分布载荷作用下结构整体动力响应估计  

Estimation of Overall Dynamic Response of Structure under Distributed Loads

作　　者：谢远春 Xie Yuanchun

机构地区：[1]南方科技大学海洋科学与工程系,518055

出　　处：《工程机械》2022年第6期12-22,I0017,I0018,共13页Construction Machinery and Equipment

摘　　要：工程中大量结构受到的环境载荷多为分布载荷,基于现有的Kalman滤波Joint input-state estimation算法,提出利用模态等效力进行分布载荷作用下结构的整体响应估计新思路,该方法不需要了解载荷的具体分布形式和载荷大小,在结构的有限元模型基础上,将实际外载荷等效为模态空间的多个模态力,利用经典的Kalman滤波迭代步骤实现系统状态和载荷的最小方差无偏估计,从而实现结构全局响应估计。为了满足系统的稳定性、可观性、可控性和可逆性条件,提出7步使用该算法的规范性流程,实现对相关参数的选择。利用ANSYS对两种分布载荷情况下悬臂梁进行数值计算,用提出的流程对算法进行验证,数值验算结果体现了算法的可靠性。由于工程中大量结构可以等效为梁单元和梁单元的组合形式,该方法及数值算例对工程实践具有一定的指导意义。Most of the environmental loads on a la rge number of structures in enginee ring are distributed loads.Based on the existing Kalman filter Joint input-state estimation algorithm,a new idea of using modal equivalent force to estimate the overall response of the structure under distributed loads is proposed.This method does not require knowledge of the specific distribution form and size of the load.On the basis of the finite element model of the structure,the actual external load is equivalent to multiple modal forces in the modal space,the classical Kalman filter iteration step is used to realize the minimum variance unbiased estimation of the system state and load,thereby achieving the global response estimation of the structure.In order to meet the conditions of stability,observa bility,co ntrollability and reve rsibility of the system,a 7-step normative process using the algorithm is proposed to realize the selection of relevant parameters.The cantilever beam under two distributed loads is numerically calculated by ANSYS,and the algorithm is verified by the proposed process.The numerical verification results ref ect the reliability of the algorithm.Since a la rge number of structures in enginee ring can be equivalent to the combination of beam element and beam element,the method and numerical examples have certain guiding significance for engineering practice.

关 键 词：KALMAN滤波 动力响应 分布载荷 有限元 

分 类 号：TU312.1[建筑科学—结构工程]