无限域考虑桥联影响的反平面裂纹动态扩展

在考虑与裂纹面位移成正比的桥联力影响下，对无限大纤维增强复合材料中半无限长反平面裂纹的动态传播进行了讨论．利用Fourier变换，问题简化成一个方程，利用Wiener-Hopf技术进行了求解．得到的应力强度因子可以表达成一个速度修正因子与静态应力强度因子乘积的形式．结论有：(1)由材料性能决定的音速是裂纹传播速度的上限；(2)桥联纤维在增韧复合材料和组织裂纹扩展中起了关键作用；(3)受桥联纤维力作用的半无限长裂纹在无限域中扩展等效于半无限长裂纹在带域中扩展．

Dynamic fracture of anti-plane crack with consideration of fiber-bridged in composites

A semi-infinite anti-plane dynamic crack propagating with constant velocity in infinite fiber-reinforced composites is discussed with consideration of the fiber-bridging tractions which are related to the displacement of the crack surface. With the use of Fourier transforms, the problem is reduced to an equation which is solved by the Wiener-Hopf technique. The dynamic stress intensity factor is derived and is expressed as the product of a velocity correction factor and a static stress intensity factor. The conclusions are: (a) The sonic velocity determined by the material's properties is the upper limit of the crack velocity; (b) Bridging fibers plays a key role in increasing the composite's toughness and stopping the crack's propagation; (c) The semi-infinite crack propagating in infinite region with the fiber bridging traction action is equal to the semi-infinite crack propagating in strip.