Deformation Characteristics of Foundation Pit Soils under Lateral Unloading

The k0 consolidation–lateral unloading plane strain experiment and conventional triaxial experiment are made with the GDS triaxial apparatus using the silty clay from a deep foundation pit peripheral active area.The results show that: the stress–strain curves of two stress paths tests are similar to a hyperbolic type;they are non-linear and show the phenomenon of strain hardening.the principal stress difference of unloading test is less than that of loading test.For the lateral strain generated by the unloading test,the finite element software is used to simulate lateral unloading test.The ratio between Δe22 and Δe32 of the silty clay is determined.The expression of tangent modulus of the silty clay under lateral unloading is further deduced.