基于竖向地震作用下大跨度钢桁架杆件受力分析  

Force Analysis of Large-span Steel Truss Members Based on the Action of Vertical Earthquake

作　　者：焦晋峰[1] 徐弘宇 

机构地区：[1]太原理工大学建筑与土木工程学院,山西太原030024

出　　处：《工程抗震与加固改造》2016年第4期35-41,共7页Earthquake Resistant Engineering and Retrofitting

基　　金：山西省青年科技研究基金资助项目(2012021019-2);太原理工大学校团队基金项目(2014TD043);山西省自然科学基金资助项目(2015011062)

摘　　要：为揭示大跨度钢桁架在竖向地震作用下的杆件内力分布规律,本文基于不同抗震设防烈度及其相应多遇和罕遇竖向地震作用,采用ANSYS模拟5种不同跨度钢桁架的竖向地震响应,并得出"不同竖向地震作用同一跨度条件下"和"不同跨度条件同一竖向地震作用下"钢桁架杆件内力变化规律。分析结果表明:钢桁架杆件动内力系数与设防烈度和跨度成正相关;桁架不同位置处杆件动内力系数变化存在差异,弦杆由跨中向两端逐渐减小,腹杆在0.35L(跨度)和0.6 L(跨度)处存在内力突变。本文分析结果可为今后类似结构设计提供参考。In order to reveal the internal force distribution pattern of large-span steel truss members under the action of vertical earthquake,based on different seismic fortification intensities and their corresponding frequent and rare vertical seismic actions,the vertical seismic responses of 5 steel trusses with different spans are simulates using ANSYS,and the variation pattern of steel truss member internal forces under different vertical seismic action for identical span and identical vertical seismic action for different spans are derived. The analysis results show that： the dynamic internal force factor of steel truss members is positively correlated to the fortification intensity and the span; the factor variation depends on the member location in the truss,because it diminishes from the mid-span toward either end in the case of a chord and an abrupt internal force change exists at 0. 35L（ span） and 0. 65L（ span） each in the case of a web member. This analysis conclusion may serve as reference in future similar structural design.

关 键 词：大跨度钢桁架 ANSYS 反应谱法 竖向地震作用 动内力系数 

分 类 号：TU391[建筑科学—结构工程] TU352.11