Load Carrying Capacity Calculation Of Brittle-Plastic Structures And Its Application In Engineering Practice

In the work,a damage surface(which is the external surface of the strain-softening domain)perturbation formulation of lood carrying capacity problems ofbrittle-plastic structures is presented and analytical solutions of several typicalboundary value problems are constructed to show the efficiency of the new for-mulation.Working principal and controlling method of MTS815.03 and/or Mayes electro-hydraulic serve cantrol festing system are briefly described.Propcrties of the wholeprocess of load-displacement curves of the concerned rock and coal mass arediscussed.It's shown from the obtained experimental results that the So-Galled brittle-plasticity model is suitable for describing the constitutive behaviour of such materialsas rock and coal.Matrix representation and integration of brittle-plastic constitutiverelation in 6-dimensional stress space are derived based on the laws expressedin strain-space plesticity formalation. The invalved initial and subsequent yield surfacesare of the type of von-Mises,Mohr-Coulomb,H.Tresca,Drucker-Prager,Zienhiewicz-Pande,and 20 on.A finite element numerical procedure is developed implementingthe above-mentioned brittle-plasticity constitutive models,and the excavation process is properly simulated in the program.Application of the procedare to proctical coolpillar design problem is discussed.