体外预应力高强混凝土三跨变截面连续梁试验研究  

The test and study of Three-Span Externally Prestressed Continuous Concrete Beams With Various Sections

作　　者：杨莉[1] 赵人达[2] 张晓勇[2] 

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]中铁大桥勘测设计院,湖北武汉430050

出　　处：《铁道学报》2005年第6期128-133,共6页Journal of the China Railway Society

基　　金：成都市建委专项基金资助项目

摘　　要：简要介绍了四片体外预应力高强混凝土变截面连续梁的设计与制作过程,由静力测试结果可知,在承载能力极限状态下,连续梁裂缝宽度随预应力比率即PPR取值的增大而增大,其数量随PPR取值减小而增多;普通钢筋可以有效地限制裂缝的发生和发展;体外预应力筋的应力增量与中跨中挠度变化近似成线性关系,可用三折线刚度折减的办法,按弹性理论计算试验梁的挠度及预应力筋的应力增量。This paper concisely introduces the design and made course of 4 three-span external pre-stressed continuous concrete beams with different external pre-stressing and various section. The test results show that： on maximum state, the width of crack extends if PPR extends and the number of crack increases if PPR reduces; this kind of structure has good ductility and the conventional reinforcing steel bars are favorable to separating cracks and restricting cracks propagation. The stress increment of external pre-stressing tendons is linear with the increase of deflection and a calculating method of stress increase and deflection is proposed.

关 键 词：体外预应力 连续梁 计算方法 

分 类 号：U445.47[建筑科学—桥梁与隧道工程]