumay, Journal of Geotechnical Engineering - ASCE, 120(1), 1994, pp 81-107. Results of miniature piezocone penetration tests (PCPT) on cohesive soil specimens in a calibration chamber system are presented. The influence of soil type, stress history, penetration boundary conditions, and filter locations on PCPT data are investigated. An increase in the strength of the soil around the cone penetrometer is observed when penetration is resumed after a dissipation test. The penetration depth recruited to attain a steady excess pore pressure value at the tip of the cone is influenced by the overconsolidation ratio and the lateral stress coefficient. The empirical values of the cone factor and the pore pressure factor are found to be strongly influenced by the lateral stress and the plasticity index. The tip resistance measured during the miniature quasi-static friction cone penetration tests (QCPT) are consistently lower than the values obtained from the PCPT. -from Authors 944072 Physicomechanical characteristics of heteroeneous compacted soils I. Krntov & N. T. Tanatarov, Soil Mechanics & Foundation Engineering, 30(3), 1993, pp 79-84; translated from: Osnovaniya, Fundamenty i Mekhanika Gruntov, 30(3), 1993, pp 2-5. Presents results of investigations of the strength and deformation characteristics o f heterogeneous soils and their relation with respect to the composition, density, water content, and degree of compaction. The effect of the composition on the maximum dry density of the soil and the optimal water content is established. Conclusions are drawn about the possibility of use of heterogeneous soils as earth pads, grading fills, backfills, etc. in place of soils of the same type or of homogeneous characteristics. -Journal summary 944073 Hyperbolic stress-strain p a r a m e t e r s for silts T. D. Stark, R. M. Ebeling & J. J. Vettel, Journal of Geotechnical Engineering - ASCE, 120(2), 1994, pp 420-441. A series of isotropicaily consolidated-drained and consolidated-undrained triaxial tests were performed on freshly deposited, normally consolidated silts and clayey silts to provide guidance for selecting hyperbolic parameters for these materials. The effect of clay mineral content and dry unit weight on the hyperbolic parameters was investigated. The transition from dilative to contractive shear behavior is controlled by clay mineralogy. Due to the dilative behavior of the normally consolidated silt mixtures, failure criteria of maximum deviator stress and maximum pore-water pressure were used to obtain the Mohr-Coulomb shear strength parameters from the drained and undrained triaxial tests. -from Authors
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the measurement of soil stiffness. In particular it is shown that the cone pressuremeter test can gxve reliable values of unload-reload shear modulus. The typical shape o f unloadreload loops is examined, and two procedures to calculate the shear modulus ate proposed. The shear moduli calculated from measurements made with strain arms and those calculated from volume change measurements are compared. The method is presented that allows the relevant stress level acting around the pressuremeter during the test to be taken into account in the interpretation of measurements of the shear modulus. The values of the moduli obtained from the cone pressuremeter are comparable with those obtained from the self-boring pressuremeter. -Authors 944076 Influence of relative density and stress level on the bearing capacity of sands P. Simonini, International Journal for Numerical & Analytical Methods in Geomechanics, 17(12), 1993, pp 871-890. A finite element approach is presented to determine the bearing capacity o f shallow footings on silica sand deposits. The approach can take into account the effects of relative density and stress level on the shear strength of granular soil and is applicable to a fairly large effective stress range. The strength of sand is characterized by a non-linear Mohr-Coulomb criterion which depends on maximum and critical friction angles, widely usedparameters in engineering practice. -from Author 944077 Cone penetration in cemented sands: bearing capacity interpretation A. J. Puppala, B. Acar & K. Senneset, Journal of Geotechnical Engineering - ASCE, 119(12), 1993, pp 1990-2001. Two bearing-capacity theories are used to predict conepenetration tip resistance and sleeve friction in weakly cemented sands. These theories use the rigid-plastic assumption for stress-deformation behavior of soils. Both theories provided good predictions of tip resistance when compared with experimental values obtained in limited penetration tests conducted in the laboratory. Predicting sleeve friction with bearing-capacity theories necessitated an estimate of the lateral earth pressures. The recorded sleeve-friction values imptied hi[~lxer lateral pressures than the K 0 state of stress. Tip resmtance and friction resistances predicted by these theories are used to propose a preliminary classification, identification, and analysis scheme for cemented sand deposits. -from Authors 944078 Mechanical p r o p e r t y of fault gouge and its constitutive relation (in Chinese) Xi Daoying, Xie Duan & Tang Lei, Earthquake (Beijing), 6, 1993, pp 55-60. A series of experiments were performed on yellow-green fault gouge at Dashuichang along Tancheng-Lujiang fault zone and its constitutive characteristics are discussed. This constitutive model which is suitable to a larger range can describe the elastic behaviour, failure behaviour and the cap behaviour of the fault gouge. -English summary
944074 Behaviour of loose sand u n d e r simultaneous increase in stress ratio and principal stress rotation D. Wijewick_reme & Y. P. Vaid, Canadian Geotechnical Journal, 30(6), 1993, pp 953-964. The drained behaviour of loose sands under simultaneous increase in stress ratio and principal stress rotation is investigated. The hollow cylinder torsional device is adopted as the testing device. It is demonstrated that the strain response under any general increasing R - ct hath in the domain of R < 2 and c¢_ < 45" can be predictg¢[ using the results of a limited num~ber of tests characterizing that domain. Strain increment direction ct^o is shown to be approximately coincident with and totally governed by the stress increment direction aa¢ , when the stress increment direction c ~ is ]?referentially reclined towards the vertical deposition direct/on. -from Authors
