故宫中和殿某中金檩加固分析

Strengthening analysis of a mid inner purlin in Zhonghe Palace in the Forbidden City

为探讨古建筑木结构的有效加固方法,以故宫中和殿某开裂的中金檩为例,采用数值模拟手段,对其加固方案进行了分析。基于该中金檩开裂现状,提出了2种加固方案:辅梁法和附加斜撑法。采用有限元分析程序ANSYS,建立了上述2种加固方案的有限元模型,进行了数值模拟分析,获得了不同加固方案条件下中金檩体系的内力和变形结果。结果表明:辅梁法虽然能改善中金檩的抗弯性能,但中金枋与辅梁相交位置很可能产生受拉破坏,因此该方案不可行;附加斜撑法满足中金檩承重体系的内力和变形要求,因而可满足中金檩加固要求。

To find effective strengthening methods for Chinese ancient wooden buildings, a ruptured mid inner purlin in Zhonghe Palace in the Forbidden City was taken as example to study its strengthening methods by simulation. Based on rupture actuality of the purlin, 2 strengthening methods were proposed： additional beam method and additional oblique supports method. Finite element models of the purlin strengthened by the 2 methods were built by ANSYS program. Simulation analyses were carried out, internal forces as well as deformation status of the strengthened purlin were obtained, strengthening effects of the 2 methods were discussed. Results show that additional beam method can improve bending performance of the purlin, but it may he destroyed on intersectant position between its tiebeam and the additional beam because of tension strength failure ; additional oblique supports method meets the demands of interual forces and deformation of the purlin, thus the method is feasible.