The Study On The Developing Law Of Crack In FRP Compound RC Structure

FRP compound RC structure is designed as one new type of RC structure based on crack-resistence mechanism of fracture mechanics.By means of"retarding"crack controlling method,this kind of new structure applied the excellent mechanical properties of FRP into the design of RC structures.Based on the fundamental priciples of fracture mechanics and its crack-retarding mechanism in FRP compound RC structure,this papers has analyzed and summarized the developing law of crack in FRP compound RC structure on the process of loading.This paper's researching focus and conclusions includes:Firstly,based on two fracture mechanisms of linear elastic fracture mechanics,analyzed the mechanics of crack-retarding & Reinforcing of FRP and steel between the FRP compound RC structure and RC structure,and we has compared the two types of structure with the capacity of bettering crack.Secondly,established the structure model of concrete structure,RC structure and FRP compound RC structure by FEM,analyzed the function of retarding crack of FRP compound RC structure in conditions of different crack height and loadings,according to the change of stress intensity factors in the crack tip.then analyzed FRP compound RC structure's capacity of bettering crack in comparison with RC structure according to the numerical results.Thirdly,based on the bended test of beam structure,the study has summerized that the cracks in FRP compound RC structure have four stages of development with the increasement of loading,and studied the changing law of the crack distribution patterns,crack width,crack height,crack distribution areas in different stage of development.Further more,testified the excellent capacity of crack-controlling of FRP compound RC structure in comparion with the law of distribution of crack in RC structure.