框架预应力锚杆挡墙的系统可靠性分析

将立柱视为连续梁，锚杆视为固定或弹性支座，土压力荷载视为梯形分布，基于矩阵位移法与Matlab的符号函数求解功能，编制锚杆和立柱内力的求解程序。视锚杆的失效为脆性破坏与延性破坏的中间状态，分别按脆性破坏与延性破坏计算锚杆体系失效概率的上下限。对工程实例的计算结果表明，若将锚杆视为脆性结构，当其中一根锚杆破坏后其邻近锚杆失效概率迅速增加，最大增幅近12倍，验证脆性构件组成的超静定结构可视为串联系统；然后基于各根锚杆功能函数之间的相关系数矩阵，得到脆性破坏时锚杆体系失效概率的上限。最后，以立柱上所有锚杆同时达到极限状态的理想状态构建锚杆体系延性破坏时的功能函数，得到其失效概率的下限。

SYSTEM RELIABILITY ANALYSIS OF FRAME PRESTRESSED ANCHOR BOLT

The post is considered as a continuous beam，anchor bolt as fixed or elastic support，the soil pressure load as a trapezoid distribution，based on the matrix displacement method and the Matlab symbol function for function，elastic support continuous beam internal force calculation program is compiled. Treating the bolt failure as the intermediate state of brittle fracture and ductile fracture，the limits of bolt system failure probability according to the brittle failure and continuity failure is calculated. The calculation results of an engineering example show that，if the bolt as the brittle structure，when one of the adjacent anchor bolt failure probability of failure increases rapidly，the maximum amplitude is as high as 12 times，verifing the brittle structure composed of statically indeterminate structure can be considered as a series system. Then brittle fracture bolt system failure probability upper bound based on the anchor bolt function correlation coefficient matrix is obtained. At last，function of ductile failure of anchor system is put forward based on the ideal state of the all bolts on the column reach the limit state at the same time，and the lower limit of failure probability is got.