冻融循环后预应力混凝土梁受弯性能研究*
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（1 江苏大学土木工程与力学学院， 镇江 212013; 2 扬州大学建筑科学与工程学院， 扬州 225127）
［摘要］为研究冻融循环次数对预应力混凝土梁受弯性能的影响，制作了普通混凝土梁和预应力度分别为0.35，0.52和0.62的预应力混凝土梁各4根，将构件经历一定次数的冻融循环后进行静力受弯性能试验。研究表明，预应力度和冻融循环次数对预应力混凝土梁的承载力影响比较明显，随冻融循环次数的增加，预应力混凝土梁的受弯承载力明显下降。中、低预应力度混凝土梁的受弯承载力随冻融循环次数增加而下降的速率较高预应力度混凝土梁的缓慢。冻融循环后预应力混凝土梁的开裂弯矩可按规范相关公式计算，极限弯矩也可按规范公式计算，但需考虑综合影响系数。［关键词］预应力混凝土梁; 预应力度; 冻融循环; 受弯性能中图分类号：TU375.1 文献标识码：A 文章编号：1002-848X(2015)24-0101-05
Study on the mechanical behaviors of prestressed concrete beams after freeze-thaw cyclesLi Congqi1, 2, Ge Wenjie2, Cao Dafu2(1 College of Civil Engineering and Mechanics, Jiangsu University, Zhenjiang 212013, China; 2 College of Civil Science and Engineering, Yangzhou University, Yangzhou 225127, China)Abstract: In order to study the flexural behavior of prestressing concrete beams after freeze-thaw cycles, four normal concrete beams and four prestressed concrete beams with three different partial prestressing ratios (PPR) 0.35, 0.52 and 0.62 were made and theirs static flexural experiments were carried out after certain freeze-thaw cycles. The results show that PPR and freeze-thaw cycles are the two main influence factor to the flexural behavior of prestressing concrete beams. Ultimate moment decreases significantly with the increasing of freeze-thaw cycles. Ultimate moments of prestressing concrete beams with moderate and low PPR decrease slower than prestressing concrete beams with high PPR. Cracking moment of prestressed concrete beams after the freeze-thaw cycle could calculate by current design code of concrete structure. Ultimate moment could also calculate by current design code, but comprehensive influence coefficient should be taken into consideration.Keywords: prestressed concrete beam; partial prestressing ratio (PPR); freeze-thaw cycle; flexural behavior
*国家自然科学基金资助项目(51278445, 51278230, 50978224)， 江苏省普通高校研究生科研创新计划 (CXZZ12-0655)。作者简介：李琮琦，硕士，讲师， Email: licq@yzu.edu.cn。
