【摘要】 采用有限元分析方法(FEM)对三点弯曲混凝土梁的能量释放率进行了计算,在对混凝土梁进行单元划分时,避免使用奇异性单元来模拟梁的裂尖奇异性。在梁的中线上采用双重节点技术,逐步释放裂尖单元节点的方法来模拟裂纹的扩展。基于虚拟裂纹闭合方法,分别对不同裂纹长度的混凝土梁进行了计算。计算结果表明,用该方法计算出来的能量释放率与理论值有很好的吻合性,证实了该方法的可行性。更多还原

【Abstract】 Calculation of the energy release rate with finite element method (FEM ) is conducted. The concrete beam model is meshed using a method without need of considering the crack-tip singular element. Two columns of nodes, which belong to the right-and left-parts of the beam, respectively, are generated on the central line of the model and released one after another in a proper sequence. Energy release rate is evaluated based on the virtual crack closure technique. Comparison between the calculated values and theoretical values is made, which shows that they are in good agreement.更多还原