混凝土喷层支护节理岩体等效力学模型及其应用

Equivalent mechanical model of joined rockmass reinforced by shotcrete lining and its application

考虑喷层在节理面局部的限剪和限裂作用,提出喷层支护节理岩体流变模型,在此基础上推导出喷层支护节理岩体的本构关系,建立了一种喷层支护节理岩体等效力学模型。采用该模型进行结构有限元计算,喷层、节理均不需要离散网格,进行等效模拟;当实际节理裂隙的数量与方向或喷层的厚度变化时,也不需要变化计算网格,从而可降低前处理工作量,为大型复杂结构的计算分析提供较大便利。最后,通过算例和实际工程验证了该模型的有效性——不仅具有离散模型便于模拟喷层真实作用机制的优点,而且具有等效模拟简单易行的优点,具有较好的工程应用前景。

A rheological model of equivalent simulation has been presented by considering the lining＇s action of controlling shear and crack on joints and fractures; and on this base, the constitutive equation of jointed rock mass reinforced by shotcrete lining has been deduced; so the equivalent mechanical model of jointed rock mass reinforced by shotcrete lining has been established. When a structure is analyzed by using this mechanical model, joints or shotcrete linings need not to be discreted grids, and are equivalently simulated. If the number and direction ofj oints or the thickness of shotcrete lining are changed in the analysis of structures, the finite element mesh will keep unchanged. In this way, the pre-treatment workload is reduced and the analysis of the large scale rock structures becomes relatively convenient. Finally, this mechanical model has been verified by examples--not only effective in the simulation of the mechanism of shotcrete lining similar to discrete model, and convenient and practical for the complicated structures similar to equivalent simulation; it will be of good practical application.