Study of radon emanation from polymer-modified cementitious materials

A growing concern of the scientific community is the environmental impact caused by the increase of by-products from a variety of industrial sectors. A way of diminishing this problem is to employ waste material as an additional element in the formation of construction materials. However, to date, the fact that some of these by-products may increase the uranium content (U-238) of materials and, thus, the emanation of radon (Rn-222), representing a potential risk to human health, is still generally ignored. The purpose of this study is to evaluate the influence of polymers in composites containing vegetable wastes with regard to the emanation of radon, seeking a correlation between the rate of emanation of this gas and the physical-mechanical properties of the material. The cementitious composites were characterized according to the Brazilian standards, ABNT, for mortar tests, while the porous system was analyzed by means of gas expansion porosity and permeability tests. Radon emanation was determined using a solid-state nuclear track detector, LR-115. The results of these tests indicate that the addition of polymer tends to reduce the radon emanation rate of the reference composite.