Analysis Of Soil Constitutive Models For Numerical Simulation Of Haikou Red Clay Excavation

In recent years, with the rapid development of China’s urbanization, a variety of deep foundation pits continue to emerge, which also led to accidents caused by the excavation of much attention. Haikou as the capital of Hainan Province, is the top priority of Hainan International Tourism Island Development. Haikou’s urban construction has intensified; there are also many problems on the foundation pit engineering. The red clay of interactive marine and terrestrial deposit is widely distributed across Haikou area, which is one problem of the foundation soil foundation design and construction most frequently encountered, so it is necessary to research in the area of foundation pit engineering of the typical soil.This paper summarizes the findings of previous excavation on the basis of Haikou clay excavation as the research object, through the combination of soil tests, construction monitoring and finite element numerical simulation, the numerical analysis on excavation have been completed based on different constitutive models. This paper suggested soil constitutive model and the corresponding parameter method applicable to this kind of clay in Haikou area. The main research work and conclusions are as follows:(1) According to the red clay of interactive marine and terrestrial deposit in excavation scope, the physical and mechanical properties of this kind of clay have been obtained from a series of experiments.(2) Select Mohr-Coulomb, Drucker-Prager and modified Cambridge model this three constitutive models, the related parameters of field soil samples were determined. The calculation formulas to estimate the parameters of the modified Cambridge model have been derived which is based on the soil plasticity index.(3) Use three constitutive models in Haikou excavation numerical simulation respectively. The results show that: the impact areas of excavation were similar under three constitutive relations, but the displacement form of retaining piles, heave of pit soil, and the displacement surface of outside soil have large differences in the three models.(4) Through the excavation construction monitoring, distribution regularities of soil and retaining structure have obtained. Compare with the finite element simulation results, the modified Cambridge model gave the closer calculation results to the actual values in monitoring, as is more suitable for numerical analysis in this kind of red clay excavation.(5) Comparing numerical simulation results of foundation excavation in different finite element analysis software when the soil using the modified Cambridge mode. Adjust model parameters to fit the numerical values coincide with the measured results. The formulas of constitutive model parameters are obtained.