Determining ASR characteristics using dilatometer method

Abstract Alkali–silica reaction (ASR) is a major durability problem in concrete leading to premature deterioration of different types of concrete structures. Current laboratory tests are largely simulative in nature and yield mainly empirical results, and users state that there is little relationship between the test, the results and actual field performance. A different approach is necessary. This paper is part of a broader research study to assist owners, engineers, and contractors to identify and quantify the potential for concrete pavement deterioration, as a result of ASR. To achieve this objective, a comprehensive study on concrete and mortar mixtures using different types of aggregates of different reactivity was conducted to formulate a reliable and timely testing protocol. A kinetic model was proposed to predict ASR characteristics which were calculated using the system identification method. From test results, it was determined that the proposed testing approach provides direct accountability for various factors affecting ASR, such as aggregate reactivity, calcium concentration, presence of fly ash, and solution alkalinity. Chemistry of the alkali solution validates the laboratory research findings.