摘要
With high speed development of the city construction in Tianjin Binhai New Area,a great deal of underground engineering such as deep foundation excavations came forth.This made the research on the properties of soft clay in Binhai New Area become necessary,especially for the unloading properties.Using the improved triaxial equipment,a series of ko consolidation and undrained tests have been carried out to study the unloading deformation properties of the soil in Tianjin Binhai New Area.According to the experimental results,it can be conclude that the unloading deformation properties of the soft clay are relative to the stress path.The stress-strain curves of the soil under lateral or vertical unloading path can be simulated by hyperbola function and the initial tangent modulus is proportional to the confining pressure.