Simulation of Damage Due to Alkali–Silica Reaction in a Concrete Model at the Macroscale Level

Abstract

The rapid deformation caused by alkali–silica reaction may cause major problems in concrete structures. Main factors that affect ASR include the relative humidity, alkali and silica content, temperature, and porosity of the concrete. The vast numbers of influencing factors make ASR relationship a complex phenomenon to understand. Investigation of the mechanical deformation of the structure can be achieved by applying the theory of continuum damage mechanics. Prediction of the physical and chemical behavior of a structure can be achieved using damage mechanics, making it an appropriate method to study the behavior of the structure under the influence of alkali–silica reactivity. Hence, solution of the damage model as well as simulation of the ASR phenomenon is critically needed. In this research, an engineering example of a thermo-chemo-hygro-mechanical model of a concrete gravity dam at the macroscale will be studied for varying environmental conditions of temperature and relative humidity using the finite element method. Investigations found that temperature as well as relative humidity influences the latency and characteristic time constants, which indicates that the ASR expansion rapidity is dependent on the heat and moisture diffusion lengths into the structure, causing heterogeneous damage along the cross section of the macroscale structure according to the temperature distribution as well as relative humidity.