  The alkali-silica reaction (ASR) in concrete is a chemical reaction, which
produces an expansive product, generally called ''ASR gel'', and causes
cracking and damage in concrete over time. Affecting numerous infrastructures
all around the world, ASR has been the topic of much research over the past
decades. In spite of that, many aspects of this reaction are still unknown. In
this numerical-investigation paper, a three-dimensional concrete meso-structure
model is simulated using the finite-element method. Coarse aggregates, cement
paste, and ASR gel are explicitly represented. A temperature dependent
eigen-strain is applied on the simulated ASR gel pockets to capture their
expansive behavior. This applies pressure on the surrounding aggregates and the
cement paste, leading to cracks initiation and propagation. Free expansion of
concrete specimens due to ASR is modeled and validated using experimental data.
Influence of different key factors on damage generation in aggregates and paste
and macroscopic expansion are discussed.
