Improvement of gypsum plaster strain capacity by the addition of rubber particles from recycled tyres

This paper shows the results of a research project to valorize rubber waste from end-of-life tyres (ELTs). The aim of this study is to improve the elastic behaviour of gypsum plaster by the addition of a highly elastic polymer, such as rubber, so that the elasticity modulus of the resulting compound is smaller than gypsum plaster without additives. In this way, reducing the probability of cracking in the first hours after hardening, due to lack of material elasticity will be possible. This study analyses the mechanical behaviour of gypsum plaster with different granulometries of rubber particles (0–1 mm, 1–2 mm and 2–4 mm), and in different rubber volume fractions (1%, 3% and 5%). The experimental results are compared with results of gypsum plaster specimens without rubber.

► Gypsum plaster with different formats and percentages of rubber has been studied.
► Rubber particles lead to a decrease in mechanical properties of gypsum plaster.
► Mechanical properties obtained fulfil the UNE-EN 13279-1 standard.
► Valorization of ELTs residuals is feasible by incorporating them to gypsum plaster.
► Modified Kraai slabs did not show cracking in gypsum plaster performed.