Cyclic Behaviour Of RC Rectangular Concrete Column Strengthened With CFRP Composites

Since the early 1990 s, a large number of research has risen continuously on the monotonic of concrete columns externally jacketed with FRP composite wraps, including both experimental and analytical studies. A slightly growing number of studies have recently concentrated, in contrast, on the cyclic behavior of small and medium-size concrete columns confined with fiber-reinforced polymer(FRP) sheets. However, most of the up-to-date literature on the behavior of FRP-confined compression members has focused extensively on square and circular unreinforced(plain) concrete columns. In fact, it is well known that the dominant structural buildings RC columns are rectangular, and the studies have clearly revealed that the behavior of these columns mainly depends on several factors such as aspect ratio of cross-section, confining reinforcement, sharpness of the section corners, etc. According to the literature, research on the influence of side-aspect ratio, height, larger crosssection, and ratio of internal steel reinforcement on the behavior of axially cyclic loaded rectangular reinforced concrete columns confined with CFRP composites is, however, very limited. To address such knowledge gaps, this paper presents a pilot research providing a comprehensive pool of laboratory testing results of 42 large-scale RC columns tested under monotonic and cyclic compressive loads after being strengthened with carbon fiberreinforced polymer(CFRP) composites. The experimental study deals with a series of tests to consider the primary test variables: namely, cross-sectional aspect ratio, internal hoop and longitudinal steel reinforcement ratio, number of layers of CFRP sheets, and different loading pattern(i.e., monotonic and cyclic). In coluction of the current research, the test results revealed that there is an influence for the considered parameters on both of the cyclic and monotonic response of concrete columns.