拱效应下纵向约束刚度对GFRP筋混凝土桥梁面板力学性能的影响  

INFLUENCE FROM STIFFNESS OF LONGITUDINAL RESTRAINT ON STRUCTURAL BEHAVIOURS OF CONCRETE BRIDGE DECK SLABS REINFORCED WITH GFRP BARS WITH ARCHING ACTION

作　　者：李春红[1] 郑愚[1] 魏德敏[2] 

机构地区：[1]东莞理工学院建筑工程系,东莞523808 [2]华南理工大学亚热带建筑科学国家重点实验室,广州510641

出　　处：《玻璃钢／复合材料》2013年第3期47-52,共6页Fiber Reinforced Plastics/Composites

基　　金：国家自然科学基金资助项目(50908055);东莞市科技计划项目(2011108102027);广东省交通厅科技计划项目(2011-02-040);东莞理工学院自然科学青年基金资助项目(ZN100028)

摘　　要：混凝土桥梁面板受到外围构件的约束时会在内部形成拱效应,在拱脚处产生沿板跨纵向的约束力。为了研究纵向约束刚度对板带力学性能的影响,对6块端部受到转动约束及纵向约束的GFRP筋混凝土试件进行了破坏性实验。从实验中发现:随着纵向约束刚度的增加,约束力逐渐增强,试件受压区范围随之增大,筋材应变减小,跨中挠度及裂缝的发展减缓,板带的正常使用性能及承载力极限值均得到提高。结合前期研究把纵向约束刚度对受压区高度的作用进行量化后,可得到约束力的计算公式,其预测值与实验测得的约束力较为接近。纵向约束力的计算值及实验结果均表明,当纵向约束刚度与板带纵向受压刚度的比值为0.25～2.00时,纵向约束将明显提高板带的力学性能。When concrete bridge deck slabs were restrained by components aside, arching action existed and restraint force acted at arching feet in longitudinal direction of slabs. In order to investigate the influence from vari- ous stiffness of restraint on slabs＇ structural behaviours, six slabs with rotational restraint and longitudinal restraint at both ends were loaded until failed. It showed that as stiffness of restraint rose, restraint force increased, which en- hanced the compressive area and reduced strains of GFRP bars. As a result, development of deflection at central span and cracks was slowed down, and serviceability and ultimate bearing capacity of slabs were both improved. Base on the former research, influence from longitudinal restraint on height of compressive area was quantified and restraint force was deduced. The estimated restraint forces were close to test results. And the conclusion was drawn that when proportion of restraint stiffness to compressive stiffness of slab in longitudinal direction was 0.25 to 2.00, longitudinal restraint would obviously improve structural behaviours of slab.

关 键 词：拱效应 GFRP筋 混凝土桥梁面板 约束刚度 

分 类 号：TB332[一般工业技术—材料科学与工程] TU375.2[建筑科学—结构工程]