基于复模态随机响应的钢筋混凝土梁桥抗震可靠度分析  

Seismic Reliability Analysis of Reinforced Concrete Beam Bridge Based on Complex Mode Random Response

作　　者：张振浩[1,2] 杨伟军[1] 

机构地区：[1]长沙理工大学土木与建筑学院,湖南长沙410076 [2]桥梁工程安全控制技术与装备湖南省工程技术研究中心(长沙理工大学),湖南长沙410076

出　　处：《桥梁建设》2014年第1期69-74,共6页Bridge Construction

基　　金：国家自然科学基金资助项目(51108044);长沙理工大学桥梁工程安全控制技术与装备湖南省工程技术研究中心开放基金资助项目(12KC03)~~

摘　　要：对于非经典阻尼、非对称质量和非对称刚度的非对称梁桥结构,其振动方程难以解耦,为便于求得此类结构抗震可靠度分析时振动方程的解析解,引入复模态变换,求得结构在地震作用下的复模态响应,进而求解响应过程超越安全界限的概率而获得结构抗震可靠度,并通过算例进行了验证。结果表明,采用复模态分析法易于获得关于复模态响应的已解耦方程,且该方程通常具有简洁的脉冲响应函数矩阵,容易求得结构随机地震响应的解析解,计算精度也较高;算例计算验证了基于复模态随机响应的钢筋混凝土梁桥抗震可靠度分析方法是合理可行的。For the asymmetric bridge structure characterized by the nonclassic damping, asymmetric mass and asymmetric rigidity, the vibration equation for the structure is difficult to be decoupled. To easily acquire the analytical solution to the vibration equation in the seismic reli ability analysis of such type of the structure, the complex mode transformation was introduced and the complex mode response of the structure under the seismic action was solved. The proba bility of the response process exceeding the safety margin was continuously solved, the seismic reliability of the structure was acquired and the solving process was then verified by the calcula tion examples. The results of the solving calculation indicate that the decoupled equation related to the complex mode response can be easily acquired, using the complex mode method and gener ally, the equation has the simple impulse response function matrix and with the equation, the an alytical solution to the random seismic response of the structure can be easily acquired. The calcu lation precision of the equation is high and the seismic reliability analysis method for the rein forced concrete beam bridge based on the complex mode random response also proves to be reasonable and practicable through verification of the calculation examples.

关 键 词：钢筋混凝土结构 简支梁桥 桥梁抗震 可靠度分析 复模态 随机响应 计算方法 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]