钢丝网复合砂浆加固RC梁二次受力受弯试验研究

本文对用钢丝网复合砂浆薄层加固的二次受力钢筋混凝土梁进行了正截面受弯试验研究。通过对加固形式为U形三面加固的5根钢筋混凝土加固梁和1根未加固的对比梁的二次受力正截面受弯试验,研究了这种加固技术对二次受力钢筋混凝土梁受弯承载力的影响和作用。试验中测量了构件加固后的开裂荷载、极限荷载、钢筋应变和钢丝网应变,对比了加固与未加固构件的裂缝开展情况、跨中挠度以及极限荷载,并研究了用钢丝网复合砂浆薄层加固的梁在二次受力情况下可能产生的破坏形式等。试验结果表明,钢丝网复合砂浆薄层可以明显地提高二次受力钢筋混凝土梁的受弯承载力,提高抗裂性能,增强构件的刚度。在平截面假定的基础上求出试件的极限承载力,与试验结果吻合较好。

Experimental study on flexural behavior of reinforced concrete beams strengthened with ferrocement under secondary load

In this paper, the bending responses of RC beams strengthened with ferrocement considering secondary load were experimentally investigated. The test included five RC beams strengthened with ferrocement and one unstrengthened specimen for comparison. The strengthening results of reinforced with three sides(Ushaped ferrocement on the tension surface and two profile surfaces)have been analyzed. Cracking load, ultimate load and strains of steel-wire mesh were measured during the course of the test, and performances of the beams are compared and assessed with particular emphasis on cracking behavior, mid-span deflection, ultimate strength capacity, modes of failure and so on. The results showed that the ferrocement contributes obviously to the increase of load-bearing capacity, raises the crack-resisting capacity and improves the bending stiffness of RC beams. Based on plane cross-section assumption, the theoretical ultimate strength capacity results of beams are obtained and show a good agreement with the experimental results of the tested beams.