JETI Admin2
Abstract
Proper curing of concrete structural elements is essential for hydration reaction to continue and to develop concrete compressive strength over time. Hydration of concrete and strength development will continue for years, but at decreasing rate, if water is available to cement within concrete structural element and temperature is reasonable. For most building codes, concrete structural components and systems are designed for the 28-day compressive strength. Nonetheless, concrete structures are cured typically for only 3 to 7 days. There is an increasing use of curing techniques that involve chemical compounds such as acrylic-based compounds. The emergence of such techniques requires investigation of their effectiveness, compared to traditional curing methods. This research is aimed at comparing the compressive strength of concrete cured using three methods namely submersion in water, wet sack and exposed to air method. Water cement ratio of 0.6 was used and a mix ratio of 1:2:4 on all the concrete cubes and the compressive strength of each sample was determined on standard 150 mm x 150 mm x 150 mm cubes made of self-consolidated concrete (SCC). Nine cubes were crushed for each curing age (days) of 7, 14, 21 and 28 days respectively, and their compressive strength was determined. The compressive strength of each curing method are as follows; curing by immersion in water method are 24.5N/mm2, 25.93N/mm2, 28.37N/mm2 and 30.74N/mm2. Then Hessians’ (wet sack) curing method are 10.37N/mm2, 12.22N/mm2, 12.82N/mm2 and 13.93N/mm2 while Air curing at room temperature are 5.26N/mm2, 6.29N/mm2, 7.48N/mm2 and 8.15N/mm2. The curing age last for 7, 14, 21 and 28 days respectively. The compressive strength of each curing method was recorded in their respective affiliated tables and the values obtained are used to plot a graph with the compressive crushing strength at Y-axis and the curing ages (days) at X-axis. Also, Bar Chart of each curing method was plotted with the compressive crushing strength at Y-axis and the curing method at the X- axis for all the methods to ascertain from the bar chart which method is more effective. Generally, from the experiments of this research, immersion in water method has proven to produce the highest 28-day compressive strength compared to other curing methods, and air curing method is the least effective method.
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