Significance of performance based specifications in the qualification and characterization of blended cement using volcanic ash

Blended cement has become an essential requirement for producing high-performance concrete as it promotes sustainability in construction by decreasing the carbon foot print and enhancing the durability of concrete structures in the aggressive environments. A systematic study for the qualification of volcanic ash (VA), and for the laboratory-scale preparation and characterization of blended cement according to international standards and specifications for evaluating the potential of using regionally available VA in blended cement is discussed in this paper. Binary cement blends were prepared in the laboratory by replacing cement with VA in four different percentages by mass of the blended cement, and its performance was evaluated. The physical and chemical properties of blends were investigated and were compared with the allowable limits prescribed in international standards. The compressive strength of the blends with the VA content varying from 10 to 30% satisfied the limits specified in ASTM C595 and ASTM C1157. Finally, guidelines were developed for using regionally available VA as a natural pozzolana for producing blended cement.