Development of indigenous binders as construction materials Available to Purchase

Strategies were devised for the development of cementitious binders using abundantly available indigenous raw materials. These strategies emphasise the simple processing of raw materials using locally available resources. The raw materials selected for the development of indigenous cementitious binders included volcanic tuffs, laterite soil, soda ash and natron. Two classes of indigenous cementitious binders were developed and characterised. They were based on (a) volcanic tuffs transformed into calcium aluminosilicate hydrate binders using lime and soda ash and (b) laterite soil activated with soda ash and lime, using moderately calcined laterite soil as partial replacement for natural laterite soil, where alkali aluminosilicate hydrate and calcite provide the primary binding effects. Various formulations embodying these two strategies were prepared and subjected to early-age compression tests. The resulting inorganic binders were further investigated using scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction methods. The results of these analyses verified the intended chemical and mineralogical compositions of the indigenous binders.