基于响应面法的复式钢箱提篮拱地震可靠度分析

Seismic Reliability Analysis of the Basket-handle Arch Based on the Response Surface Method

地震可靠度是桥梁抗震研究中的重要问题。基于随机分析的响应面理论和规范反应谱法,提出了一种分析具有随机结构参数的桥梁地震可靠度的方法,研究了复式钢箱提篮拱桥在地震激励下,结构设计基准期内的可靠度。分析时考虑了结构参数和场地土的随机性,分别计算了钢箱提篮拱桥主、副拱肋在多遇地震、设防地震和罕遇地震作用下的失效概率,得到了主、副拱肋在设计基准期内,按规范"三水准设防标准"条件下的地震可靠度。计算结果表明,该桥设计满足抗震规范要求。

Seismic reliability is very important to the seismic design of the bridge. Based on theory of the response surface of random vibration and response spectral method, an algorithm for the seismic reliability analysis of the structure with random parameters is proposed in this paper. The seismic reliabilities of the basket-handle arch subjected to seismic excitation in its design basic period are studied. The random of the structure parameters and the site condition of this bridge are taken into account when the arch fibs＇ failure seismic reliabilities are computed respectively at the low-level earthquake, design earthquake and high-level earthquake. According to the ＂three-level seismic fortification criterion＂ in the code for seismic design of bridge, the seismic reliabilities of the arch ribs are calculated in their design basic period. The conclusion shows that the design of this bridge meets the demands of the seismic code.