THEORY OF THE STATISTICAL CONSTITUTIVE MODEL OF STRAIN RATE DEPENDANCE OF THE FIBER AND ITS EXPERIMENTAL STUDY

According to the classical fiber's statistical strength and some hypotheses,the statistical constitutive models of the rate-sensitive fiber and fiber bundle are set up,and the corresponding constitutive equations are deduced.The method to determine the mechanical parameters in the constitutive equations of the rate-sensitive fiber by the tensile impact test of the fiber bundle are proposed from such models.The tensile experiments of the E-glass fiber bundles are performed under the strain race of 10^-4-10⁸ l/s in order to examine the validity of the test models and its test method. The test results and its analysis show that the hypotheses of the models are correct an d the test method is practical. Such models explain successfully the mechanical behaviors of fiber under the strain rate of 10^-4 1.1×10⁸ l/s.