混凝土T形梁预应力损失及预应力钢筋应力增量分析  

Analysis on Prestressing Loss of Concrete T-shape Beam and Stress Increment of Prestressing Reinforced

作　　者：戎贤[1,2] 仉庆文[1,2] 赵玉婷[1,2] 

机构地区：[1]河北工业大学土木工程学院,天津300401 [2]河北省土木工程技术研究中心,天津300401

出　　处：《混凝土与水泥制品》2015年第5期38-41,共4页China Concrete and Cement Products

基　　金：天津市自然科学基金项目(12JCYBJC14100);河北省交通运输厅科技计划项目(Y-2011052);河北省交通运输厅科技计划项目(Y-2012041)

摘　　要：选取某大桥有粘结预应力钢筋混凝土T形梁作为试验梁,在跨中进行集中力分级加载,预应力钢筋应力增量由锚具和预应力钢筋与注浆之间的粘结力共同传递给混凝土,分析了二者承担的比例及该梁的预应力损失。研究发现,在分级加载过程中,应力增量主要是由预应力钢筋与注浆之间的粘结力传递给混凝土,由锚具承担的部分可以忽略不计。并将该梁预应力损失的理论值与实测值进行比较,得出理论值与实测值的比值在1.52左右,说明规范中规定的曲线有粘结预应力筋预应力损失的计算公式偏于保守。Choosing a bonded prestressed reinforced concrete T-shaped beam from some bridge as the test beam, the single force is exerted on the mid span of the beam by gradation loading. The stress increment of prestressed steel is transmitted by the anchor device and the binding power between the prestressed steel and the cement paste.The force sharing ratio of the prestressed steel and the cement paste and prestressing loss of the beam are analyzed.It＇s found that during the loading process, the stress increment is mainly transmitted by the binding power, and the bearing part of anchor device can be ignored. Theoretical value and measured value of the prestressing loss are compared. The results show that the ratio of the theoretical value and measured value is about 1.52, which means the specified computational formula about prestressing loss of the bonded curved presstressed steel is conservative.

关 键 词：粘结力 混凝土T形梁 预应力损失 应力增量 

分 类 号：TU528.79[建筑科学—建筑技术科学]