钢管混凝土拱桥拱肋模型修正方法研究  

Resrach of a Model Updating Method for Arch Rib of CFST Arch Bridge

作　　者：谢开仲 覃乐勤[2] 吕文高[2] 

机构地区：[1]同济大学桥梁工程系,上海200092 [2]广西大学土木建筑工程学院,广西南宁530004

出　　处：《桥梁建设》2010年第3期24-28,共5页Bridge Construction

基　　金：广西科学研究与技术开发计划项目(桂科攻0816006-7)

摘　　要：由于荷载或环境因素,在役钢管混凝土(CFST)拱桥的实际状态与新建时的状态存在差异,针对钢管混凝土拱桥主要受力部分钢管混凝土拱肋,提出基于共轭梯度法并结合空间曲率模态差对其计算模型进行修正的方法。通过对一个单圆管钢管混凝土拱肋的模型修正,验证该方法的有效性。结果表明:基于曲率模态和固有频率的目标函数比基于曲率模态的目标函数修正效率高了1倍;目标函数取前2阶曲率模态的修正精度明显高于取1阶曲率模态的修正精度,损伤区域越多越明显;损伤区域越多,修正精度越低,需要的模态阶数越高;该方法不仅可以对模型进行修正,还可用于损伤识别和诊断。Owing to the factors of load or environment,the actual conditions of an in-service concrete-filled steel tube（CFST） arch bridge can be different from the conditions of the bridge that is newly built.In the light of the principal load-carrying part,the CFST arch rib of the bridge,an updating method for the calculation model of the arch rib based on the conjugate gradient method and spatial curvature mode difference is proposed and the effectiveness of the method is verified through updating of a model of a single round tube CFST arch rib.The results reveal that the updating efficiency of the objective function based on the curvature mode and natural frequency has increased 1 time as compared to that of the objective function only based on the curvature mode.The updating precision of the objective function using the first 2 orders of the mode is obviously higher than that of the objective function using only 1 order of the mode.The more the damaged areas are,the obvious the situation will be,the lower the updating precision will be and more orders of the mode will be required.The updating method herewith can be not only used for the model updating,but also for the damaged area identification and diagnosis.

关 键 词：拱桥 钢管混凝土结构 拱肋 模型修正 共轭梯度法 优化算法 曲率模态差 

分 类 号：U442.5[建筑科学—桥梁与隧道工程]