超长斜拉索张力振动测量的传递矩阵法  

Transfer Matrix Method for Vibration Measurement of Super Long Stay Cable Tension

作　　者：刘志军[1] 芮筱亭[1] 展志焕[1] 冯宾宾[1] 王国平[1] 

机构地区：[1]南京理工大学发射动力学研究所,南京210094

出　　处：《振动．测试与诊断》2012年第4期634-639,692,共6页Journal of Vibration,Measurement & Diagnosis

基　　金：江苏省自然科学基金攀登计划资助项目(编号:BK2008046);国家自然科学基金资助项目(编号:10902051)

摘　　要：振动法测量拉索张力需要准确描述索力与自振频率的关系,为反映超长斜拉索的真实构形及垂度效应,满足超大跨斜拉桥对测试精度的要求,考虑超长斜拉索垂度、倾角、自重及切向张力沿拉索变化的影响,在静力分析推导出斜拉索静态构形的悬链线方程基础上建立超长斜拉索振动的离散模型,应用多体系统传递矩阵法计算拉索固有频率,通过求解特征方程建立索力与振动频率的关系,提高了超长斜拉索张力的振动测量精度,完善了索力振动测量方法。通过对实际工程的测试结果分析表明,该方法具有准确、实用和易编程的特点,完全能满足工程应用要求。The relation between cable tension and natural vibration frequencies needs to be defined accurately for measurement of cable tension by vibration method. It is necessary to express the geometric shape of supper long stay cable exactly and consider sag in order to meet the demand of measurement accuracy for super long-span cable-stayed bridge. The cable-vibration discrete model is established on the base of the catenary equation for static profile of stay cable developed by static analysis with the consideration of cable sag, inclination angle, self-weight and variation of cable tension along the cable. Transfer matrix method of multibody system is used to compute natural vibration frequencies of cable based on the discrete model. The relation between cable tension and natural vibration frequencies is described by solving characteristic equation. The measurement accuracy of super long stay cable tension is improved and the vibration method for measurement of cable tension is further perfected. The field measurement results are analyzed and it is indicated that the proposed method has high computational efficiency because of low order of system matrix and can effectively satisfy the requirements for measurement accuracy of cable tension.

关 键 词：传递矩阵法 超长斜拉索 索力 固有频率 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]