Marine geological disasters occurred frequently in the deep-water slope area of the northern South China Sea,especially submarine landslides,which caused serious damage to marine facilities.The cyclic elastoplastic mo...Marine geological disasters occurred frequently in the deep-water slope area of the northern South China Sea,especially submarine landslides,which caused serious damage to marine facilities.The cyclic elastoplastic model that can describe the cyclic stress-strain response characteristic for soft clay,is embedded into the coupled Eulerian-Lagrangian(CEL)algorithm of ABAQUS by means of subroutine interface technology.On the basis of CEL technique and undrained cyclic elastoplastic model,a method for analyzing the dynamic instability process of marine slopes under the action of earthquake load is developed.The rationality for cyclic elastoplastic constitutive model is validated by comparing its calculated results with those of von Mises model built in Abaqus.The dynamic instability process of slopes under different conditions are analyzed.The results indicate that the deformation accumulation of soft clay have a significant effect on the dynamic instability process of submarine slopes under earthquake loading.The cumulative deformation is taken into our model and this makes the calculated final deformation of the slope under earthquake load larger than the results of conventional numerical method.When different contact conditions are used for analysis,the smaller the friction coefficient is,the larger the deformation of slopes will be.A numerical analysis method that can both reflect the dynamic properties of soft clay and display the dynamic instability process of submarine landslide is proposed,which could visually predict the topographies of the previous and post failure for submarine slope.展开更多
In the paper. a visco-elasto plastic constitutive model and a method for determining model parameters for soft clay are presented. In this model total strain of soft clay is assumed to be divided into three parts: ins...In the paper. a visco-elasto plastic constitutive model and a method for determining model parameters for soft clay are presented. In this model total strain of soft clay is assumed to be divided into three parts: instantaneous elastic, visco-elastic and visco-plastic. The characteristics of instantaneous and visco-elastic deformation of soft clay are simulated by Merchant's model, the plastic is by a model with two yield surfaces. And related constitutive equation is conducted. A number of stress-controlled triaxial tests are performed to calculated the model parameters. The visco-elasto-plastic model is used for analysis of the displacement of an embankment on soft ground by use of three-dimensional finite element method. The predicted settlements agree well with the measured data. It is indicated that the viscous characteristics should be taken into account in deformation analysis for soft clay.展开更多
基金This work was supported by the National Natural Science Foundation of China(NSFC)(No.51179174).
文摘Marine geological disasters occurred frequently in the deep-water slope area of the northern South China Sea,especially submarine landslides,which caused serious damage to marine facilities.The cyclic elastoplastic model that can describe the cyclic stress-strain response characteristic for soft clay,is embedded into the coupled Eulerian-Lagrangian(CEL)algorithm of ABAQUS by means of subroutine interface technology.On the basis of CEL technique and undrained cyclic elastoplastic model,a method for analyzing the dynamic instability process of marine slopes under the action of earthquake load is developed.The rationality for cyclic elastoplastic constitutive model is validated by comparing its calculated results with those of von Mises model built in Abaqus.The dynamic instability process of slopes under different conditions are analyzed.The results indicate that the deformation accumulation of soft clay have a significant effect on the dynamic instability process of submarine slopes under earthquake loading.The cumulative deformation is taken into our model and this makes the calculated final deformation of the slope under earthquake load larger than the results of conventional numerical method.When different contact conditions are used for analysis,the smaller the friction coefficient is,the larger the deformation of slopes will be.A numerical analysis method that can both reflect the dynamic properties of soft clay and display the dynamic instability process of submarine landslide is proposed,which could visually predict the topographies of the previous and post failure for submarine slope.
基金This work was financially supported by the Teaching and Research Award Fund for Outstanding Young Teachers in Higher Education Institutions of Ministry of Education.P.R.China
文摘In the paper. a visco-elasto plastic constitutive model and a method for determining model parameters for soft clay are presented. In this model total strain of soft clay is assumed to be divided into three parts: instantaneous elastic, visco-elastic and visco-plastic. The characteristics of instantaneous and visco-elastic deformation of soft clay are simulated by Merchant's model, the plastic is by a model with two yield surfaces. And related constitutive equation is conducted. A number of stress-controlled triaxial tests are performed to calculated the model parameters. The visco-elasto-plastic model is used for analysis of the displacement of an embankment on soft ground by use of three-dimensional finite element method. The predicted settlements agree well with the measured data. It is indicated that the viscous characteristics should be taken into account in deformation analysis for soft clay.
