ABSTRACT
The Reuse of waste glass in concrete production is among the attractive option of achieving waste reduction and preserving the natural resources from further depletion thereby protecting the environment and achieving sustainability. This present study examined the variation in the strength prope1ties of concrete using waste glass aggregate (WGA) as partial replacement for different coarse aggregates grading. 20mm and =(25mm coarse aggregates were partially replaced with WGA of respective sizes in different percentages of 0%, 10%, 20% and 30%. Physical properties such as specific gravity, bulk density, slump, and workability of fresh concrete and strength properties such as compressive strength and tensile strength of hardened concrete of grade M25, mix ratio 1: 1 :2 were tested after 7, 14, 28, 56 and 90 days. The results of the physical properties revealed that the WGA exhibited lower specific gravity value of 2. 70, bulk density of 1364kg/m 3, moisture content of 0% as compared to granite of specific gravity value of 2.74, bulk density 1660kg/rn3, and moisture content of 0.01 %. The compressive strength results of both 20mm and 25mm WGA increases as the curing age of the concrete increases progressively from 7days up to 90days. At 7 and 90 days the compressive strength results of 20mm aggregate of the control mix concrete were 30.05N/mm 2 and 42.60N/mm 2 respectively while that of 20mm 30% WGA paitial replacement were 32.14N/mm 2 and 45.70N/mm 2 respectively, and for 25mm aggregate control mix concrete were 29.74N/mm 2 and 49.80N/mm 2 respectively, while that of 25mm, 30% WGA partial replacement were 28.71N/mm 2 and 45.50 N/mm 2 respectively. The tensile strength for all the ages reached optimum value at 10% partial replacement WGA for both 20mm and 25mm. At 28days, the tensile strength result of 20mm aggregate of the control mix concrete was 2.86N/rnm2, while 20mm 10% WGA replacement was 2.90N/mm 2, and for 25mm aggregate control mix concrete, tensile strength result was 3.l 1N/mm 2 while that of 25mm WGA 2.55N/mm 2. The results of the strength properties showed that the concrete grade M25 adopted was suitable for the WGA partial replacement as the compressive strength results for all ages did not fall below 25N/mm 2.