联合整体和局部动态信息的空间桁架模型修正试验

由于土木工程结构的复杂性、传感器测点的有限性以及局部损伤的不敏感性等问题，大型结构的模型修正存在一定困难。针对空间桁架结构，为克服上述问题，对其进行整体和局部的动力测试试验，然后联合实测的结构整体和局部动态信息进行模型修正：首先进行空间桁架整体的动力测试试验，获得反应整体特性的低阶模态；然后为了提高局部杆件的动态特性，在杆件上附加一定质量，获得附加质量后杆件的局部主频率，并在各类杆件中选取一定数目进行动态测试；最后联合所有实测结构整体的低阶模态和杆件的局部主频率，对空间桁架结构进行模型修正。修正后的模态参数与实测模态吻合良好，验证了方法的有效性。

The model updating experiment of space truss using global and local dynamic information

For large structures in civil engineering, due to their complexity, the limitation of the sensors and insensitivity to the local damage, the model updating is hard to be performed accurately. Aiming overcoming the above problems, in the model updating of a space truss structure, it performs the global and local dynamic tests , and both the measured global and local dynamic information are combined and used for the truss model updating. First the global test is made to obtain the low order modes which reflect the global information of the structure; then certain mass is added on the truss element to increase the local dynamic characteristic of truss element and to make the element have local primary frequency, which is mainly determined by the element stiffness; finally, all the experiment data, including low mode and local primary frequencies, are combined and used for modal updating. The effectiveness and accuracy of the proposed method is verified by the experiment.