Determination of optimum volume proportions for Sarooj (Pozzolan) lime mixes

Sarooj is an artificial pozzolan produced by burning special types of clays. It has been used extensively in Oman as a cementing material in concrete masonry construction, particularly in hydraulic structures, buildings and military installations. Sarooj is cementitious when mixed with lime and water. It is a cheap cementitious material for use in construction and restoration of historical buildings. An experimental research program was developed to determine the optimum volume proportions that can be used in concrete and mortar mixtures. Twenty five sarooj-lime mixes having different proportions of sarooj, lime, sand and water were tested. In addition, two groups of mixes (sarooj, lime, sand, water) batched by weight and by volume, with each group contained three mixes of the same proportions, were tested to study the effect of the fineness of sarooj on the strength characteristics of the sarooj-lime mix. It was found that grinding sarooj to pass the 300 μm sieve produced the highest compressive strength, while optimum volume proportions of sarooj, lime, sand and water for the highest compressive strength was 3:1:3:1.9.