摘要:对于作用点位置随时间连续变化的移动荷载,本文采用精细积分法求解桥梁结构动力平衡方程,用Hermite插值函数模拟节点等效荷载,并推导出常量移动荷载在任意时间步长内的Duhamel积分格式,包括时间步长的开始和结束时刻集中荷载分别在同一个单元、相邻单元和不相邻单元三种情况。数值算例表明,即使采用最大时间步长,本文提出的方法仍可求得高精度数值解,与其它数值方法比较具有明显优势。
Abstract:In this paper,precise-time step integration method is used to solve the dynamic equation of bridge under moving loads.The moving property of moving load is simulated as equivalent joint loads by Hermite function.The Duhamel integration format of moving load during a time interval is derived,including the moving load at the start time and at the end time on the same element,neighboring elements,or non-neighboring elements.Numerical example shows that highly accurate solution from the proposed method can be obtained by maximum time step in comparison with other numerical methods.