Residual shear strength of unsaturated soils via suction-controlled ring shear testing

ASTM Standard D6467-06a, 2006 ASTM Standard D7608-10, 2010 Bishop, 1971, A new ring shear apparatus and its application to the measurement of residual strength, Geotechnique, 21, 273, 10.1680/geot.1971.21.4.273 Bromhead, 1979, A simple ring shear apparatus, Ground Eng., 12, 40 Bromhead, 1983, A comparison of alternative methods of measuring the residual strength of London clay, Ground Eng., 16, 39 Feuerharmel, 2006, Determination of the shear strength parameters of two unsaturated colluvium soils using the direct shear test, vol. 1, 1181 Fredlund, 1994, Equations for the soil–water characteristic curve, Can. Geotech. J., 31, 521, 10.1139/t94-061 Fredlund, 1978, The shear strength of unsaturated soils, Can. Geotech. J., 15, 313, 10.1139/t78-029 Hossain, 2010, Behavior of a compacted completely decomposed granite soil from suction controlled direct shear tests, J. Geotech. Geoenviron. Eng., 136, 189, 10.1061/(ASCE)GT.1943-5606.0000189 Hoyos, 2001, Development of a stress/suction-controlled true triaxial testing device for unsaturated soils, Geotech. Test. J. ASTM, 24, 5, 10.1520/GTJ11277J Hoyos, 2011, A servo/suction-controlled ring shear apparatus for unsaturated soils: development, performance, and preliminary results, Geotech. Test. J. ASTM, 34, 413 Hoyos, 2012, Refined true triaxial apparatus for testing unsaturated soils under suction-controlled stress paths, Int. J. Geomech. ASCE, 12, 281, 10.1061/(ASCE)GM.1943-5622.0000138 Infante Sedano, 2007, Modified ring shear apparatus for unsaturated soil testing, Geotech. Test. J. ASTM, 30, 1 Lu, 2004 Lupini, 1981, The drained residual strength of cohesive soils, Geotechnique, 31, 181, 10.1680/geot.1981.31.2.181 Merchán, 2011, An adapted ring shear apparatus for testing partly saturated soils in the high suction range, Geotech. Test. J. ASTM, 34, 433 Salman, 1995 Skempton, 1985, Residual strength of clays in landslides, folded strata, and the laboratory, Geotechnique, 35, 3, 10.1680/geot.1985.35.1.3 Stark, 1997, Slope stability analyses in stiff fissured clays, J. Geotech. Geoenviron. Eng., 123, 335, 10.1061/(ASCE)1090-0241(1997)123:4(335) Stark, 1992, Bromhead ring shear test procedure, Geotech. Test. J., 15, 24, 10.1520/GTJ10221J Vanapalli, 1996, Model for the prediction of shear strength with respect to soil suction, Can. Geotech. J., 33, 379, 10.1139/t96-060 Vaunat, 2006, Residual strength of a low plasticity clay at high suctions, vol. 1, 1279 Vaunat, 2007, Residual strength of clays at high suctions, vol. 2, 151 Velosa, 2011 Zhan, 2006, Shear strength characteristics of an unsaturated expansive clay, Can. Geotech. J., 43, 751, 10.1139/t06-036