层间作用对复合岩石单轴抗压强度的影响研究

6Theoretical study on uniaxial compressive strength of composite rock considering interlayer interaction

为研究岩石层间作用对复合岩石单轴抗压强度的影响,基于直线型莫尔强度准则、格里菲斯准则和德鲁克-普拉格准则,开展复合岩石单轴抗压强度研究。通过分析岩石层间作用,得到层间作用影响下的3种复合岩石单轴抗压强度计算理论模型,并对理论模型进行实验验证。结果表明:(1)岩石层间作用对复合岩石单轴抗压强度影响明显,无论静力平衡状态还是滑动平衡状态,层间作用均会降低高强度岩石强度,增加弱强度岩石强度;(2)各组分岩石层间作用效应受各组分岩石的弹性模量、泊松比、内摩擦角和黏聚力影响;(3)对比理论计算结果与实验结果,直线型莫尔强度准则计算模型误差仅为4%,格里菲斯准则的计算模型误差为113%,德鲁克-普拉格准则的计算模型误差为63%,采用直线型莫尔强度准则计算复合岩石单轴抗压强度最为准确。

The influence of interlayer interaction on the uniaxial compressive strength of composite rock is significant.Based on linear Mohr strength criterion,Griffith criterion and Drucker Prague criterion,the uni‐axial compressive strength of composite rock is studied.Based on the analysis of interlayer interaction of rock,three kinds of uniaxial compressive strength calculation models of composite rock considering the in‐fluence of interlayer interaction are obtained,and the theoretical models are verified by experiments.The re‐sults showed that:(1)The interlayer interaction has a significant effect on the uniaxial compressive strength of composite rocks.The interlayer interaction can reduce the strength of high strength rocks and increase the strength of weak strength rocks in both static equilibrium and sliding equilibrium states.(2)The interlayer interaction is affected by the elastic modulus,Poisson′s ratio,internal friction Angle and cohesion of each component rock;(3)Comparing the theoretical calculation results with the experimental results,the calcula‐tion model error of linear moire strength criterion is only 4%,the calculation model error of Griffith crite‐rion is 113%,and the calculation model error of Drucker Prager criterion is 63%.The linear Moire strength criterion is the most accurate to calculate the uniaxial compressive strength of composite rock.