The Experimental Research Of Strengthening The Negative Flexural Area Of RC Beams With CFRP

As a new structural engineering material, continuous carbon fiber sheet (CFS) has many advantages of excellent mechanical strength and deformation property, convenience in use, low weight, non-dimensional increase, and immunity to corrosion. The CFRP-strengthening technique has attracted many researchers and engineers in the world. So far, this CFRP is one of the high-tech material which is the earliest applied in the civil engineering, the most well-rounded in the technique and the largest in the amout. Compared with other FRP material, the CFRP is the same with the civil engineering fields.Based on the predecessors' work, this paper presents the strengthening effect with two different sticking manners, failure modes, strengthening mechanism and compares the three calculation methods of the ultimate flexural capacity of 8 RC beams strengthened with CFRP in the negative flexural area.Experiments results proved that it is effective strengthening the negative flexural area of RC beams with CFRP. And, the strengthening effect of the second CFRP sticking manner excels the first manner. At the same time, the strengthening mechanism of RC beams in the negative flexural area is the same with in the positive flexural area. So in this paper,the strengthening calculation methods of the positive flexural area is applied in the negative flexural area. Compared wih the three different calculation methods of the ultimate flexural capacity, the method in the #《technical code for strengthening concrete structure with fiber reinforced polymer》 edited by the construction and supervisement committee of shanghai is reasonable and credible. This method may applied in the actual strengthening design.