Experimental Study On Three-dimensional Characteristic Of Saturated Soft Clay Under Partial Drainage Conditions

The characteristics of soft clay such as low strength and large water content have always been an inevitable problem for highway,railway,airport runway and other traffic engineering.The post-construction settlement of infrastructure which is built on soft soil foundation directly affects its service performance.The settlement of foundation soil under the action of long-term traffic load will directly affect the comfort and safety of driving,and also increase the cost for the later maintenance.The study on the deformation characteristics of saturated clay under cyclic stress is the key to solve problems mentioned above.In this paper,a series of tests were carried out on the true triaxial system of wenzhou university to study the three-dimensional dynamic characteristics of the remolded soft clay in different drainage and consolidation conditions.The main works carried out in this paper are as follows:?1?With the aid of experimental equipment such as true triaxial,the anisotropy induced by embankment loading is simulated under three-dimensional stress state.The specimens were consolidated in anisotropy by changing the major,intermediata,minor principal stress.The shear strength and stress-strain relationship of saturated soft clay under anisotropic consolidation were obtained by strain controlled compression test.The effect of anisotropy consolidation on static strength of soil is studied.?2?Considering that subgrade clay is usually overconsolidated,pore water is partially drained,and the stress state is in three dimensional.The one way deformation characteristics of normal and overconsolidated clay under partial drainage conditions were discussed based on true triaxial test.Emphasis is put on the effects of CSR,OCR and b_cycon the permanent strain components including major,intermediate and minor principal stress.?3?In order to compare the influence of drainage conditions on the dynamic properties of soft clay,a series of cyclic tests were carried out for remolded soft clay under undrained and partially drained conditions respectively.Results show that the strain accumulation rules are quite different under different drainage conditions.