摘要
对6根预应力碳纤维(CFRP)布加固钢筋混凝土梁进行了预应力损失和弯曲静载试验,确定了后张预应力碳纤维布加固钢筋混凝土梁的剥离-断裂破坏形态,得到了破坏时CFRP布的有效应变.试验结果表明,瞬时预应力损失是总损失的主要部分,而随时间依存的预应力损失仅为初始预应力的2.3%～3.9%.胶体的养护时间对瞬时预应力损失具有一定影响.使用外贴预应力CFRP布加固钢筋混凝土梁后,其正常使用性能得到明显改善,承载力有较大提高.最后,给出了预应力损失及考虑预应力损失的抗弯承载力的计算模型.计算结果表明,计算值与文献中的试验值吻合较好,使用该计算模型可以有效地预测预应力损失和加固梁的抗弯承载力.
Experimental works on six reinforced concrete （RC） beams strengthened with post- tensioned carbon fiber reinforced polymer （CFRP） sheets were conducted to investigate the short and long-term prestress losses and flexural behaviors. The debonding-rupture （DR） failure mode was presented and the effective strain of CFRP sheet was given under DR failure mode. The experimental results show that the instantaneous prestress loss due to anchorage set is the main part of the total prestress loss and the time-dependent prestress loss is only 2.3 % - 3.9 % of the initial prestress of CFRP sheet. The cured period of epoxy resin affects the instantaneous prestress loss. The serviceability of strengthened beams is improved and the capacity is enhanced significantly after using the externally bonded prestressed CFRP sheet. Finally, an analytical model was proposed to calculate the prestress losses and flexural capacity of strengthened beams. The calculation results show that the calculated values agree well with the test results in litera- ture, indicating that this analytical model is effective to predict the prestress losses and flexural capacity of strengthened beams.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2013年第1期195-202,共8页
Journal of Southeast University：Natural Science Edition
基金
国家自然科学基金资助项目(51078079)
关键词
预应力CFRP布
剥离-断裂破坏
预应力损失
抗弯承载力
计算方法
prestressed carbon fiber reinforced polymer （CFRP） sheet
debonding-rupture failure
prestress losses
flexural capacity
calculation method
