Experimental And Design Method Study On Strengthened Flexural And Shear Of Steel Beams With Near Surface Mounted CFRP-PCPs

In this study, the feasibility of using CFRP prestressed concrete prisms(CFRP-PCPs) as reinforcement to address the aforementioned problems will be presented. CFRP prestressed concrete prisms(CFRP-PCPs) are bars of small cross section made with high strength concrete and concentrically pre-tensioned by a single CFRP bar. Due to the effect of prestressing, using CFRP-PCPs as reinforcement can delay cracking of CFRP-PCPs reinforced concrete flexural elements, decrease deflection, and reduce crack widths under the service load.These bars can be used as reinforcement in concrete structures, and can be used as strengthening reinforced concrete members with near-surface mounted, namely a new type of Concrete Construction with CFRP Prestressed Concrete Prisms is formed.An experimental study and the corresponding theory analysis are conducted to investigate the behavior of strengthening of steel beams with CFRP-PCPs reinforcement.This dissertation involves the following work:(1) The material, production instrumentation and process research of CFRP-PCPs reinforced is conducted. We succed in developing production of CFRP-PCPs reinforcement.(2) Six steel beams strengthened with CFRP-PCPs reinforcement have been tested with load. Comparing with plastering CFRP to strengthen prestressed, the technique to strengthen concrete beams with near-surface mounted CFRP-PCPs reinforcement has specialties as follows: while the element is in breakage, the level of CFRP stress increases obviously with the more increment of ultimate camping capaciy of the strengthened element. The performances of the strengthened element at the state of normally using, such as its rigidiy.(3) The breakage forms of bending element strengthened with near-surface mounted CFRP-PCPs reinforcement have been sorted. The strength theory and judgment of wreck in compressive, or tensile have been set up. In addition, methods for determining crack resistance, deflection of strengthening steel beams with CFRP-PCPs reinforcement are suggested.Test results and studies obtained in this paper can provide scientific principles for design specifications and applications of strengthening steel beams with CFRP-PCPs reinforcement.