• Iskhakov, Tagir
• Meschke, Günther
• Timothy, Jithender J.

Abstract

<jats:title>Abstract</jats:title><jats:p>ASR is a microscopic process in concrete characterized by the formation of a hydrophilic alkali‐silica gel due to the reaction of the alkali in the pore‐fluid with silica in the aggregates. In the presence of moisture, the gel swells and induces an internal pressure that leads to microcracking, expansion and overall deterioration of the material. When subject to external alkali supply, the material is susceptible to higher levels of degradation. Transport of alkali ions at the structural scale in partially saturated concrete is modelled by coupling the diffusion equation with the Richards equation for moisture transport. The overall deterioration of concrete pavements due to ASR can be modelled by a synthesis of two sub‐models: 1) the alkali concentration is coupled to a meso‐scale reaction model describing the formation and evolution of the alkali‐silica gel; 2) the gel induced microcracking in the material is estimated using a semi‐analytical multiscale micromechanics model [1]. The model capabilities are evaluated using selected numerical examples and comparisons with experimental observations.</jats:p>

Topics

• impedance spectroscopy
• pore