Sustainable Paving Blocks from Fly Ash: An Innovation for the SDGs

Wibowo, Sekarsari
Cahyono, Luqman
Khaqiqi, Alwi Sina
Rahayuningsih, Siti
Al Hazman, Muhammad
Kusuma, Dwi Mahendra
Ridwansyah, Moh. Farikh Tirta

Civil and Environmental Science Journal (CIVENSE)
Vol. 8 No. 2 (2025)

This study determined the optimal proportion of fly ash as a partial replacement for Portland cement in paving block mixtures to maximize compressive strength while supporting sustainability. Three fly ash substitution levels (10%, 20%, and 30% by cement weight) were evaluated. All mixtures met the K-300 standard (≥30.6 MPa), but the 20% substitution proved optimal, yielding the highest average compressive strength of 37.2 MPa with the lowest variation (CoV of 5.8%). The incorporation of fly ash also enhanced physical properties by reducing water absorption and porosity. The findings validate the use of fly ash for producing high-performance, environmentally friendly paving blocks that meet stringent quality standards.