Influence of water repellent chemical additive and different curing regimes on dimensional stability and strength of earth bricks from termite mound-clay

Abstract

This article is focussed on evaluating the effects of water repellent admixture and different curing regimes on characteristics of clay from termite hills used for production of earth bricks. Water absorption, thickness swelling and compressive strength characteristics of the specimens with different compositions of cement, hydrated lime and water repellent additive subjected to different curing regimes were measured. The samples were characterised by SEM and FTIR. The least water absorption was at 3.3% while thickness swelling ranged from 0.78 to 3.21 % for the samples. Saturated curing condition resulted in an average compressive strength of 35.5 N/mm2, cured curing recorded an average value of 32.9 N/mm2 while dry curing condition produced an average compressive strength of 26.9 N/mm2 and the wet curing condition resulted in 25 N/mm2. SEM characterisation of sample containing 70% termite soil, 30% cement and 0.05 Hydropruf indicated fewer voids, regular and smooth appearance in comparison with others. FTIR analysis showed distinctive broad bands at wave numbers of 3439 cm−1 for O-H stretching, and 1033.83–1008.80 cm−1 for O–H bending for all samples tested. The best performing composition in terms of the dimensional stability test was 70% termite mound clay, 10% cement, 20% hydrated lime and 0.05 Hydropruf additive. The highest mechanical strength was from composition of 70% termite mound clay, 30% cement, no hydrated lime and 0.05 Hydropruf additive. It is concluded that saturated and cured method showed better performance than the wet and dry curing regimes. The termite secretions similarly improved the clay composition in conjunction with cement, lime and chemical admixture in the internal structure of the bricks.

The utilization of bentonite enhanced termite mound soil mixture as filter for the treatment of paint industrial effluent

“…Mounds otherwise known as termitaries are structures built by dissimilar termite species from surrounding soils through the redistribution of soil organic matter and elements in their biomass and organo-mineral constructions. They possess low thermal conductivity, resistance to moisture penetration, comparative compressive strength and mostly found in tropical and subtropical geographical environments [14][15][16][17]. Termitaries have been classified as nuisance to agricultural farm lands and wooden infrastructure because of the space occupied and their destructive nature [18].…”

Alkali activation of compacted termite mound soil for eco-friendly construction materials

“…In the termite's mounds, temperature and gases appear to be regulated therefore the interest of engineering these soil structures for sustainable and green construction. Investigations carried by [ 11 ] on termite's mounds clay showed that the use of water-repellent chemical contributed to reducing the water absorption level. In their investigation they used hydrated lime and silane/siloxane as additive to the Termites mounds clay.…”