Dynamic Shearing Constitutive Model Of Lithologic Matrial And Application In Finite Element Analysis

The dynamic shearing experiment of the lithologic matrial indicates that the lithologic matrial is rate-dependent material. There are two influencing factors on dynamic response of it-the strengthening effect of strain rate and the weakening effect of damage. But when analysising the stability of slope under the earthque loads, we use the material static property instead of dynamic characters, or increte the material's parameters, or reduce the degree of safety. The main reason is that the constitutive equations in the general-purpose software, such as elastic material, elastic-plastic material, concrete material, Molor-Coulomb material are based on the ststic state.Most of dams and electric station are established on our country's western, where earthquake happened frequently, the alysising the earthquake-resistant and stability of slop are important, so, creating the suitable lithologic materal's dynamic shearing constitutive model and realizing in the FEM are necessary. The main work done in this paper is as follows:(1) based on the results of shearing characteristics of lithological material on the shaking table of Hohai university and the predecessor's achievements, the author summarize two main factors that affect the shearing characteristics- the strengthening effect of strain rate and the weakening effect of damage ,find their evolvement regular, and lay the foundation of lithologic material's dynamic shearing constitutive model.(2) Draw lessons from the viscoplastic theory of Perzyna, indroduce the strengthening effect of strain rate and the weakening effect of damage, introduce the the strengthening effect of strain rate and the weakening effect of damage into the constitutive model, develop the lithologic material's dynamic shearing constitutive model that considerate the fatigue damage.(3) In order to expand the general-purpose software function and satify the specific computation goal, on the base of user subroution and Fortran language, this paper develop the dynamic shearing costisitive model of litholopic material.(4) Invoking the user supply material and making use of FEM to analyze the test model, later comparing the calculated results to the test results.(5) Finally this paper uses Mohr-Coulomb material and the user supply material to analyze the dynamic response of the rock slop on Baise Hydraulic Power plant. The results illustrate that the program composition has the general serviceability.