Study On Sheer Behavior Of Concrete Column Strengthened With Carbon Fiber Reinforced Plastic Sheet Under Low Cyclic Level Load

Construction function is unfit for the requirement of safety, applicability and durability because of the effect of many factors of design misplays, aging, material's quality defeat, earthquake disaster. It has received significant attentions in civil engineering on how to widely using existing structures, performance its normal functions and attaining the economical aim. Based on the research and analysis, strengthening the defeat structure is one effective method for the question.Now, there are many strengthening methods for structure. In recent years, the technology of CFRP confining concrete structure has rapidly developed in international and domestic engineering. It has received extensively attention in civil engineering due to their unique properties, such as high strength-to- weight ratio, good resistance to corrosion and fatigue, convenient to construction, no additional weight and dimension. In this paper, experimental study has been done on confining concrete column's properties with CFRP under low cyclic loads. The following works have been done:1 Twelve specimens have been made, which considered the parameters influence of the amount of the CFRP, stickup fashion, span ratio and force-axis ratio.2 The failure fashions and experimental performance have been described. The failure fashions have three patterns: sheer destroy, sheer - flexural destroy and flexural destroy. The destroy reasons have been considered in the paper.3 Based on the experimental date analysis, hysteretic curves of load-displacement, skeleton curve and load-stress curves have been given to investigate the transformation rules of those curves under the influence of different parameters. With the adding of CFRP amount, the area of hysteretic curves becomes bigger and chubbier and there is a remarkable improvement in sheer capability and ductility of the concrete column confined with CFRP. With the force-axis ratio adding, the sheer capability of the confined columns has an improvement. But the sheer capability of the confined columns becomes lower with the decreasing.The mechanism of the concrete column confined with CFRP has been studied in this paper. According the material relationship of strain-stress, a reasonable shear capability design formula is presented based on the typical truss mode. Compared with the experimental dates, the calculating results are safety, and can be referenced in engineering practice.