Geopolymerized self-compacting mud concrete masonry units

Abstract

This study was conducted to develop an alternative method of utilizing fly ash as an alternative stabilizer to build affordable earth masonry units named “mud concrete blocks”. Mud concrete masonry block is a novel invention in which the mud helps to self-compact the mixture to reduce the production of energy content. This study uses fly ash from electric power generating plant with an alkaline solution made of Sodium hydroxide and Sodium chloride. Different combinations of mixtures (fly ash, sodium chloride, sodium hydroxide and soil) were taken into consideration to study a suitable mix design. And compressive strength was tested to understand each mix suitability.

Results of this study have manifested that suitable mix is to use Fly Ash 20% of the dry weight of soil, Sodium hydroxide 5% and Sodium Chloride 2% of the total dry weight. The suitable water ratio is 15%–20% of the dry weight. And then the suitable soil mix proportion was developed. It was found that the soil mix proportion of Gravel 10–20% (sieve size 4.25 mm ≤ gravel≤ 20 mm) range of (35%–45%), the Sand 70–80% (sieve size 0.425 mm ≤ sand ≤4.25 mm) proportion of (60%–70%) and Fine ≤10% (≤sieve size 0.425 mm) content of 5% makes the best mix to develop. Scanning electron microscope images were taken to understand the geo polymerized fly ash bond result on the total strength of the soil mixture.