Thermo physical Properties of a Sun Dried Clay Brick Moulded with Cement and Neem Leaves Ash as Additives

Abstract

Neem tree (Azadiractaindica) popularly known as “Dogonyaro” is very common in Nigeria, more especially in the northern part of the country. The problem of the neem leaves waste, make the leaves to be burnt into ashes, however burning the leaves does not solve the waste problem completely. The problem of waste disposal and the cost of cement in the brick molding for building led to this study on the thermophysical properties of clay brick molded with cement and neem leaves ash. The mixture of clay, cement and Neem leaves ash at varying proportion (100% clay, 30% cement, 5%, 10%, 15% and 20% Neem leaves ash) was loaded into a wood mould compartment, manually tamped, leveled, and also shade cured for 5, 13, 19, 26 and 33 days. The results showed that when Neem leaves ash content is 10% (20% cement), the highest average compressive strength of 1.50 Nmm^-2 at 33 curing days was obtained, when Neem leaves ash content is also 10% (20% cement) the highest modulus of the rapture of 0.71 Nmm^-2 at 12 curing days was obtained when Neem leaves ash content is 20% (10% cement), the highest water absorption of 16.1% at 5 days of curing was obtained when Neem leaves ash content is 5% (25% cement) , the highest initial rate of absorption of 1.43 kg m^-2min^-1 at 5 curing days was obtained, when 0% Neem leaves ash (30% cement), the highest density of 2.843 kg. mm^-3 was obtained, also when Neem leaves content is 10% (20% cement) of 2 cm thickness, the highest thermal conductivity of 164.45 wm^-1k^-1 at 6 minutes of 26 days was obtained. This shows that Neem leaves ash as partial replacements of cement in clay bricks possess better reliability and workability in both the physical and thermal properties of clay bricks.