科研之友
微信
新浪微博
Facebook
分享链接
摘要
For study the influence of macro-pore parameters on the damage evolution of concrete under static and impact loads,a physical model of random pore structure was generated by MATLAB program based on Monte Carlo method,and the stress-strain process of macro porous concrete under uniaxial compression was simulated by a self-programed peridynamic program. Furthermore,the accuracy of the calculation results was verified by uniaxial compression experiments of concrete specimens with macro porosity of 0% ~ 40% . The concrete mortar specimens were prepared with polystyrene spheres which melt at high temperature into voids. Finally,the crack germination and expansion of the macro porous concrete under blasting impact loads were simulated. The results show that the porosity has a significant effect on the mechanical properties of macro porous concrete materials. With the increase of porosity,the density,compressive strength,elastic modulus and longitudinal wave velocity of samples continuously decreases,respectively. When the porosity reaches 30%,the effect of porosity on the axial compressive strength is weakened,and the stress before the peak has a drop phenomenon. The concrete samples with zero porosity have obvious compression shear failure mode under the impact load without confining pressure,while the existence of a large number of pores leads to tensile or shear failure of concrete skeleton. Under the same impact load,the failure of concrete with large porosity is more severe,which indicates that porosity plays an important role in energy dissipation of concrete under impact load. ? 1994-2023 China Academic Journal Electronic Publishing House.
- 单位
