地下洞室群面向对象有限元方法的探讨

以单元为代表类简单介绍了地下洞室群面向对象有限元程序。利用自编的面向对象有限元程序实现了开挖模拟,并分析某地下厂房的分步开挖变形问题,其结果与Phase2软件计算结果基本一致;实现了面向对象有限元处理动力响应的人工边界输入问题,验证了其正确性,并对该地下厂房的动力响应规律进行了探讨。结果表明:监测点响应存在一定的滞后性,且峰值的放大系数比无洞室作用下的理论解要大;在此基础上,分析了不同方法下的阻尼系数对地下洞室群动力响应的影响;验证了面向对象有限元方法应用在地下洞室群中的可行性和适用性。研究成果为进一步研究动态弹塑性情况奠定了基础。

Discussion on the Application of Object-Oriented FEM to Underground Caverns

Object-oriented FEM program of underground caverns is briefly introduced with class element as repre-sentative.A program code written in VC + +is presented to simulate the stepped excavation of an underground powerhouse and to analyse the deformation.The result is consistent with that of Phase2 software.The seismic input in dealing with dynamic response is implemented through artificial boundary by using object-oriented FEM.Further-more,the law of dynamic response of the underground powerhouse is analysed and the result shows that the re-sponse of monitoring points lags behind and the amplification factor of peak is larger than theoretical solution in the absence of cavern under the same action.On this basis,the influence of damping coefficient on the dynamic re-sponse of underground caverns by different methods is researched.The feasibility and applicability of object-orien-ted FEMin underground caverns are validated.The research result lays a foundation for further study on elastic-plastic behavior under dynamic load.