Simulation of mixed-mode fracture (I-II) on PFRC specimens with various fibre proportions using an embedded cohesive crack model

FIBRE CONCRETE 2019

土木建筑工程

Suárez, F.^1 ; Gálvez, J.C.^2 ; Enfedaque, A.^2 ; Alberti, M.G.^2

Departamento de Ingeniería Mecánica y Minera, Universidad de Jaén, Campus Científico-Tecnológico de Linares, Avda. de la Universidad (Cinturón Sur), Linares, Spain^1

Departamento de Ingeniería Civil-Construcción, Universidad Politécnica de Madrid, E.T.S.I. Caminos, Canales y Puertos, C/Profesor Aranguren s/n, Madrid, Spain^2

关键词: Cohesive crack modeling;    Combination of modes;    Concrete components;    Different proportions;    Fibre reinforced concrete;    Mixed mode fracture;    Strength of concrete;    Three-point bending test;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/596/1/012007/pdf
DOI  :  10.1088/1757-899X/596/1/012007

学科分类：土木及结构工程学

来源: IOP

【 摘 要 】

The study of fibre-reinforced concrete (FRC) has become of increasing interest in the last decades. Although it is not a new technology, it has experienced a remarkable progress with the appearance of some recommendations in the standards. More specifically, the use of polyolefin fibres has proved to increase the tensile strength of concrete without the problems usually found with steel fibres, especially those related to corrosion. This type of fibres have been studied in depth and its fracture behaviour has been successfully simulated in the past by means of an embedded crack model using a trilinear softening function. Nevertheless, these simulations have been always focused on cases where fracture took place under pure mode I conditions, namely using the classical three-point bending test on notched specimens. In this study, such embedded crack model is used to reproduce the fracture behaviour on notched specimens subjected to a modified three-point bending test that induces fracture under a combination of modes I and II. Three PFRC mixes are analysed, all of them with the same proportions of concrete components but different proportions of polyolefin fibres. The experimental and numerical diagrams properly agree and allow identifying how the increasing proportion of fibres can be reflected in the trilinear softening function that numerically drives the damage evolution.