将Newmark法中常平均加速度法的基本假定与更新精细积分方法结合起来,提出了一种新精细积分法,并应用于结构的地震反应分析中.推导了该方法的计算公式,对其稳定性进行了分析.与更新精细积分法相比,在实现动力微分方程降阶后,矩阵尺度和方程个数减少一半;并且迭代公式直观,可以非常方便地求出结构在地震作用下的位移、速度和加速度反应.提出的方法虽然是条件稳定的,但是其稳定性条件极易满足.算例表明方法的有效性及对地震作用的较好的适应性.
Combining the RPTSIM (renewal precise time step integration method) with the basic assumptions of constant average acceleration method of the Newmark family, a new precise integration method is presented and applied to structural seismic response analysis. Calculation formulas and stability of the proposed method are analyzed. When the order of dynamic differential equation is reduced, the size of matrices and equations of the proposed method are only half of that of the RPTSIM. Iterative formulas are straight-forward and the seismic response of displacement, velocity and acceleration can be obtained more conveniently. Although the presented method is conditionally stable, the conditions are very easy to be satisfied. Numerical studies indicate that the proposed method is effective and applicable to analyzing earthquake action.