A chemo-mechanical modeling of Alkali Silica Reaction (ASR) was proposed in the view of
mesoscale and introduced to finite element analysis. Chemical reaction between alkali components and alkaline reactive minerals in aggregate, producing of a hygroscopic gel and swelling of the gel were simply modeled. Moreover, transportation of both alkali ions and moisture content in concrete was also
evaluated by considering the nonstationary diffusion equations in the analysis. Parametric analyses with single aggregate model were conducted in order to confirm the applicability of the proposed model. As
the results, it was shown that the proposed model was useful to evaluate ASR expansive behavior, since effects of alkali content and humidity on ASR were simulated qualitatively.