某体育场超长结构的温度应力分析与预应力设计  

Temperature stress analysis and prestress design for a sport stadium with a super long structure

作　　者：迟晓彤 Chi Xiaotong(Zhongsen Architectural&Engineering Designing Consultants Ltd.,Shanghai 200062,China)

机构地区：[1]上海中森建筑与工程设计顾问有限公司,上海200062

出　　处：《山西建筑》2024年第14期65-68,共4页Shanxi Architecture

摘　　要：某体育场采用混凝土框架结构体系,屋面采用钢桁架,底层看台由抗震缝分为四个结构单元,其中东西看台纵轴长度约241 m,为超长混凝土结构。由于混凝土收缩效应和季节温差效应,可能导致楼板在平面内产生较大的拉应力,从而产生裂缝。综合考虑混凝土徐变引起的收缩应力,以及季节温差引起的温度应力,对楼板应力进行了计算分析。分析结果表明:在混凝土自身收缩和外部温差作用下,楼板平台段和阶梯段越靠近中间区域拉应力越大,最大拉应力约3 MPa。根据应力分析结果,在平台段和阶梯段分别施加间距为600 mm和830 mm的无粘结预应力筋。经验算,预应力筋能够完全抵抗混凝土自身收缩和外部温差作用下楼板平面内的拉应力,避免结构在正常使用状态下产生有害裂缝,为超长混凝土结构设计提供了有效的设计建议。This paper is focused on a sports stadium which adopts a super-long concrete frame structure system,with a steel truss roof.The bottom grandstand is divided into four structural units by seismic joints.The longitudinal axis length of the east and west grandstands is about 241 m.Due to the effects of concrete shrinkage and seasonal temperature differences,the floor slab will generate significant thermal stress in the plane,resulting in cracks.This article analyzes the stress of the floor slab,considering the shrinkage stress caused by creep in concrete and the temperature stress caused by seasonal temperature difference.The results indicate that under the action of concrete self-shrinkage and external temperature difference,the closer the floor platform section and step section are to the middle area,the greater the tensile stress,with a maximum tensile stress of about 3 MPa.According to the stress analysis results,unbonded prestressed steel bars with spacing of 600 mm and 830 mm were applied to the platform section and step section,respectively.The results demonstrated that prestressed steel bars can fully resist the tensile stress in the floor slab plane under the action of concrete shrinkage and external temperature difference,which avoids cracks in the structure under normal use.The results can provide reference for the design of super-long concrete structures.

关 键 词：体育场 超长混凝土结构 温度应力 收缩 预应力 

分 类 号：TU245.1[建筑科学—建筑设计及理论]