中文摘要：

研究起重机箱梁剪应力和纯弯曲作用箱梁局部腹板的屈曲失稳力学问题。为了保证设备安全,针对复合受载局部矩形板屈曲失稳的数值解与解析解编程繁琐、及工程经验公式解往往不够精确的问题,首先给出矩形板屈曲失稳的工程经验公式解;并系统研究了有限元屈曲仿真分析的求解方法;同时给出了能量变分法解析求解的方程式。通过对比有限元数值解与解析解,验证了有限元数值解的精确性。最后,以某起重机箱梁腹板局部屈曲失稳校验分析为例,通过对比有限元数值解与经验公式解,验证表明经验公式解较有限元数值解能保证安全性。

英文摘要：

The box girder＇s local buckling stability is inwestigated for the web plate under the shear force and pure bending loading case. For the rectangular plate＇s critical buckling load, the numerical solution and analytic solution can＇t be got easily, and the empirical formula is usually not accurate. Firstly, the traditional method in the engineer- ing is given concretely, and the FEM method is analyzed systematieally. Meanwhile, the energy variation method is chosen to get the equations for the analytic solution. By the comparison between the FEM solution and analytic solu- tion, it is shown that the critical buckling load can be obtained accurately by the FEM solution. Finally, a practical crane＇s box girder is chosen as the example to check the web plate＇s local stability, the empirical formula is compared with the FEM solution, it is shown that the empirical formula is less accurate than the FEM solution.