INVESTIGATION ON STRENGTH CHARACTERISTICS OF PERVIOUS CONCRETE PRODUCED WITH COARSE AGGREGATE SIZES

Abstract

Pervious Concrete is a unique kind of concrete with high porosity that reduces the water runoff from particular site. This study evaluated the effect of coarse aggregate sizes on the properties of pervious concrete. Granite was collected on an ongoing construction site at Ajayi Crowther University, Atiba Local Government Area, Oyo State. Production of pervious concrete was carried out by using aggregate sizes with the mixing ratio 1:4 and water cement ratio 0.55 which later increased to 0.65. Slump and compacting factor test were carried out to check the effect of coarse aggregate sizes on the workability of fresh concrete. A total of Twenty Seven (27) cubes of size 150 x 150 x 150 mm³ were cast. The pervious concrete were tested for compressive strength, density, water absorption, permeability, abrasion resistance and void contents at the ages 14, 21 and 28 days. The slump value increased from 85 mm for 12.7 mm granite to 105 mm with 25.40 mm of granite, as the size of aggregate increased indicating that pervious concrete becomes less workable as the aggregate size increased while the compacting factor value varied from (0.975-0.995). The compressive strength of pervious concrete at 28 days ranges from 14.95 - 16.25 N/mm2, Bulk density ranges from 1725 to 1830.05 Kg/m³, water absorption ranges from 2.29-1.01%, void content ranges from 18.20-23.25%, permeability ranges from 8.50-12.15 mm/s, and Abrasion resistance range 0.21-1.90 Kg. It was observed that only coarse aggregate size shows high degree of water permeable. Pervious concrete exhibit better porosity properties than ordinary Portland cement concrete, pervious concrete is therefore recommended for the construction of farm structure for irrigation purposes.

KEYWORDS: Concretes, Aggregates, Granites, Cement, Compressive strength