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The ever increasing environmental challenge arising from improper waste management has been a great concern to researchers and the society. One of such industrial waste is micro silica; a bye-product of the Carbothermic reduction of high purity quartz at temperature of about 2000oC in the presence of coke. The finess of this material and its pozollanic nature makes it suitable for use in the production of self-compacting concrete. In this research micro silica was introduced in percentages of, 5, 10 and 15% as partial replacement of cement in the production of self-compacting concrete. The fresh properties were examined using slump flow, T50cm, slump flow, V-funnel and blockage ratio using L-Box. As the Micro silica were introduced, T50cm time increased, Slump flow reduced, V-funnel flow time increased and L-Box value reduced, due to increase in viscosity. Comparing the experimental results with European Federation of National Associations of Representing for Concrete EFNARC 2002, blockage ratio for 15% was below 0.8. The compressive stresses at 28days were higher than the control at 28days compressive stress with 8.6%, 19.04% and 11.9% for 5%, 10% and 15% respectively. Thus, cement can be partially substituted with micro silica up to 15% with improvement in compressive strength in self-compacting concrete.

This experimental work evaluates the relationship between compressive strength and modulus of Elasticity of self-consolidating High performance concrete (SCHPC) containing high volume of Groundnut Shell Ash (GSA) up to 40% substitution as SCM. A total of 210 specimens of the GSA blended SCHPCs comprising 105 cubes (100 x100 mm) and 105 cylinders (150x300 mm) were cured in water for 7,14,28 ,56, 92,120 and 180 days hydration periods and the compressive strength and Modulus of elasticity determined. The linear relationships were studied with regression analysis. The findings revealed that all the mixes met the Modulus of Elasticity values requirement of 18,000N/mm2 to 42,000N/mm2 and the compressive results show that three substitution levels of 0%, 10% and 20% attained the proposed design strength (40-130 Mpa) and also satisfied the requirement for self-consolidating and high strength concretes. In conclusion, 0%-20% GSA substitutions (SCHPCA0-SCHPCA20) indicated a strong linear relationship with regressions values obtained varies between 0.842 and 0.954 for the two variables. Addition of GSA as SCM has improved the mechanical properties of SCHPC and creates a strong relationship between the compressive strength and Modulus of Elasticity.

The focus of this study is the prediction of Elasticity Modulus (ME) of Self-Consolidating high-performance concrete (SCHPC) incorporated with Groundnut Shell Ash (GSA) with Artificial Neural Networks (ANN). The present research utilized GSA as a SCM in the development of SCHPC with GSA (0, 10, 20, 30 and 40%) to produce concrete (SCHPC0, SCHPC10, SCHPC20, SCHPC30 and SCHPC40) and a designed concrete mix of 41 N/mm2 was employed in accordance with ACI and EFNARC guidelines. The compressive strength, tensile strength, Elasticity Modulus and microstructure densifications of SCHPC were the major parameters measured. The Elasticity Modulus was modelled with curing age, percentage substitution of GSA, tensile strength and compressive strength as input while output layer has only one neuron which represents modulus rupture as the target value, in this case, the Modulus Elasticity of GSA Blended SCHPC. Adequacy of adopted models was determined using coefficient of determination (R2) and Mean Square Error (MSE). phase transformation and microstructural analysis of SCHPC showed microstructure densification with an improved interface obtained from SCHPC10 and SCHPC20.The adopted model (back propagation 4-8-4-1) adequately predicted the EM properties of SCHPC (R2: 0.67–0.96; MSE: 0.28–4.81).

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