Title:
Plastic-Fracture Stress Transfer Model for Concrete Discontinuities
Author(s):
Zhishen Wu, Ahmed M. Farahat, and Toda-Aki Tanabe
Publication:
Materials Journal
Volume:
91
Issue:
5
Appears on pages(s):
502-508
Keywords:
aggregates; cracking (fracturing); mortars (material); stress transfer; surface defects; Materials Research
DOI:
10.14359/4079
Date:
9/1/1994
Abstract:
A physically based constitutive model for the behavior of concrete discontinuities is proposed. To consider a detailed mechanism that expresses the microscopic features of concrete discontinuities, the crack surface is idealized with both sawtooth and circular asperities. The sawtooth asperities represent the contact between mortar and mortar, while the circular asperities are used to simulate the phenomenon of aggressive interlock (i.e., contact between aggregate and mortar). The behavior of the two types of contact is investigated. To simulate all possible kinds of nonlinearities, two independent hyperbolic surfaces with a Mohr-Coloumb surface as an asymptotic surface for both the plastic potential and yield function are defined in stress space. Basic material parameters such as cohesion, internal friction angle, dilatancy angle, and tensile strength are varied according to the accumulated damage at the crack interface. Finally, several paths are considered to evaluate the capability of the proposed model. The model is amenable to implementation in such numerical procedures as finite element computer programming.