预应力AFRP筋混凝土梁受弯性能的试验研究  

EXPERIMENTAL STUDY ON THE FLEXURAL BEHAVIOR OF CONCRETE BEAMS PRESTRESSED WITH AFRP TENDONS

作　　者：涂永明[1] 张继文[1] 钱洋[2] 陈杰 

机构地区：[1]东南大学混凝土及预应力混凝土结构教育部重点实验室,南京210096 [2]东南大学建筑设计研究院,南京210096 [3]南京市民用建筑设计研究院,南京210002

出　　处：《工业建筑》2009年第4期72-76,共5页Industrial Construction

基　　金：国家自然科学基金重点项目(50238030);国家自然科学基金资助项目(50178018;50808039);江苏省自然科学基金资助项目(BK2008148);教育部博士点基金新教师项目(20070286095)

摘　　要：对一组配置芳伦纤维增强塑料AFRP预应力筋的简支梁进行受弯试验,考察AFRP筋配筋率、张拉控制应力、非预应力钢筋配筋率等因素对构件承载能力的影响,分析了开裂荷载、极限荷载、荷载-挠度关系、裂缝发生发展、平截面假定、AFRP筋和普通钢筋的应变发展状况等。试验结果表明:有粘结预应力AFRP筋混凝土梁的受载全过程可分为三个阶段,即从加载到混凝土开裂,再到非预应力筋屈服,最终达到极限承载力;虽然AFRP筋材没有屈服点,但是其弹性模量较低,因此,试验梁破坏前有明显的变形和预兆;破坏时,AFRP筋应变不一定达到极限,其值可按平截面假定计算;此外,试验表明,适当提高张拉控制力能提高梁的极限承载能力。A group of simple beams prestressed with AFRP tendons or steel strand have been tested. The effect of several factors, such as the reinforcement ratios of AFRP tendon and steel rebar, the prestressing force, etc, on the load-carrying capacity of the beams is investigated. And the cracking load, the ultimate load, the load-deflection relationship, the crack development, the plane-section assumption, and the strain developments of AFRP tendon and steel reinforcement are discussed. The results demonstrate： the whole mechanical process of the concrete beam prestressed with AFRP tendons can be idealized to the trilinear relationship. The first stage is from loading to cracking, the second to yield of the tension steel, and the third to the ultimate load-carrying capacity. Although the AFRP tendon material has no the yielding plateau, the beams prestressed with AFRP tendons show clear deformation signs before collapsing because of the low elastic modulus of the AFRP material. When the beams collapse, the AFRP tendon will not always reach the ultimate strain value and its strain can be calculated with the plane-section assumption. In addition, the ultimate load-carrying capacity of the beams can be improved by increasing the prestressing force.

关 键 词：AFRP筋 受弯性能 平截面假定 极限承载能力 荷载-挠度曲线 

分 类 号：TU378.2[建筑科学—结构工程]