论文部分内容阅读
围岩支护结构稳定性是地下结构设计的关键。针对深部隧道围岩参数信息统计不足,引入Information-gap理论,建立支护围岩结构非概率可靠性分析方法。给出了无量纲不确定水平参数的Info-gap模型,根据系统模型和性能要求得到可靠度分析的稳健函数,并将结构发生失效前能够容许的不确定参量的最大波动幅值作为稳健可靠度指标。结合剪切滑移线场理论,推导了均质弹塑性围岩最优支护阻力,建立围岩支护结构稳定分析的响应函数。实例工程展示了稳健可靠度分析的具体操作程序。参数分析表明,支护阻力越大,结构越稳健性;同时,提高巷道围岩的内摩擦角和黏聚力是增加支护结构稳健性的关键。该方法在参数信息少、样本数据有限情况下,是处理不确定问题的一种合理有效方法。
Surrounding rock support structure stability is the key to the design of underground structures. In view of the lack of statistic information of surrounding rock parameters in deep tunnels, Information-gap theory is introduced to establish the non-probabilistic reliability analysis method of surrounding rock mass. The Info-gap model with dimensionless uncertain level parameters is given, and the robust function of reliability analysis is obtained according to the system model and performance requirements. The maximum fluctuating amplitude of the uncertain parameters that can be tolerated before the structure failure is taken as the robust reliability index. Combined with the theory of shear slip line field, the optimal support resistance of homogeneous elastic-plastic surrounding rock is deduced and the response function of stability analysis of surrounding rock supporting structure is established. The example project shows the specific operating procedures for robust reliability analysis. The parameter analysis shows that the larger the support resistance, the more robust the structure. Meanwhile, increasing the internal friction angle and cohesion of the surrounding rock is the key to increase the robustness of the support structure. The method is a reasonable and effective method to deal with the uncertain problem under the condition of limited parameter information and limited sample data.