体外预应力加固曲线梁试验  

Service Performance of Curve Beam Reinforced by Externally Prestressed Tendon

作　　者：王彤[1,2] 王天阔[1] 顾威[2] 

机构地区：[1]沈阳建筑大学交通工程学院,辽宁沈阳110168 [2]辽宁省交通高等专科学校土木工程系,辽宁沈阳110122

出　　处：《沈阳建筑大学学报（自然科学版）》2016年第6期1017-1025,共9页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家自然科学基金项目(51078242);辽宁省桥梁安全工程技术研究中心项目(201301)

摘　　要：目的研究体外预应力加固对曲线梁构件的裂缝开展、挠度变化、钢筋应力变化等的影响,分析当设置不同的转向块形式时对曲线梁桥力学性能的改变.方法以沈阳市某曲线桥梁作为研究对象,共制作3根缩尺钢筋混凝土曲线箱梁,进行了不同转向形式的加固,通过静载试验分析荷载作用下不同梁的挠度、应力变化及裂缝开展情况,并将理论分析值与试验值进行比较.结果体外预应力可以有效提高曲线梁的承载能力,抑制裂缝的发展和梁的变形;设置多个转向块单转向块的加固梁能更好地改善曲线梁的受力,提高承载能力.体外预应力能有效降低梁的下挠,改善梁的变形.在试验过程中,同一片梁,在相同荷载作用下,加固侧梁的变形明显变小.体外应力能有效地抑制裂缝开展,使裂缝部分闭合.在试验过程中,同一片梁,在相同荷载作用下,加固侧的梁的裂缝明显变小.不同的体外预应力布筋形式对闭合裂缝的效果也有明显差异.结论多转向块的加固形式对于对闭合裂缝,抑制裂缝开展有明显作用.曲线梁采用多转向块加固能改善梁的受力性能,较单转向块加固梁受力更加合理,承载能力更高.The effects of external prestressing reinforced on the crack development, deflection and stress change of steel bar for curved beam was tested, and the mechanical properties of curved girder bridge was analyzed when different steering block are setted up on it. A real curve bridge is as a research subject in Shenyang. Three reduced scale of reinforced concrete curved box girders were made, which were reinforced by different steering forms. The crack development of specimens under the loads,the changes of span deflection and reinforcement stress were investiga-ted in the static load test, and the theoretical analysis and test values compared. The bearing capacity is effectively improved, and the development of the crack and the deformation were re- strained for the curved beams reinforced by externally prestressed. Setting up more steering blocks can improve the bearing capacity of curved beams better than that setting up single steering block. Extemal prestressing can effectively reduce the deflection of the beam,improve the deformation of the beam. Under the same load, the deformation and fractures on reinforcing side of the beam are obviously smaller than another side. The effect of setting up different external prestressing tendons on cracks closing has obvious difference. The curved beam reinforced with more than one steering block can improve the mechanical properties and bearing capacity, and inhibite crack growth of curved beam, which is more reasonable than being reinforced with one steering block.

关 键 词：曲线梁 体外预应力 加固 转向块 

分 类 号：TU311[建筑科学—结构工程] P315.9[天文地球—地震学]