Environmental impacts on expansion of concrete due to alkali-silica reaction

摘要

Environmental conditions critically affect the expansion behaviour of concrete due to alkali-silica reaction (ASR) and, therefore, must be modelled to predict ASR-induced expansion behaviour. In addition, laboratory tests are important for the provision of useful data for numerical models, since these models often require the calibration of some unknown parameters according to the materials tested. To address this, the authors have developed a testing method for concrete expansion, called the alkali-wrapped concrete prism test (AW-CPT). Predictions using the results of the AW-CPT would be beneficial for the assessment of potential expansion of concrete when exposed to the outdoor environment. In this study, the effects of environmental conditions on ASR-induced expansion behaviours are determined through exposure and laboratory tests. The environmental conditions are modelled and implemented in numerical simulations. The results indicate that solar insolation and rainfall are critical parameters for modelling the environmental conditions as well as ambient temperature and relative humidity.