Air Cooling

Fire exposure destroys concrete structures, and the cooling methods significantly impacts residual strength Rapid cooling, especially with water, may cause additional damage due to thermal shock, yet limited studies compare air- and water- cooling effects. In order to determine which cooling technique best maintains structural integrity, this study will examine how various techniques affect the breaking strength of Grade 30 concrete exposed to temperatures of 200°C, 400°C, and 600°C. This study involves the preparation of Grade 10 concrete specimens, which were cured for 28 days before being subjected to elevated temperatures of 2000C 400C and 600°C in a controlled furnace. After exposure, the specimens were cooled using air and water to compare the effects of each method on compressive strength. The compressive strength of all samples was tested using a compression testing machine, and the results were analyzed through tabular and graphical comparisons to evaluate strength reduction trends. The study revealed that compressive strength decreased with increasing temperature, with watercooled samples experiencing greater strength loss than air-cooled due to rapid thermal shock. At 600°C, Average water-cooled samples record 26.561 N/mm², while air-cooled samples record 28.014 N/mm², confirming that gradual cooling helps to retain more structural integrity. Based on these findings, air cooling is recommended as a safer and more effective method for post- fire concrete recovery. Further research should explore advanced cooling techniques to enhance fire resistance and durability.