Durability of Recycled Glass Sand (Concrete 2021)

This webinar was recorded at Concrete 2021 and the speaker is Simon Murcott from Boral.
Laboratory and field assessment carried out by Boral and Roads & Maritime Services, NSW (RMS) have concluded that recycled glass sand could be successfully incorporated in concrete pavements. There are some concerns regarding the long term durability of concretes using recycled glass sand in bridge constructions. Coarse and medium grained recycled glass sand was used in this investigation as partial replacement of natural sands in concrete. The mix design used in the assessment was as per RMS requirements for concretes used in bridge constructions, under B2 exposure classification. Four concrete trial mixes (control, plus 3 concrete mixes with 10%, 15% and 20% recycled glass sand as natural sands replacements were carried out. The concrete was assessed for compressive strength at 1, 3, 7, 90, 180 and 365 days under three curing conditions: (1) standard wet curing, (2) 28 days wet curing followed by air curing and (3) 28 days wet curing followed by coating with curing compounds (CC). Concrete durability was assessed using (a) chloride migration test as per NT492 at 28 days, (b) chloride diffusion coefficient as per NT443 after 56 days wet curing, (c) surface electrical resistivity as per AASHTO T358 test method after wet curing up to 365 days and (d) alkali silica reaction (ASR) by the accelerated test method AS 1141.60.1 (recycled glass only) and by concrete prism test (AS 1141.60.2) for concrete.