结构多轴抗震试验加载系统开发及控制策略研究

Multi-axial dynamic structural testing system and its control strategies

开发基于液压伺服作动器的高性能三自由度结构动力试验加载系统,该系统特点为控制精确、功能全面。建立力控制下位移加载混合控制方法,提出拟静力试验中多作动器耦合控制策略。以足尺钢结构立柱为试件,研究应用三自由度结构动力试验系统进行拟静力试验与混合试验具体方法,验证该试验系统在结构动力试验中应用的可行性、有效性。结果表明,通过对多作动器的耦合控制,该试验系统可在拟静力试验中同时实现对立柱试件恒定的竖向力控制及精确剪切型加载。通过基于α-OS法的混合试验证明该加载系统可精确模拟单柱子结构复杂边界条件,对整体坐标与作动器局部坐标变换,可实现多作动器位移协调加载。该结论可推广至多自由度试验系统研究中。

A high-performance 3 Degrees of Freedom Dynamic Structural Testing System （3DOFs testing system） which is mainly built with MTS servo-hydraulic system was developed.Its prominent advantages are accurate control and comprehensive function.A two-loop feedback control strategy was introduced and extended to multiple actuators＇ coupled control.To demonstrate the performance of the proposed testing system and control strategies,a full-scale steel column was taken as a test specimen.It is concluded that,by using the coupled control strategy,the testing system can perform perfectly in quasi-static test,vertical force can be kept constant,and shear-mode loading can be achieved simultaneously. Furthermore,by applying α-OS method in hybrid test,it is proved that the 3DOFs testing system can accurately simulate the complex boundary conditions of column substructure,and the harmonious loading of multiple actuators can be successfully implemented.The results may give references to further studies on multi-axial testing system.