Polyester polymer concrete modified by polyester fibers and gamma rays

As is well-known, polymer concrete is manufactured by mixing a thermosetting resin, such as polyester, and mineral aggregates, such as silica sand and marble. Such concrete presents low levels of ductility, and its load -bearing applications are limited, which suggests using reinforcement materials as fibers for improvement. However, it is not common to add polymer fibers, since sometimes the mechanical performance decreases. Thus, polymer fibers need some kind of physical or chemical modification. One alternative consists of using high ionizing radiation, such as gamma rays. For these reasons, in this work, polyester fibers were added to polymer concrete produced with 30 wt% polyester resin and 70 wt% marble. Afterwards, concrete specimens were irradiated with gamma rays. Three marble particle sizes were used (7.1x10-3m, 14x10-3m and 23.6x10-3m), three fiber contents (0.1, 0.3 and 0.5 wt%) as well as three radiation doses (50, 100 and 150 kGy). Improvements of up to 35 % in the deformation, 29 % in the elasticity modulus and 10 % in the compressive strength, were obtained for irradiated concretes with polyester fibers. These mechanical features were related to the modifications produced by gamma rays on the marble crystallinity, as well as the surface, chemical structure, and hydrophi-licity of the polyester fibers.