Experimental Study On Reconstituted Loess About Torsion Shear Of Hollow Circular Cylinder

Loess is a kind of widely distributed soil in China. Compared with other types of soil, loess formed strong structural in the deposition process, and because of the loess belonging to northwest region that is arid and semiarid area, which make it have structural strong water sensitivity. The characteristics of loess affect its stress—strain relationship and strength properties, wet depression engineering properties. With the implementation of the western development strategy and the "The Belt and Road" strategy, the number and size of northwest loess area infrastructure construction is increasing rapidly, it has more practical significance in the research of traffic load on engineering properties of unsaturated loess. On the basis of reading and analyzing a large amount of literature materials, this paper makes a study on the reconstruction of Loess by means of ZJU—HCA hollow cylinder torsional shear apparatus:(1) Through the remodeling loess under different moisture content of static triaxial consolidated undrained tests. The stress and strain volume change of the relationship, in the water rate is low, the confining pressure is small, the loess of the stress strain curve was weak strain hardening type; in high water content and confining pressure is larger, the Loess should stress — strain curves show strain hardening. When the soil sample is damaged, it is a drum shaped character, which is the shear shrinkage.(2) Through on structure strength under the same conditions of undisturbed loess and remolded loess contrast test unearthed play rules is extreme point is play a structural strength limit state, structure yielding, extremum point before the structural strength of the soil has not been destroyed, structural strength with the strain increasing rapidly play small deformation in, after the extreme point structure is completely destroyed, should stress strain curves showed a downward trend, structure intensity gradually decreases until it reaches a point, inside the soil particles are rearranged.(3) The principal stress axes rotation directional shear test that moisture content, principal stress off-axis angle, in main force coefficient of anisotropy should be effects of stress and strain and anisotropy should be the relationship between stress and strain are obtained. Comparing these law advice to cut to strain as shear failure criterion of remolded loess.