免拆模混凝土梁受弯性能试验  

Experiment on Bending Performance of Concrete Beam Without Demoulding

作　　者：吴方伯[1] 左瑞 文俊 刘彪[1] 周绪红[1,2] WU Fang-bo;ZUO Rui;WEN Jun;LIU Biao;ZHOU Xu-hong(College of Civil Engineering, Hunan University, Changsha 410082, Hunan, China;School of Civil Engineering,Chongqing University, Chongqing 400045, China)

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]重庆大学土木工程学院,重庆400045

出　　处：《建筑科学与工程学报》2018年第2期8-15,共8页Journal of Architecture and Civil Engineering

基　　金：国家自然科学基金项目(51278179)

摘　　要：为研究免拆模混凝土梁的受弯性能,设计制作1根免拆模混凝土梁和1根现浇对比梁,对2个试件进行单向静力加载,得到了各试件的破坏形态、荷载特征值、荷载-混凝土应变曲线、荷载-钢筋应变曲线、荷载-跨中位移曲线,并将其进行对比分析。结果表明:在试件屈服前,免拆模混凝土梁与现浇梁的裂缝发展有较大区别,但最终破坏时2个试件的整体破坏特征基本相似;免拆模混凝土梁的预制U形混凝土模块与内部后浇混凝土结合较好,整个加载过程未出现U形模块脱落或撕裂现象;免拆模混凝土梁的开裂荷载相比现浇梁试件要小8%,但2个试件的极限荷载基本相同,实际工程中可采用现行《混凝土结构设计规范》对免拆模混凝土梁的开裂荷载、极限荷载进行计算,结果偏安全。In order to study the bending performance of concrete beam without demoulding,a concrete beam without demoulding and a cast-in-place contrast beam were designed.Two specimens were subjected to unidirectional static loading,and the failure modes,load characteristic values,load-strain curves of concrete,load-strain curves of reinforcement and loaddisplacement curves of midspan were obtained and compared.The results show that the crack development of concrete beam without demoulding and cast-in-place beam is quite different in the pre-yield phase of component,but the overall damage characteristics of the two specimens are basically similar in the end of the failure.The U-shaped concrete formwork of concrete beams without demoulding works well with internal post pouring concrete,and through the entire loading process,the U-shaped concrete formwork doesn＇t fall off and tear.The cracking load of concrete beam without demoulding is about 8% lower than that of the cast-in-place beam,but the ultimate load of the two specimens are roughly the same.In practical engineering project,the current Code for Design of Concrete Structures can be used to calculate the cracking load and the ultimate load of concrete beam without demoulding,and the result is safe.

关 键 词：U形混凝土模块 免拆模混凝土梁 单向静力试验 受力性能 荷载特征值 

分 类 号：TU375.1[建筑科学—结构工程]