论文部分内容阅读
分析了抗力服从不同先验分布时其后验分布的数字特征变化规律,建立了验证荷载条件下的抗力概率模型;结合条件概率的方法,建立了验证荷载条件下的结构可靠指标计算公式。并从验证荷载前后结构功能函数相关系数、验证荷载取值等方面对一实例桥梁进行了可靠度分析,同时研究了恒载参数、活载参数对考虑验证荷载的既有桥梁结构可靠度的影响。结果表明,已服役期的验证荷载对桥梁结构可靠指标的影响不能忽视,考虑验证荷载,时既有桥梁结构可靠指标比不考虑验证荷载时要大;同一验证荷载,当验证荷载前后结构的功能函数为高级相关时,结构可靠度增长幅度大;考虑验证荷载时,既有桥梁结构可靠度随着恒载及活载变异系数的增大而递减。
The change rule of digital features of posterior distribution when the resistances are subject to different prior distributions is analyzed, and the resistance probability model under the condition of the verification load is established. Combining with the conditional probability method, the calculation formula of the structure reliability index under the condition of the verification load is established. The reliability of an example bridge is analyzed from the correlation coefficient of structural function before and after the verification of load and the value of verification load. Meanwhile, the influence of the parameters of dead load and live load on the reliability of existing bridges considering the verification load is studied . The results show that the validated load of service period can not ignore the influence of the reliability of the bridge structure. Considering the verification load, both the reliability index of the existing bridge structure is larger than that when the verification load is not considered. When verifying the load, When the function is advanced, the degree of structural reliability increases greatly. When the verification load is considered, the reliability of the existing bridge structure decreases with the increase of the constant load and the variation coefficient of live load.