ガラス繊維強化ポリカーボネート切欠平板の静的破壊特性

Abstract

A fracture criterion based on the concept of linear notch mechanics (LNM) for predicting the failure load of composites containing stress concentrations is subjected to further experimental scrutinization. An experimental program is presented which examines the effect of notch geometry on the fracture of FRP plates. This is accomplished by obtaining experimental data on tension tests and fourpoint bending tests of short-glass-fiber reinforced polycarbonate plates having U-shape notches for a wide range of notch-root radii and depths. The concept of LNM is based on the similarity of the severity near the notch root. The severity near the notch root can be expressed by both the maximum elastic stress σmax and the notch-root radius ρ. On the basis of the concept of LNM the fracture criterion for notched plates is expressed as: σmax=σmax, c(ρ), where σmax, c is the material constant, which is governed by the notch-root radius ρ only and independent of notch geometry and specimen size. The experimental results can be clearly explained on the basis of the concept of LNM, and show that the fracture criterion for notched plates mentioned above is applicable to the material used.