装配式钢框架-减震围护墙的构造与机理研究

Research of construction and mechanism on prefabricated steel frame-damped enclosure wall

针对装配式钢框架结构存在的带门窗洞口围护墙体系易遭受地震破坏以及围护墙的附加刚度和约束效应对结构抗震不利等问题,提出一种开设门窗洞口的减震墙体——减震围护墙。为验证装配式钢框架-减震围护墙的工作机制,采用ABAQUS软件对减震围护墙(开洞)-框架单元、普通围护墙(开洞)-框架单元和减震墙板(未开洞)-框架单元进行建模分析,对比研究不同墙体对框架附加刚度、墙板应力和洞口变形的影响。结果表明:与普通围护墙相比,减震围护墙为框架提供的附加抗侧刚度和水平承载力大大减小,解决了普通围护墙过强的约束作用和附加刚度效应对结构抗震不利问题;在大位移加载工况下,减震围护墙一方面可避免墙体破坏,另一方面可减小或避免门、窗洞口变形,起到保护门、窗部件作用,从而保证地震时逃生和震后开展应急救援工作;减震围护墙对框架的附加作用主要由减震层提供,门窗开洞对框架受力性能影响较小;设置减震围护墙可避免门洞或窗洞洞口角部发生局部破坏;装配式钢框架-减震围护墙的"墙-梁"型连接构造合理可靠,门窗开洞对连接件受力影响较小。

A novel damped enclosure wall(DEW),considering the setting of door opening or(and)window opening,was proposed to solve seismic problems in prefabricated steel frame structure including earthquake-prone enclosure wall system(i.e.partition wall with door opening or(and)window opening),and adverse seismic influences caused by added stiffness and constraints from enclosure wall.In order to verify the working mechanism of prefabricated steel frame-damped enclosure wall(PSF-DEW),the finite element models of one-story single-bay prefabricated steel frame including damped enclosure wall with opening,canventional enclosure wall with opening and solid damped wall without opening were simulated by software ABAQUS,as well as comparative study on the added stiffness,stress of wall and deformation of opening that different walls exert was carried out.The results of research indicate that,compared to the conventional enclosure wall,damped enclosure wall can provide less added horizontal bearing capacity and lateral stiffness of the frame,and therefore,the adverse effects in seismic resistance of structure attributed to the excessive constraints and added stiffness from conventional enclosure wall can be avoided.The DEW can avoid damages of wall and also highly alleviate the deformation of door or window openings under large loading displacement,so that people can escape during the earthquake and carry out post-earthquake emergency rescue work.The added effect from DEW to frame is mainly provided by damping layer,and the door opening or window opening on DEW has little impact on mechanical performance of the frame.The DEW with door opening or window opening doesn’t have the local damage to the corner of opening.The wall-beam connection of PSF-DEW is available,the door opening or window opening on DEW has a little influence on the stress of fastenings.