Abstract: A hydrated cementitious blend, and method of using same, the blend comprising: a dry cementitious blend comprising the following, based on the total weight of the dry cementitious blend: aggregate comprising less than 3 wt. % calcium, based on the total weight of the aggregate; from about 75 wt. % to 82 wt. % pozzolonic material comprising improved ash comprising particles meeting the ASTM C 989-2010 testing protocol for grade 100 slag quality or higher, the improved ash being selected from the group consisting of fly ash, calcined or uncalcined volcanic ash, rice hull ash, and combinations thereof; a catalytically effective quantity of catalyst selected from the group consisting of alkali-containing zeolite, alkali-containing feldspathoid, and combinations thereof; and, an amount of water reducing component; the hydrated cementitious blend further comprising an amount of water producing a ratio of water to cementitious blend of from about 0.20 to about 0.