Fracture toughness measurements of polymer concretes

Abstract

SYNOPSIS This paper describes the use of linear elastic fracture mechanics to examine the behaviour of premix and impregnated polymer concretes. Results are given for three monomers, viz. styrene, methyl methacrylate and butyl methacrylate, and two strengths of concrete, as well as for appropriate control series. The notched-beam technique is used to determine fracture parameters, together with compliance measurements to determine slow crack growth. Experimental results indicate that thermal treatment to polymerize the monomer in the premix concrete has a marked influence upon fracture toughness. Irradiation on the other hand has little influence. Polymer impregnation increases the stress-intensity factor and the strain at failure, the latter increase being influenced by the extensibility of the polymer. The results also show that the plain and the premix polymer concretes are partially notch-sensitive, whereas the impregnated polymer concrete is a notch-sensitive material.