【摘要】 考虑结构参数随机性的动力可靠度是桥梁抗震研究中的重要问题。本文基于随机分析的响应面理论和规范反应谱方法,提出一种分析具有随机结构参数桥梁抗震可靠度的方法。通过拟合的多项式函数来近似替代表示结构随机输入与输出变量之间作用关系的功能函数,按照结构的破坏准则及其极限状态方程,进行可靠度分析。运用该方法研究高墩大跨连续刚构桥在地震激励下设计基准期内的动力可靠度,分析时考虑结构参数和场地土的随机性,分别计算连续刚构在多遇地震、设防地震和罕遇地震作用下的失效概率,得到结构在设计基准期内,"三水准设防标准"条件下的地震可靠度。结果表明,该桥设计满足抗震规范要求。更多还原

【Abstract】 Dynamic reliability of the structures with random parameters is very important to the anti-seismic design of bridges.Based on the theory of the response surface of random vibration and response spectral method,an algorithm for the anti-seismic reliability analysis of the structure with random parameters is proposed.The response surfaces generally take an approximate polynomial form to replace the function which denotes the relationships of the input random parameters and the output parameters.The reliabilities are studied according to structural failure criterions and the equations under their limit states.The anti-seismic reliabilities of the high-pier long-span continuous rigid frame subjected to seismic excitation in its design base period are studied by this method.The random of the structure parameters and site conditions of this bridge is taken into account when the failure probabilities of anti-seismic reliabilities are computed respectively for the frequently-occurring low-level earthquake,resistance-designed earthquake and rarely-occurring high-level earthquake.According to the "three-level anti-seismic criterions" in the code for anti-seismic design of bridges,the anti-seismic reliabilities of the bridge are calculated for their design base period.The conclusion shows that the design of this bridge meets the demands of the anti-seismic code.更多还原