摘要
为了系统研究从零负载状态到满负载状态各个阶段CFRP片材加固梁滞后应变的计算方法,在充分考虑加固梁不同负载状态及受压区混凝土非线性本构关系的基础上,分别建立了不同负载贴片加固梁考虑混凝土抗拉作用时的滞后应变计算公式及不考虑混凝土抗拉作用时的简化计算公式.试验数据和对比分析结果表明:"考虑混凝土抗拉作用"公式的计算结果与试验数据吻合良好,计算误差<8%,明显优于现有文献的计算方法;"不考虑受拉区混凝土抗拉作用"公式的计算结果在混凝土开裂前和试验值相差较大,但对已裂加固梁的计算误差与"考虑混凝土抗拉作用"公式的计算误差接近.为简化计算,对未裂和已裂混凝土梁贴片加固时的滞后应变可分别采用"换算截面"公式和"不考虑混凝土抗拉作用"公式进行计算,两种简化方法的误差均不会超过10%.
To study the method to calculate the lagged strain of carbon fiber - reinforced polymer （CFRP） laminates in CFRP-strengthened reinforced concrete （RC） beams, considering all preloaded states of the beams and the nonlinear stress-strain relationship of compressed concrete, expressions for calculating the lagged strain with or without the consideration of tensile resistance of concrete were derived. Comparison of calculation results with experimental results indicates that the calculation errors of the method considering tensile resistance of concrete are less than 8%, and the calculation errors of the method ignoring tensile resistance of concrete are approximately equivalent to the former in the case of strengthening after cracking, but they are large in the case of strengthening before cracking. To simplify the calculation, the lagged strain can be calculated respectively by the method of conversion - section before cracking or the method ignoring tensile resistance of concrete after cracking. Then the obtained calculation errors are both less than 10%.
出处
《哈尔滨工业大学学报》
EI
CAS
CSCD
北大核心
2009年第8期123-127,共5页
Journal of Harbin Institute of Technology
基金
国家自然科学基金资助项目(50778176)
铁道部科技研究开发计划资助项目(2002G043)
湖南省自然科学基金重点资助项目(09JJ3098)
关键词
钢筋混凝土梁
加固
CFRP片材
滞后应变
负载状态
reinforced concrete beam
strengthening
carbon fiber-reinforced polymer laminate
laggedstrain
preload state
