中文摘要：

基于线单性断裂力学（LEFM），采用比例边界有限单元法（SBFEM）模拟了混凝土梁混合裂缝扩展。通过与非线性有限单元法（NFM）模拟结果的对比，说明了SBFEM能预测裂缝扩展轨迹，并能准确有效计算荷载位移曲线及其作用点的挠度曲线。

英文摘要：

Based on linear elastic fracture mechanics and the scaled boundary finite element method （SBFEM）, numerical simulation was performed for a mixed-mode crack propagation model. From comparing the results with which obtained by the nonlinear finite element method （NFM）, SBFEM can predict crack trajectories and compute lod-displacement relations as well as load-deflection at loading point accurately and efficiently.