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一般岩石块体中包含若干孔隙,孔隙中含有不同的流体.孔隙和流体对岩块的弹性特性有较大的影响.本文构建了一种“岩石胞元”,该胞元由一个孔隙流体夹杂和岩石基体组成.基于Eshelby等效夹杂原理推导出岩石胞元的等效弹性常数张量的表达式.当岩石胞元的孔隙占比与岩块孔隙率相等时,则岩石胞元布满岩块,此时岩块等效弹性常数与岩石胞元的弹性常数相等.当孔隙占比大于岩块孔隙率时,岩石胞元总体积小于岩块体积,岩块等效为岩石胞元和岩石基体的组合体,此时岩块的等效弹性常数为两者弹性常数的体积加权平均值.分析表明,岩石胞元的孔隙占比取值与岩块基体和孔隙流体的特性密切相关,可由试验确定;岩块等效弹性模量随着孔隙率的增大而减小,随着孔隙流体夹杂弹性模量的增大而增大.本文岩块弹性常数估计结果与已有理论和试验结果进行了比较,具有较好的一致性.“,”Rock block contains many pores generally.The pores include the different fluid inclusions.The pores and the fluid inclusions have obvious influence on the elastic property of the rock block.The paper built a ‘rock-cell’ composed of one pore fluid inclusion and rock matrix around the pore.The expression of equivalent elastic constant tensor of the rock-cell is derived based on Eshelby’s inclusion theory.If the volume ratio of pore vs rock-cell is equal to the rock porosity,the rock block is covered with rock-cells and the block equivalent elastic constant is equal to the rock-cell elastic constant.If the volume ratio of pore vs rock-cell is greater than the porosity,the volume of overall the rock-cells is smaller than the block volume.The rock block can be equivalent to the combination of rock-cells and rock matrix.The rock block equivalent elastic constant is the volumetrically weighted average of the two elastic constants.The results indicate that the valuation on volume ratio of the pore vs the rock-cell is correlated to the characteristics of rock matrix and pore fluid,and it can be determined by experiment;The block equivalent elastic modulus decreases with the porosity increasing and increases with the pore fluid inclusion elastic modulus decreasing.The results estimating rock block elastic constant using this method is a good agreement with the existing theory and the experiment data.