Evolution of Air Permeability of Concrete due to Expansion Caused by Internal Swelling Reactions (ISR)

Predicting and evaluating the transfer properties of concrete affected by Internal Swelling Reactions (ISR) is a main challenge for experts involved in concrete durability testing. The aim of this study is to measure the evolution of air permeability with the development of ISR, for different levels of expansion and various degrees of concrete saturation. In this work, two ISR were studied: the Alkali-Silica Reaction (ASR) where the origin of the swelling is located in the aggregates, and the Delayed Ettringite Formation (DEF) where the origin is located in the cement matrix. The first results obtained show that the development of ISR and induced cracks leads to an increase in the air permeability of concrete, especially in highly saturated concrete. The data of this study make it possible to evaluate the evolution of the transfer properties according to the generated expansion and induced cracking and the degree of saturation of the concrete.