Determination of fracture toughness and indirect tensile strength for a polymer concrete (PC) material using an experimental method

An experimental method was used for obtaining fracture toughness (KIc) and the indirect tensile strength (t) of the chopped strand glass fiber polymer concretes (PC) material using disc shape specimens. Circular disc shape specimens subjected to diametral compression (often called the Brazilian disc) were used for conducting the experiments on the PC material. While the center cracked Brazilian disc specimen could be used to evaluate fracture toughness, the tensile strength was obtained from the un-cracked Brazilian disc specimen indirectly. The experiments showed the practical applicability of both cracked and un-cracked circular shape specimens for using as suitable techniques for measuring KIc and t in polymer concretes. The average values of t and KIc of tested PC were 1.5 MPa m0.5 and 8 MPa, respectively. Furthermore, a comparison of test data obtained for the tested polymer concrete and ordinary cement plain concrete using the same Brazilian disc specimens demonstrated that the average tensile strength and fracture toughness of the tested PC is approximately 3 to 4 times the corresponding values obtained for plain concrete showing the improved strength properties of polymer concrete relative to the plain concretes.