论文部分内容阅读
将顺层岩质边坡的层面考虑为弱面,将其等效为等间距共线多节理的力学模型。预应力锚索加固边坡的锚固模型等效为平面有限宽度岩体节理问题。并将初始应力和地震荷载引起的附加动应力视为远场作用,锚固边坡的受力问题视为远场作用效果和节理面集中力作用效果的叠加。根据叠加原理计算地震荷载作用下裂纹端部应力强度因子,发现位于裂纹端部的预应力锚索能大幅度降低I型裂纹的应力强度因子。以应力强度因子作为岩体的压剪破坏判据解释顺层岩质边坡预应力锚索的抗震加固机制,能很好地解释汶川地震边坡破坏特点。
Considering the bedding rock slope as a weak surface, it is equivalent to the mechanical model of equidistance and collinear multi-joint. The anchoring model of prestressed anchor reinforcement slope is equivalent to the problem of rock mass joint with finite width. The additional dynamic stress caused by initial stress and earthquake load is regarded as the far-field effect. The problem of the anchorage slope force is regarded as the superposition of the far-field effect and the concentrated effect of the joint surface. According to the principle of superposition, the stress intensity factor at the crack tip under seismic load is calculated. It is found that the prestressed anchor cable located at the crack tip can significantly reduce the stress intensity factor of type I crack. Taking the stress intensity factor as the criterion of the pressure-shear failure of rock mass to explain the seismic strengthening mechanism of the prestressed anchor cable of the bedding rock slope, the failure characteristics of the Wenchuan earthquake slope can be well explained.