TY - EJOU AU - Ji, Yi AU - Xing, Yufeng TI - An Improved Higher-Order Time Integration Algorithm for Structural Dynamics T2 - Computer Modeling in Engineering \& Sciences PY - 2021 VL - 126 IS - 2 SN - 1526-1506 AB - Based on the weighted residual method, a single-step time integration algorithm with higher-order accuracy and unconditional stability has been proposed, which is superior to the second-order accurate algorithms in tracking long-term dynamics. For improving such a higher-order accurate algorithm, this paper proposes a two sub-step higher-order algorithm with unconditional stability and controllable dissipation. In the proposed algorithm, a time step interval [tk, tk + h] where h stands for the size of a time step is divided into two sub-steps [tk, tk + γh] and [tk + γh, tk + h]. A non-dissipative fourth-order algorithm is used in the rst sub-step to ensure low-frequency accuracy and a dissipative third-order algorithm is employed in the second sub-step to lter out the contribution of high-frequency modes. Besides, two approaches are used to design the algorithm parameter γ. The rst approach determines γ by maximizing low-frequency accuracy and the other determines γ for quickly damping out highfrequency modes. The present algorithm uses ρ∞ to exactly control the degree of numerical dissipation, and it is third-order accurate when 0 ≤ ρ < 1 and fourth-order accurate when ρ = 1. Furthermore, the proposed algorithm is self-starting and easy to implement. Some illustrative linear and nonlinear examples are solved to check the performances of the proposed two sub-step higher-order algorithm. KW - Time integration algorithm; two-sub-step; higher-order accuracy; controllable dissipation; unconditional stability DO - 10.32604/cmes.2021.014244