楼梯间外纵墙一字形墙肢的稳定性问题及处理  

STABILITY ANALYSIS AND STRENGTHENING OF RECTANGULAR LONGITUDINAL EXTERIOR WALL IN STAIRCASES

作　　者：蔚博琛 张敬书[1,2] 于晓旭 柳涛[2,4] WEI Bo-chen;ZHANG Jing-shu;YU Xiao-xu;LIU Tao(Key Laboratory of Mechanics on Disaster and Environment in Western China of the Ministry of Education,Lanzhou University,Lanzhou 730000,China;School of Civil Engineering and Mechanics,Lanzhou University,Lanzhou 730000,China;China Northeast Architectural Design & Research Institute Co.,Ltd,Shenyang 110000,China;Shandong Provincial Architectural Design & Research Institute Co.,Ltd,Jinan 250000,China)

机构地区：[1]兰州大学西部灾害与环境力学教育部重点实验室,兰州730000 [2]兰州大学土木工程与力学学院,兰州730000 [3]中国建筑东北设计研究院有限公司,沈阳110000 [4]山东省建筑设计研究院有限公司,济南250000

出　　处：《工程力学》2019年第8期133-140,共8页Engineering Mechanics

基　　金：国家自然科学基金项目(51678283)

摘　　要：高层建筑中,部分剪力墙楼梯间外纵墙两侧仅通过连梁与其它墙肢相连,由于剪力墙先于楼梯施工,该墙肢为无支高度较高的一字形墙肢,存在平面外失稳的可能,从而使结构设计偏于不安全。该文首先根据能量法基本原理,考虑施工完成前和完成后两种工况,建立了一字形墙肢考虑自重时平面外失稳的计算方法,并采用有限元数值模拟验证了该方法的正确性。然后以某高层剪力墙结构为例进行验算,指出楼梯间外纵墙一字形墙肢存在失稳的可能。最后给出了四种处理方法:添加翼缘或风井、梯板分布筋锚入一字形墙肢中整浇、用填充墙替代一字形墙肢及计算时不考虑一字形墙肢承担地震作用,并对上述方法进行了分析。该文认为,取消一字形墙肢,沿层高处布置梁,梁上设置轻质填充墙,则可避免楼梯间一字形墙肢的稳定性问题。该做法施工方便,建议采用。但在地震区,需提高楼梯间轻质填充墙的抗倒塌能力,保证生命通道的畅通。High-rise buildings are often associated with stability problems of longitudinal exterior walls in staircases.The longitudinal exterior walls,of no support,are generally connected to other parts of the building by coupling beams.In traditional structure design,the stability of the walls is often overestimated when the walls subject to transverse bending.This study investigated the stability issue of out-plane bending of longitudinal stair walls under self-weight.Firstly,a theoretical method was proposed to calculate the critical loading based on the energy principles.The theoretical results were in good agreement with the results of finite element simulation.Subsequently,a high-rise shear wall structure was taken into consideration as a case study.The results show that the instability of the rectangular longitudinal exterior wall in staircase might occur.Finally,four measures were suggested to maintain the wall stability:1) adding flanges or air shafts;2) anchoring the distributed reinforcements of stair slabs into the rectangular wall;3) replacing the rectangular wall with the infill wall,and 4) calculating the earthquake action without taking into account the rectangular wall.Based on the analysis results of the four measures,it has been concluded that abolishing the rectangular wall,arranging the beam at the story height,and setting the lightweight infill wall on the beam can avoid the stability issue of the rectangular wall in a staircase.This measure is easy to construct and is recommended.However,in seismic zones,improving the collapse-resistant capacity of lightweight infill walls in staircases is necessary to keep the emergency exit unimpeded.

关 键 词：高层剪力墙 稳定性 能量法 一字形墙肢 有限元模拟 

分 类 号：TU973.2[建筑科学—结构工程] TU398.2