混凝土结构疲劳损伤全过程模拟的加速算法

Acceleration Algorithm for Whole Fatigue Damage Process Simulation of Concrete

摘要:

基于混凝土随机疲劳损伤本构模型改进了循环跳跃加速算法。将外推变量从损伤变量修改为累积耗能变量，研究了跳跃阈值和外推方式对加速算法计算结果的影响。当选取合适的跳跃阈值时，可以利用较少的逐步计算结果获得更为精确的外推变量信息，使得混凝土疲劳损伤全过程模拟具有更高的精度和更小的计算成本。最后，采用改进加速算法对受压素混凝土梁进行疲劳损伤全过程模拟。结果表明，改进加速算法可以准确高效地模拟混凝土结构的疲劳破坏全过程。

Abstract:

The cycle jump acceleration algorithm is improved based on the stochastic fatigue damage constitutive model in this paper. The extrapolation variable is changed from the damage variable to the energy dissipation variable. Then， the effects of the jump threshold and extrapolation mode on the calculation results of the acceleration algorithm are analyzed. When choosing appropriate jump thresholds， the improved acceleration algorithm can provide more accurate extrapolation variable information with less cycle-by-cycle calculation. As a result， the whole fatigue damage process simulation of concrete is more accurate and requires less computation. By employing the improved acceleration algorithm， the fatigue damage process of a plain concrete beam under compression is simulated. It is shown that the improved acceleration algorithm can simulate the whole fatigue failure process of concrete structures properly and effectively.