预应力CTRC板加固持载混凝土梁的抗弯性能研究

采用四点弯曲试验研究用预应力碳纤维织物增强混凝土板加固持载RC梁的抗弯性能。针对梁的持载水平完成2个加固工况试验及1个参考工况试验。对各工况试验梁的荷载-跨中挠度曲线、荷载-应变曲线、承载力、延性及破坏模式进行分析。研究结果表明:预应力CTRC板能明显提高持载混凝土梁的正常使用极限状态荷载和极限承载力但加固梁的延性降低。与未加固梁相比,加固梁的正常使用极限状态荷载和极限承载力最大分别提高了64.1%和80.6%。本文提出的一种加固梁极限承载力的计算方法,其极限承载力的计算值与试验值吻合良好。

Flexural behavior of RC beams repaired with prestressed CTRC plates under sustaining loads

In this paper, flexural behavior of reinforced concrete(RC) beams repaired with prestressed carbon textile reinforced concrete(CTRC) plates under sustaining loads was studied by four-point bending test. Two repaired cases and a reference case were completed according to the sustaining load level. The load-middle span deflection curves, load-strain curves, bearing capacity, ductility and failure modes of all test cases were analyzed. Experimental results indicate that the use of prestressed carbon textile reinforced concrete(CTRC) plate can significantly improve the serviceability limit state load and ultimate load of RC beams under sustaining loads. But the ductility of repaired beams decreased. Compared to the unstrengthed beam, the maximum increase rate of the serviceability limit state load and ultimate load of repaired beam reached 64.1% and 80.6% respectively. The calculation method for the ultimate load of repaired beams is presented. A comparison between the calculated and experimental results revealed a satisfactory agreement.