大跨预应力张弦桁架施工全过程的有限元分析  

FINITE ELEMENT ANALYSIS OF LONG-SPAN PRESTRESSED TRUSS STRINGS STRUCTURE CONSTRUCTION

作　　者：宋昭 SONG Zhao(China IPPR International Engineering Co.,Ltd.,Beijing 100089,China)

机构地区：[1]中国中元国际工程有限公司,北京100089

出　　处：《低温建筑技术》2020年第5期91-95,共5页Low Temperature Architecture Technology

摘　　要：某干煤棚主体结构由21榀跨度为126m的预应力张弦桁架组成,受施工场地限制,张弦桁架无法进行原位安装及张拉,为选择合理的施工方案并明确其可行性,分析了分段吊装加高空合拢的吊装方案,并采用有限元方法对张弦桁架的张拉及累积滑移进行了研究。结果显示主桁架分段吊装过程中应力和位移较小;张弦桁架中拉索的张拉仅对相邻拉索的索力影响较大;累积滑移时需要将张弦桁架的柱脚不同步位移控制在一定的范围内;滑移过程中结构最大组合应力呈上升趋势,但均小于材料强度的设计值。分析表明分段吊装累积滑移的施工方案合理可行,可为同类工程提供参考。The main structure of a coal shed is composed of 21 prestressed string trusses with a span of 126m.Due to the constraints of the construction site,the string truss cannot be installed and tensioned in situ.Fora reasonable construction plan and its feasibilityclarification,the lifting scheme of subsection hoisting and high-altitude closing was analyzed,in addition,the tension and cumulative slip of the string chord using finite element method was studied.The results show that the stress and displacement of the main truss during subsection hoisting are small,and the tension of the cable in the string truss only affects the cable force of the adjacent cable.Furthermore,the asynchronous displacement of the column foot of the string truss needs to be controlled within a certain range during cumulative slip.In the sliding process,the maximum combined stress of the structure increases,but it is less than the design value of the material strength.The analysis shows that construction scheme of section lifting and cumulative slip is reasonable and feasible,which maybe used as reference for other similar projects.

关 键 词：施工全过程有限元分析 大跨张弦桁架 累积滑移施工 张拉分析 

分 类 号：TU378[建筑科学—结构工程]