地震行波激励下单层对称框架结构扭转响应的时域解析解  

Time-domain analytical solutions for torsional response of single-story symmetric frame structure under earthquake wave passage excitation

作　　者：李文博 刘铁林[1] 王宇[1] LI Wenbo;LIU Tielin;WANG Yu(School of Civil Engineering,Shenyang Jianzhu University,Shenyang 110168,China)

机构地区：[1]沈阳建筑大学土木工程学院,辽宁沈阳110168

出　　处：《地震工程与工程振动》2024年第3期136-145,共10页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(11672190)。

摘　　要：针对单层对称框架结构,利用地震行波激励研究地震波中频率成分对框架结构扭转响应的影响。给出了单层对称框架结构在地震行波激励下的动力平衡方程,利用相对运动法对方程进行求解,给出了地震行波激励下扭转响应级数形式的时域解析解。计算了框架结构分别在低频成分丰富和低频成分不丰富地震波行波激励下的峰值柱剪力,进而分析了地震波中低频成分对框架结构行波效应的影响。研究表明:地震行波激励下柱剪力解析解不但与固有频率和激励频率有关,还与时间延迟以及结构基频和激励频率比值的平方有关。地震波加速度幅值谱中存在小于结构基频的主要频率时,框架结构易于产生行波效应,幅值谱中主要频率均大于结构基频时,不存在行波效应。框架结构地震行波效应除取决于时间延迟外,还取决于地震波中的低频成分。在低频成分和时间延迟的共同作用下,框架结构将产生地震行波效应。低频成分越丰富的地震波,行波效应越显著。The influence of frequency content in earthquake wave on the torsional response of the single-story symmetric frame structure is studied in this paper.The dynamic equilibrium equation for the single-story symmetric frame structure subjected to earthquake wave passage excitation is given,and the relative motion method is adopted to solve the equation.The time-domain analytical solutions in series form to earthquake wave passage excitation are given for torsional responses.The peak column shears of the frame to wave passage excitation are respectively calculated for earthquake waves with sufficient and insufficient frequency content,and the influence of the frequency content on wave passage effect is analyzed.Studies show that the analytical solutions of column shears to wave passage excitation are not only related to the natural frequency and excitation frequency,but also related to the time delay and the square of the ratio of structural fundamental frequency to excitation frequency.The earthquake wave passage effect of frame structure is prone to occur for those earthquake waves whose main frequencies of earthquake acceleration amplitude spectra are lower than the structural fundamental frequency.There is not earthquake wave passage effect for those earthquake waves whose main frequencies are higher than the structural fundamental frequency.The earthquake wave passage effect of frame structure depends not only on the time delay,but also on the low-frequency content.The joint action of low-frequency content and time delay can produce the earthquake wave passage effect.The richer the low-frequency content,the more obvious wave passage effect.

关 键 词：框架结构 地震行波激励 扭转响应 解析解 低频成分 

分 类 号：TU311.3[建筑科学—结构工程]