Volcanic Ash

Volcanic ash refers to volcanic fragments with particle size less than 2 mm, formed when magma is violently fragmented and rapidly cooled during volcanic eruptions. It consists of fragments of volcanic glass, mineral crystals and rock debris, rather than ash from combustion. Core property: rich in amorphous volcanic glass and possessing pozzolanic activity (pozzolanic effect). In the presence of water, it can undergo hydration reaction with calcium hydroxide to produce cementitious substances, which is the fundamental principle for its application as a supplementary cementitious material.