Application of Regression Model in Predicting Compressive Strength of Concrete Incorporating Aloe Vera Gel as Admixture

Abstract

This research examined the impact of aloe vera gel (AVG) as an admixture on the compressive strengths of concrete and to model these properties with Ibearugbulem’s Approach using Visual Basic program. Data used for the model were obtained experimentally. The fresh and hardened properties of AVG-concrete were determined at 7, 14, 21, and 28 curing days with a water-binder ratio of 0.6 and AVG content varying at 0.5% increasing dosage of cement weight up to 5%, using mix ratios of 1:1.5:3 and 1:3:5. Grain size analysis, specific gravity tests, workability tests, setting-time tests, compressive strength’ test were carried out. A total of two hundred and sixty-four 150 × 150 × 150 mm’ concrete cubes were made for compressive strength test. Ibearugbulem’s concept was adopted to develop a model for prediction and strength-optimization of AVG-cement concrete. For the quantity of the constituent ingredients, the response function is expressed as a multivariable function, with respect to the spatial-domain for individual concrete mix content. Response function was formulated within the distinguished spatial-domain and was optimized with the variational approach. The results reveal that mix ratio of 1:1.5:3 is more workable than those made with the ratio of 1:3:5 and slump values increased as the addition of AVG content increased from 0.5 to 5. For mix ratio of 1:1.5:3 and 1:3:5, the optimum experimental and model compressive strength was 31.42 N/mm2 and 33.23N/mm2, 31.78 N/mm2 and 34.83 N/mm2 respectively at 28 curing days and 2.0% AVG inclusion. At 0.60 water-cement ratio, it is recommended to use aloe vera gel not exceeding 2.0%. wt. of cement. The Student’s T-test statistical tool which was employed to evaluate the model performance at a 0.95 confidence status, affirmed that the model herein is reliable and apt for AVG-concrete.