【摘要】 模态试验是桥梁结构试验考核的重要内容之一,试验获得的模态参数对验证结构设计、建立结构的动力学模型以及使用状态的评估均具有重要意义。传统的模态试验方法是采用人工激励法进行激振,但对于大跨度钢桥无论是实施人工激励还是测试外部激励都是困难的。为此,采用基于环境激励的谱分析方法对某型大跨度钢桥进行了模态测试与分析,并对测试设备、传感器、分析软件作必要的配置与完善,给出了某型大跨度钢桥空载状态下的阵型及相应的固有频率,为同类装备的模态试验及振动特性分析提供了参考。更多还原

【Abstract】 modal test is one of the importance content of the bridge test,and the modal parameters from the testing are great significance for structural design validation,dynamics model constitution and bridge condition assessment.The traditional methods of modal test is base on artifical excitation,but it is difficulty to exert artifical excition on Long span steel Bridge or measure the exterior excition of Long span steel Bridge.In order to solve these problem,the modal test method based on environment excitation is used,and the modal test of the Long span steel Bridge is completed by configuring the test equipment sensors and analytic software.Through the testing data analysis,it educed the mode shapes and natural frequencie.All of these provide reference for modal test of similar equipment.更多还原