两空间结构风致内压的复特征值分析

摘要

The effects of wind-induced internal pressure on a two-compartment building with opening cannot be neglected.In this paper,the complex eigenvalue analysis of the non-linear equations proposed by Sharma was conducted.Then,the expressions of natural frequency and damping ratio for the internal pressure-building system were obtained.Finally,the changing tendency of natural frequency and damping ratio with the opening areas of wind-ward and partition walls were studied by using a typical numerical example.The results show that the damp of the system is rather small in case of different opening areas of wind-ward and partition walls.With the decrease of the opening area of wind-ward wall,the firstorder damping ratio rapidly increases,but the second-order damping ratio keeps unchanged.Additionally,the two orders damping ratios present a decreasing tendency with the increase of the opening area of partition wall.%对Sharma提出的两空间结构风致内压线性控制方程组进行复特征值分析,获得了“结构-内压”系统自振频率与阻尼比的表达式.通过典型数值算例,计算分析了系统的自振频率、阻尼比随迎风墙和隔墙开洞面积的变化规律.结果表明,在不同的迎风墙与隔墙开洞面积下,“结构-内压”系统的自身阻尼较小.随着迎风墙面开洞面积的减小,第一阶振型阻尼比急剧增大,但第二阶振型阻尼比基本保持不变;随着隔墙开洞面积的增大,前两阶阻尼比均呈递减趋势.