Modelling of concrete degradation due to alkali - silica reaction in variable hygro-thermal conditions

Durability of cement based materials in normal and chemically aggressive environment has been an important subject of research in recent two decades. Several mathematical models have been developed for predicting the service life of concrete structures. Different chemical degradation processes are considered, including also those due to the Alkali - Silica Reaction (ASR). Most of the models describing the latter process are based on a phenomenological approach. Here a mechanistic-type approach to mathematical modelling of chemical degradation of concrete, based on mechanics of multiphase porous media, due to combined action of hygro-thermal, chemical and mechanical loads, is presented. Then the model has been applied to the concrete degradation due to ASR reaction and the sensitivity analysis of the model for variations of some selected material parameters, has been performed.