预应力锚杆复合土钉支护稳定可靠度分析

发布时间：2018-09-12 05:12

【摘要】：针对预应力锚杆复合土钉支护结构的稳定可靠性分析问题,以极限平衡理论为基础,建立了基坑稳定性分析安全系数求解公式和可靠性分析功能函数。以土体力学参数为作为随机变量,应用Monte Carlo重要抽样法计算了基坑稳定性可靠度指标和失效概率,通过工程实例进行了分析。分析表明:该稳定性计算公式计算的安全系数符合工程要求并且通过可靠性分析,因而使用该方法对复合土钉支护结构稳定性计算是有效的;基坑可靠性分析中,可靠度指标?和失效概率Pf受土体黏聚力、内摩擦角与摩阻力的变异系数的影响较大,前者随变异系数的增大而减小,后者随变异系数的增大而增大;对于土体力学参数分布选型参数c采用对数分布,φ、qsik采用正态分布对可靠度计算分析比较合理。
[Abstract]:Aiming at the problem of stability and reliability analysis of prestressed anchor composite soil nailing structure, based on the limit equilibrium theory, the formula for calculating the safety factor of foundation pit stability analysis and the function for reliability analysis are established. Taking soil mechanics parameters as random variables, the reliability index and failure probability of foundation pit stability are calculated by using Monte Carlo important sampling method, and an engineering example is used to analyze the reliability index and failure probability of foundation pit. The analysis shows that the safety factor calculated by the formula meets the engineering requirements and through reliability analysis, so it is effective to calculate the stability of composite soil nailing structure by using this method, and the reliability index of foundation pit reliability analysis. And the failure probability Pf is greatly affected by the cohesive force, the angle of internal friction and the coefficient of variation of friction resistance. The former decreases with the increase of coefficient of variation, and the latter increases with the increase of coefficient of variation. For the distribution of soil mechanical parameters, the logarithmic distribution is adopted for the selection parameter c, and the normal distribution for 蠁 QSik is used to calculate and analyze the reliability.
【作者单位】：兰州理工大学甘肃省土木工程防灾减灾重点实验室;兰州理工大学西部土木工程防灾减灾教育部工程研究中心;
【基金】：国家科技支撑计划项目(2011BAK12B07) 兰州理工大学建工七七基金项目(TM-QK-1304) 兰州理工大学博士基金项目
【分类号】：TU476

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