青城山上清宫门楼古建筑震害机理分析与研究

为了研究门楼古建筑的震后加固改造技术,针对青城山上清宫门楼木石混合结构,进行了实地调查分析.采用混尺度有限元方法,考虑边界非线性影响,建立了门楼独立模型以及考虑台基、牌坊协同作用的数值模型.进行了模态分析,门楼独立模型主周期与规范经验公式相比基本一致,验证了数值模型的合理性.采用瞬态分析方法,对门楼结构变形、基底剪力及构件内力进行了分析.据此,初步提出了拉锚杆原位加固台基石牌坊、爪钉锚固门楼榫卯节点的加固方式.研究表明,门楼动力参与质量相对集中,一旦激振,容易产生较大地震响应;台基的作用导致门楼鞭梢效应明显,但门楼质量较小,地震内力增幅远不如位移明显,木结构较强的变形适应能力有效提高了其抗倒塌能力;古建筑加固需进一步考虑其榫卯节点力学特性的保护与延续.

Seismic Analysis and Research of Gate Tower of Shangqing Temple on Qingcheng Mountain

In order to research retrofitting measures of ancient building with gate tower, an investigation was carried out to Shangqing Temple, a stone-wood structure on the Qingcheng Mountain. Taking into account the nonlinear boundary, the mixed-scale finite element method was adopted to respectively set up the single gate tower numerical model and another considering the cooperation of base and memorial archway. Compared with the national code, the behavior of single gate tower numerical model was analyzed to prove the validity of the numerical model. The deformation, seismic base shear and internal force of its members were investigated by the transient dynamic analysis. The measures of reinforcing the base and stone memorial archway with bolts and anchoring the mortise-tenon joint of tower gate with claw nail were proposed. The results indicated that because the dynamical participated mass of gate tower is centralized, large seismic response will happen when the gate tower was excited. The action of base results in the marked whiplash effect, but the mass of tower gate is small and the amplitude of seismic internal force is much less than the one of displacement. The gate tower has a good ductility to improve its collapse resistant capacity, and retrofitting measures of ancient building should take into account the protection and inheritance of the mechanical behavior of mortise-tenon joint.