A new performance test method for alkali-silica reaction

Author(s): Edward Moffatt, Michael Thomas, Michael Laskey
Paper category: Proceedings
Book title: Proceedings of the International Conference on Sustainable Materials Systems and Structures (SMSS2019) Durability, Monitoring and Repair of Structures
Editor(s): Ana Baričević, Marija Jelčić Rukavina, Domagoj Damjanović, Maurizio Guadagnini
ISBN: 978-2-35158-217-6
e-ISBN: 978-2-35158-218-3
Publisher: RILEM Publications SARL
Publication year: 2019
Pages: 160-167
Total Pages: 813
Language: English

Abstract: Current standardized tests methods for identifying alkali-silica reactive aggregates cannot be used as performance tests to determine the risk of damaging reaction of a specific combination of materials or “job mixture”. This paper presents data for a new test that aims to provide a continuous supply of external moisture without either augmenting or reducing the alkalis in the concrete (job) mixture under test. Concrete cylinders are stored in cylindrical containers with a slightly larger diameter such that there is a small annulus of 1 to 2 mm around the concrete specimen. This annulus is filled with a “model pore solution” which is determined based on the composition of the binder in the job mixture. The sealed containers are then stored at either 38°C or 60°C and the length-change of the specimens is measured periodically. Results are shown for a wide series of mixtures using combinations of materials that have been previously used to produce concrete blocks for storage on outdoor-exposure sites; consequently there are long-term field-performance data for the mixes under test. The results show that the new test method is better able to predict the performance of the job mixtures than existing tests. A number of modifications are proposed for future testing.

Online publication :2019
Publication type : full_text
Public price (Euros) : 00