Experimental Investigation on the Durability Properties of Concrete under Aggressive Environmental Conditions

Concrete structures exposed to aggressive environmental conditions often experience premature deterioration, resulting in reduced service life and increased maintenance costs. This study investigates the mechanical and durability performance of M15 grade concrete subjected to varying curing durations and hostile exposure conditions. Standardized laboratory tests were conducted to evaluate compressive strength, split tensile strength, water absorption, sulfate resistance, carbonation depth, and fire resistance. The influence of extended curing on both strength development and durability characteristics was systematically analyzed. The results demonstrate that prolonged curing significantly enhances the overall performance of concrete. Water absorption decreased from 6.45 to 5.65%, representing a 12.4% reduction, indicating improved pore structure refinement and reduced permeability. Sulfate resistance showed noticeable improvement, with mass loss restricted to 8.05%, confirming enhanced resistance to chemical attack. Carbonation depth was reduced by 16.2%, further validating the concrete’s ability to withstand long-term environmental degradation. Mechanical properties also exhibited substantial improvement with extended curing. Compressive strength increased from 18.5 to 25.8 MPa, reflecting a 39.4% gain, while split tensile strength improved from 2.05to 2.65 MPa, an increase of 29.3%, indicating better crack resistance and structural integrity. Fire resistance testing revealed minimal strength loss of only 6.5% after one hour of exposure at 400°C, demonstrating satisfactory thermal stability under elevated temperatures. Overall, the developed M15 concrete mix exhibits a balanced synergy between strength and durability. The findings suggest that with appropriate curing practices, conventional concrete can perform effectively in coastal, industrial, and high-temperature environments, supporting sustainable construction practices and extended service life.