One-dimensional Consolidation Theory And Experimental Study Of Soft Clay

Soft clay is a special soil with both viscous and elastic properties.It is widely distributed in coastal areas and the main feature is rheology.Since Terzaghi put forward the classical one-dimensional consolidation theorem in 1925,the study of soil consolidation theory has attracted great attention of scholars at home and abroad.Until now some preferable research results have been obtained.As a special kind of soil,the definite and reliable conclusion on the consolidation theory of soft clay has not yet been reached.The study combined theoretical deduction analysis with dynamic triaxial test study of marine soft clay in Zhoushan,effectively discussed the one-dimensional consolidation of saturated soft clay,further improved the one-dimensional consolidation theory of soft clay,and provided a theoretical basis for engineering practice.The main work and achievements are as follows:1?Based on the viscoelastic Kelvin model and Laplace transform method of fractional-order elastic pot component modification,the one-dimensional consolidation theory equation of soft clay under constant load,exponential load and cyclic loading were obtained,and the Crump inversion method was used to obtain the theoretical equation.The effects of fractional order,viscous coefficient and different load forms on one-dimensional consolidation of saturated soft clay were analyzed by using the obtained semi-analytical solutions.The results showed that different load forms and different parameter choices had a greater impact on the one-dimensional consolidation of soft clay.2?For the saturated soft clay,combined with the improved fractional Kelvin model of the elastic pot component,and considering the variation of the stress along the depth in the soil,the one-dimensional consolidation semi-analytical solution was obtained by using Laplace transform.The validity of the model was illustrated by comparison with the literature results.The effects of different fractional order,different total stress ratios and different linear loadings on the consolidation and saturated pore water pressure of saturated soft clay were analyzed in detail,and the consolidation and settlement mechanism of saturated soft clay was reproduced.3?The advanced functions and test procedures of the WILLE dynamic triaxial apparatus were introduced in detail.The conventional triaxial consolidation test and cyclic dynamic load loading test of marine soft clay in Yushan Island,Zhoushan were carried out,The semi-analytical solution derived from the theory was compared with the experimental results.The results showed that the theoretical and experimental settlement values were basically consistent,indicating that the viscoelastic model had a better advantage in describing the consolidation mechanism of soft clay.The effects of different cyclic stress ratios on the samples were investigated by cyclic loading test.