一种孔隙介质力学模型及在水泥基材料的应用

A MECHANICAL MODEL OF POROUS MEDIA AND ITS APPLICATION IN CEMENT MATERIALS

基于细观力学和断裂力学的基本理论提出一个新的分析模型,对孔隙介质的力学性能进行了分析.依据孔隙介质内部孔隙的几何描述和状态参数,如孔隙率、形状、尺度及分布等,通过等效夹杂理论获得孔隙介质的等效本构方程,其最终变量为应力、应变和孔隙的形态参数.根据断裂理论中材料承受载荷作用下破坏增长过程中的能量守恒,对孔隙介质变形过程中机械能、弹性应变能和载荷提供的势能进行分析,根据能量守恒定律建立能量守恒方程,其最终变量也为应力、应变和孔隙的形态参数.根据等效本构方程和能量守恒方程,获得孔隙介质承受载荷作用下的应力应变关系.最后将该力学模型应用于水泥基材料,计算水泥基材料的力学性能并与文献中的结果进行对比分析,结果显示模型的计算结果准确有效.

A new mechanical model is established in this paper on the basic theories of fracture mechanics and meso-mechanics. The mechanical properties of porous media are analyzed. Based on the geometric descriptions and morphological parameters of the pores in porous media such as porosity, shapes and scales, effective elastic equation can be established by equivalent inclusion theory. The final variables of effective elastic equation are stress, strain and morphological parameters of the pores. Mechanical energy, elastic strain energy and potential energy of the porous media are calculated and the energy conservation equation is established. The final variables of energy conservation equation are also stress, strain and morphological parameters of the pores. So the stress-strain relationship of porous media can be obtained by the two equations. Applying the mechanical model in cement material, the mechanical properties can be calculated. The results obtained are consistent with conclusion of the literatures.