944079 Anisotropic strength properties of a q u a r t z schist saprolite O. Ogunsanwo, Bulletin - International Association of Engineering Geology, 48, 1993, pp 89-92. Strength anisotropy in a quartz schist saprolite is examined via shear tests in which the inclinations of t h e v l a n e s of s.chistosity to the compression axis were variecf. Results obtained are anomalous when compared with the general trend of results obtained for other schistose formations. The cementation of the soil particles along the planes of schistosity by the goethite present in the saprolite is deemed responsible for the anomaly. -Author
944075 I n t e r p r e t a t i o n of s h e a r moduli from cone p r e s s u r e m e t e r tests in sand G . T . Houlsby & F. Schnaid, Geotechnique, 44(1), 1994, pp 147-164. The interpretation of the elastic shear modulus obtained from cone pressuremete'r tests is examined to assess the influence o f installation disturbance and other factors on
944080 Triaxial compressive strength of a stylolitic, medium grained m a r b l e from the K u a l a L u m p u r limestone J.K. Raj, Warta Geologi, 19(5), 1993, pp 197-203. Hock Cell tests of a stylolitic, medium grained marble from the Kuala Lumpur Limestone show that its failure under triaxial conditions of loading can be discussed using the
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the measurement of soil stiffness. In particular it is shown that the cone pressuremeter test can gxve reliable values of unload-reload shear modulus. The typical shape o f unloadreload loops is examined, and two procedures to calculate the shear modulus ate proposed. The shear moduli calculated from measurements made with strain arms and those calculated from volume change measurements are compared. The method is presented that allows the relevant stress level acting around the pressuremeter during the test to be taken into account in the interpretation of measurements of the shear modulus. The values of the moduli obtained from the cone pressuremeter are comparable with those obtained from the self-boring pressuremeter. -Authors 944076 Influence of relative density and stress level on the bearing capacity of sands P. Simonini, International Journal for Numerical & Analytical Methods in Geomechanics, 17(12), 1993, pp 871-890. A finite element approach is presented to determine the bearing capacity o f shallow footings on silica sand deposits. The approach can take into account the effects of relative density and stress level on the shear strength of granular soil and is applicable to a fairly large effective stress range. The strength of sand is characterized by a non-linear Mohr-Coulomb criterion which depends on maximum and critical friction angles, widely usedparameters in engineering practice. -from Author 944077 Cone penetration in cemented sands: bearing capacity interpretation A. J. Puppala, B. Acar & K. Senneset, Journal of Geotechnical Engineering - ASCE, 119(12), 1993, pp 1990-2001. Two bearing-capacity theories are used to predict conepenetration tip resistance and sleeve friction in weakly cemented sands. These theories use the rigid-plastic assumption for stress-deformation behavior of soils. Both theories provided good predictions of tip resistance when compared with experimental values obtained in limited penetration tests conducted in the laboratory. Predicting sleeve friction with bearing-capacity theories necessitated an estimate of the lateral earth pressures. The recorded sleeve-friction values imptied hi[~lxer lateral pressures than the K 0 state of stress. Tip resmtance and friction resistances predicted by these theories are used to propose a preliminary classification, identification, and analysis scheme for cemented sand deposits. -from Authors 944078 Mechanical p r o p e r t y of fault gouge and its constitutive relation (in Chinese) Xi Daoying, Xie Duan & Tang Lei, Earthquake (Beijing), 6, 1993, pp 55-60. A series of experiments were performed on yellow-green fault gouge at Dashuichang along Tancheng-Lujiang fault zone and its constitutive characteristics are discussed. This constitutive model which is suitable to a larger range can describe the elastic behaviour, failure behaviour and the cap behaviour of the fault gouge. -English summary
944074 Behaviour of loose sand u n d e r simultaneous increase in stress ratio and principal stress rotation D. Wijewick_reme & Y. P. Vaid, Canadian Geotechnical Journal, 30(6), 1993, pp 953-964. The drained behaviour of loose sands under simultaneous increase in stress ratio and principal stress rotation is investigated. The hollow cylinder torsional device is adopted as the testing device. It is demonstrated that the strain response under any general increasing R - ct hath in the domain of R < 2 and c¢_ < 45" can be predictg¢[ using the results of a limited num~ber of tests characterizing that domain. Strain increment direction ct^o is shown to be approximately coincident with and totally governed by the stress increment direction aa¢ , when the stress increment direction c ~ is ]?referentially reclined towards the vertical deposition direct/on. -from Authors
944079 Anisotropic strength properties of a q u a r t z schist saprolite O. Ogunsanwo, Bulletin - International Association of Engineering Geology, 48, 1993, pp 89-92. Strength anisotropy in a quartz schist saprolite is examined via shear tests in which the inclinations of t h e v l a n e s of s.chistosity to the compression axis were variecf. Results obtained are anomalous when compared with the general trend of results obtained for other schistose formations. The cementation of the soil particles along the planes of schistosity by the goethite present in the saprolite is deemed responsible for the anomaly. -Author
944075 I n t e r p r e t a t i o n of s h e a r moduli from cone p r e s s u r e m e t e r tests in sand G . T . Houlsby & F. Schnaid, Geotechnique, 44(1), 1994, pp 147-164. The interpretation of the elastic shear modulus obtained from cone pressuremete'r tests is examined to assess the influence o f installation disturbance and other factors on
944080 Triaxial compressive strength of a stylolitic, medium grained m a r b l e from the K u a l a L u m p u r limestone J.K. Raj, Warta Geologi, 19(5), 1993, pp 197-203. Hock Cell tests of a stylolitic, medium grained marble from the Kuala Lumpur Limestone show that its failure under triaxial conditions of loading can be discussed using the