Canada: Dalhousie University, in collaboration with the Canada and US joint Gypsum Association and Divert NS, has entered Phase 2 of its research project into uses of construction and demolition waste gypsum in concrete. The research, continuing until September 2023, will test the durability of various concrete mixes containing gypsum powder recycled from waste drywall. It will examine 81 specimens under three environmental exposures and three exposure durations. The team will use the results to understand the performance and environmental benefits of concrete containing recycled gypsum over the life of a structures. Study leader and Canada research chair in sustainable infrastructure Pedram Sadeghian said that Phase 1 of the study had demonstrated that gypsum could be a viable supplementary cementing material when combined with fly ash in concrete.
Sadeghain said “Our research group aims to study the durability of concrete containing recycled gypsum by monitoring compressive strength and potential expansion after exposure to selected environmental conditions, such as moisture and salt particle penetration, that are common to concrete structures exposed to the environment.”
Gypsum Association executive director Stephen Meima said “The gypsum industry is committed to landfill diversion of construction and demolition gypsum panel waste, and Professor Sadeghian’s work demonstrates that waste gypsum panels may have value beyond their service life in buildings and homes.”