Study On Seismic Behavior Of The Injury R.C Column Strengthened With CFRP Sheets And Angle Steel

In recent years, the earthquakes broke out frequently,so that many of the houses in the areas of earthquake were damaged in varying degrees. Among them, many of reinforced concrete frame buildings were damaged mainly in the bottom of column. After strengthened appropriately, they may be used continue. There are many ways for strengthened, the method of compound strengthened by CFRP sheets and angle steel was studied by some scholars, and the result indicates that it combines the advantages of two materials and can also increase the bearing capacity and deformation of the frames. But the seismic performances of damaged R.C columns strengthened by CFRP sheets and angle steel are studied. In this artical, four injured RC columns were strengthened by CFRP sheets and angle steel, and then the seismic performances are studied, the main contents are as follows:Four RC columns with varying degrees of damae were strengthed bwith CFRP sheets and angle steel. The amount of CFRP strengthened for the four columns were the same, only consider the changes in the amount of angle steel. Angle steels were strengthened on the columns bottom by structural adhesive and anchor. The experiments are done under low-cyclic and repeated load which was applied by the level of hydraulic actuator, in the course of experiments load, the displacement, cracks, angle steel and CFRP strains were record. Based on test results, the skeleton curve and hysteresis loop of the specimens were drawn out, and the seismic performances of the strengthened columns about different limb lengths and limb thicks of angles steel are studied. The results show that the injury R.C columns were composited strengthened by CFRP hoops and angle steels with a better capacity. The longer angle steel's limb is, the higher the capacity of the composited strengtnened column. But it wasn't influence for the limb's thickness. The columns composited strengthened possess a good seismic performance.Finally, according to test results, the flexural capacity formula of composited strengthened column is derived, which takes into account the strength of CFRP and angle utilization, and damage coefficient. The calculating results were in good agreement with the experimental results. And meet to the reliability of ductile member. It could provide the basis for practical engineering reinforcement.