Influence of embedment depth on dynamic failure property of twin fibers pull-out test

Abstract

Weibull statistical distribution function is introduced to establish dynamic numerical simulation model of twin fibers pull-out test with the software RFPA^2D (realistic failure process analysis)-dynamics. The model is used to describe the non-uniformity of mechanical properties of concrete materials in different phases and study the influence of embedment depth on mechanical properties under dynamic load. According to the elastic damage constitutive relation of the meso-element, the dynamic tensile failure processes of specimens with various embedment depth are studied from micro-cracks initiation, propagation to crack penetration. The curves of load-displacement and acoustic emission cumulative number curves are also obtained. Influence of the embedment depth on properties of the twin fibers pull-out test specimens is scrutinized. The results show that variation of embedment depth of fibers has significant influence on the failure pattern of the specimen. Under dynamic loading, a phenomenon called 'vibration springback’ appears obviously in specimens with larger embedment depth. In addition, with increasing embedment depth, the twin fibers coupling effect is enhanced and the pull-out process needs more energy, which leads remarkable higher strengthen and toughness.