2.3. Testing and Characterization

X-ray diffraction (Smart Lab, Rigaku, Tokyo, Japan) analysis was used for the composition of the self-made cement without K⁺, Na⁺, and Mg²⁺ and the composition of dolomitic rocks. The length changes of all specimens prepared by different aggregates were measured at different ages and the expansion ratio of all the specimens were calculated by the abovementioned formula. Each length change value used was the mean value of three replicate specimens. The morphologies of aggregate grains enriched dolomite selected from the microbars cured in TMAH solution were also observed by SEM (JEOL, JEM-6510, Tokyo, Japan) coupled with EDS analysis. Orthogonal polarized light microscopy (DM750P, Leica, Germany) was also used to investigate the cracks as a result of ACR.