钢筋混凝土箱拱面内受力全过程试验研究

Experimental research on whole process behaviors of reinforced concrete box arch under in-plane loads

进行了钢筋混凝土箱拱面内受力全过程试验.应用通用程序ANSYS建立了钢筋混凝土箱拱的非线性有限元模型,对模型拱面内受力全过程的非线性受力性能进行了分析.对结构破坏模式进行了探讨,并采用极限分析简化算法对极限承载力进行了计算.研究表明,在面内两点非对称荷载作用下,钢筋混凝土箱拱的破坏模式与实肋板拱相似,均属于以材料非线性为主的二类稳定问题.进行钢筋混凝土箱拱的极限承载力计算时,不可忽略几何非线性的影响,应用有限元法分析时应考虑双重非线性的影响.钢筋混凝土箱拱的结构破坏模式满足刚塑性假定,其极限承载力也可用极限分析法进行简化计算,其结果偏于安全.

Experiment of a reinforced concrete box arch under two loadings asymmetrically in - plane was carried out. ANSYS program was employed to build the finite element model. The nonlinear behavior and its influence on ultimate load - carrying capacity were analyzed. The failure mode was discussed, and the ultimate load -carrying capacity was calculated by the ultimate analysis method. It is indicated that under asymmetrical loading, the failure mode of the tested arch is similar with that of solid rib arch, the material nonlinearity is dominated in its peak - point instability. The effect of geometric nonlinearity can＇ t be neglected in calculation of the ultimate load - carrying capacity by FE method. The ultimate analysis method can be employed with a conservative result in the calculation of load - carrying capacity.