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为较准确反映岩体工程在地震荷载下的响应,结合Drucker-Prager屈服准则和次加载面理论,初步构建基于Drucker-Prager准则的次加载面应力路径模型,在此基础上,除计算弹性模量的率效应之外,还在Drucker-Prager准则上考虑强度的率效应,提出岩石材料的动态模型,并把该模型运用到滇中引水香炉山隧洞中。计算结果表明,相对于Drucker-Prager准则,应力路径模型能较好地描述玄武岩在循环荷载下体现的曼辛效应和棘轮效应,由于没有考虑率效应,表现出应力–应变曲线的斜率没有试验曲线大,且累计应变也比试验曲线大;在岩石循环加卸载过程中,动态模型得出的模量上比次加载面应力路径模型模拟的要大,同时变形量也较次加载面应力路径模型要小,因此该模型能较好地反映岩石的动态力学性质和变形性质;相比于Drucker-Prager准则下,采用动态模型得出隧洞的左侧监测点和右侧监测点的瞬时相对变形峰值增大了0.67 cm,同样底部和顶部以及左右两侧的永久相对变形也分别增大了0.19和0.77 cm,说明动态模型可以较好地反映围岩残余大变形;岩石动态模型相对于Drucker-Prager准则和线弹性本构,更具有滤掉高频的功能。说明该模型能很好地运用到岩石动力学中,同时也为准确分析岩体工程在地震作用下的响应奠定了一个很好的基础。
Based on Drucker-Prager yield criterion and sub-loading surface theory, the sub-loading surface stress path model based on Drucker-Prager criterion was constructed to reflect the response of rock mass engineering under seismic load accurately. Based on this, except calculating elastic modulus In addition, the Drucker-Prager criterion is used to consider the rate effect of strength, and a dynamic model of rock material is proposed. The model is applied to the tunnel of Xiangluo Mountain in the middle Yunnan. The results show that, compared with the Drucker-Prager criterion, the stress path model can well describe the Manning effect and the ratcheting effect of basalt under cyclic loading. Since the rate effect is not considered, the slope of the stress-strain curve shows no experimental curve Large, and the cumulative strain is also larger than the experimental curve. During the cyclic loading and unloading process, the dynamic model has a larger modulus than the secondary loaded surface stress path model, and the deformation is also less than that of the secondary loaded surface stress path model So the model can better reflect the dynamic mechanical properties and deformation properties of the rock. Compared with the Drucker-Prager criterion, the dynamic model is used to obtain the instantaneous relative deformation peaks of the left monitoring point and the right monitoring point of the tunnel 0.67 cm, 0.67 cm and 0.77 cm for the same bottom, top and left and right sides, respectively. This indicates that the dynamic model can well reflect the large residual deformation of surrounding rock. The dynamic model of rock relative to Drucker-Prager Criteria and linear elastic constitutive, but also has the function of filtering out high frequency. It shows that the model can be well applied to rock dynamics and also provides a good foundation for accurate analysis of the response of the rock mass under earthquake action.