非线性大变形问题一直是钢筋混凝土梁数值分析中的难点,有限元方法中的网格畸变会大大降低其求解精度,而无网格方法由于不受网格的束缚,能很好地处理钢筋混凝土的大变形问题。为准确求解非线性大变形问题,本研究发挥无网格法的优点,利用无网格法建立钢筋混凝土梁数值计算模型,对模型分别施加恒定静荷载和动荷载,以探讨无网格伽辽金算法求解情况下钢筋混凝土梁的应力变形情况及破坏模式。结果表明,动、静加载下,梁最大应力值随着加载的变化而呈现不同的变化趋势,钢筋混凝土梁的应力变形均符合实际规律,无网格法可以用于解决钢筋混凝土梁的大变形求解问题。
The nonlinear large deformation has always been a difficulty in the numerical analysis of reinforced concrete beams, and the mesh distortion will greatly reduce solution accuracy in the finite element method (FEM), while grid points in the meshless method are not constrained by the grids, so this method can well handle the nonlinear large deformation problem in reinforced concrete beams. To solve the problem of nonlinear large deformation accurately, we establish a numerical model of reinforced concrete beam on the basis of the meshless method, and the static and dynamic loads are applied on the model to analyze the stress, deformation and failure mode of the reinforced concrete beam. The results show that either under the static or dynamic loads, the maximum stress varies with the change of load, and the stress and deformation of the reinforced concrete beam are consistent with the actual law, demonstrating the meshless method can be used for the nonlinear large deformation problem.
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