考虑损伤作用计算多孔介质有效应力研究

DAMAGING EFFECTIVE STRESSES OF POROUS MEDIA

多孔介质的变形表现为黏弹塑性,其中,弹性变形体现为本体变形;黏性变形体现为结构变形;塑性变形体现为损伤变形.在原有有效应力理论的基础上结合损伤力学的基本原理,研究多孔介质有效应力的性质.在原假设多孔介质颗粒可压缩的前提下,假定部分颗粒可发生局部破坏,并且在颗粒破坏后,有效应力将有所增加,相应的骨架承载能力将有微小程度增强.采用损伤有效应力参与计算将能更加准确地描述多孔介质复杂的变形性质.

The deformation of porous media is visco-elasto-plastic,with the elastic deformation as the mainbody deformation,the viscous deformation as the structure deformation and the plastic deformation as the damage deformation.Based on the concept of effective stresses and the principle of damage mechanics,this paper studies the properties of effective stresses of porous media.Assuming that the grain is in compression, and the grains can have a local failure,with an increase of the effective stresses and the supporting capacity of grains,the damage effective stresses are considered in the calculation,which would show the complex properties of deformation of porous media more accurately.