(土木工程安全与耐久教育部重点实验室，清华大学土木工程系，北京 100084)

［摘要］点支式玻璃幕墙单层索网的地震反应由于受几何非线性和主体结构的影响，其抗震计算更加复杂。目前抗震规范采用简单的等效静力法计算，地震影响系数亦取线性体系地震影响系数的最大值，未能考虑几何非线性体系结构动力反应的特点，同时也未考虑主体结构的影响，与实际情况严重不符。对点支式玻璃幕墙单层索网地震反应的模态参与特性研究表明，其地震反应以第1阶模态为主，且考虑其质量刚度的均匀分布特性，参考抗震规范中的底部剪力法提出了改进等效静力法，并通过对一组典型索网模型的计算分析验证了此方法的合理性。提出相应的地震影响系数可由线性周期和几何非线性因子控制的单自由度体系求得。大量的分析计算结果表明，主体结构动力影响系数反映主体结构二次输入的影响，其值可通过二者的基本频率比值求得。

［关键词］点支式玻璃幕墙；单层索网；抗震计算；几何非线性；主体结构；实用方法

Seismic analysis method for point-supported glass curtain wall with single-layer cable net

Shi Yongjiu， Li Yong， Wang Yuanqing

(Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry,

Department of Civil Engineering, Tsinghua University, Beijing 100084, China)

Abstract:Due to the influence of geometric nonlinearity of cable net and the second input from the primary structures, seismic analysis for point-supported glass curtain wall with single-layer cable net is more complex. While the current design codes rarely take these effects into account with simple equivalent static method, in which the seismic coefficient is taken as the peak value of linear structures. And it is also unrealistic by ignoring the influence of primary structure. Based on the mode participation properties of cable net under earthquake,it suggests that the first mode is predominant. Combined with the characteristic of even distribution of mass and stiffness of cable net, modified equivalent static method was proposed with validity after comparison with other methods. As for the nonlinear seismic influence coefficient, it can be obtained from the equivalent single-degree-of-freedom with the same linear period and geometric nonlinearity factor. The influence of primary structure can be taken into account with its dynamic influence factor, which varies from the ratio of basic frequency between primary structure and cable net.

Keywords:point-supporting glass curtain wall; single-layer cable net; seismic analysis; geometric nonlinearity；primary structure