The Research On Interface Fracture Problems Of Fiber-reinforced Materials

Fiber-reinforced materials have been widely used in the engineering field, and the toughness-reinforced problems of them had been paid greatly attentions by many researchers. So there are important meanings and vast engineering backgrounds to study these problems. Just based on above purpose, this paper makes following jobs.Firstly, using elasticity theory, fracture mechanics and composite materials mechanics, the fundamental equations of fiber-reinforced materials were given. Secondly, with the mechanical model established by Professor Y.C.Gao and the methods of fracture mechanics, the debonding process was treated as crack expanding process. Considering the influence of friction, the initial debonding process between fiber and matrix of fiber-reinforced materials was analyzed and the corresponding debonding criteria was obtained. Lastly, the mechanism of fiber debonding were considered, then the interface completely debonding status and fiber initial pull-out even complete pull-out process had been studied. At the same time, fiber complete debonding force and pull-out stress were obtained, and the influences of fiber bridging effects on the fiber-concrete materials toughness were also given.The results here can provide certain references to design and application of fiber-reinforced materials.