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This work reports on an investigation into the use of cowdung ash(CDA) as Supplementary Cementitious Material(SCMs) in concrete . Cement was replaced with cowdung ash (CDA) up to 30% at 5% interval. Setting times (initial and Final) and slump test were carried out on the fresh cement/CDA blended paste and concrete respectively. A total of 105mm cubes of 150mm dimensions were cast and cured in water for 7,14,28,60 and 90days and tested for compressive strength. The result of setting times indicates that as the percentage of CDA increases, the initial and final setting times increased by 12.2%-59.3% and 2.74%-43.90% respectively indicating the potential of Cowdung ash as a set retarder. The workability of concrete decreased as the cowdung ash content increases. The results on compressive strength showed a decrease with increasing cowdung ash content and an increase with curing age. There was no significant difference in compressive strength between the control concrete and those containing up to 15% Cowdung ash at 5% level of significance. A regression model showing the relationship between compressive strength, curing age and cowdung ash content was proposed which was highly significant and revealed that curing age and cowdung ash are useful predictor. eveloping countries like; Nigeria, Sudan, Republic of Be- nin, Asia-Pacific region e.t.c, are seeking to improve their inadequate infrastructure, they are faced with many challenges which include high cost of cement, diminishing national income due to the global economic recession, rising debt profile, decreas- ing foreign aid, scarcity of building materials-Cement, etc. In order to improve their infrastructure, cement (binder) and related materials are needed. Cement is the main binder in the produc- tion of concrete.The production of strong and durable concrete is fundamental to building better roads, bridges, houses, and civil infrastructure. The rising cost of cement particularly in the devel- oping countries has made it difficult for majority of the populace whom are low income earners to own houses. For instance, A 50 kg bag of cement, had, at a time, been sold for $17(N2500) in Ni- geria, while it settles for around $12.5(N2000) now. In the Repub- lic of Benin and Ghana, the same quantity sells for about $10(4500CFA) and $10.63(GH¢25.00) respectively as compared to 6$(N800.00) international price. Meanwhile, despite the huge increase in supply, the price of cement locally remains at least N2,000 per 50 kg bag, almost twice the international price of the same size of cement(1)-(4) . It can be duly noted that the exorbi- tant cost of cement production, government policies, among oth- er factors has made housing developers |
