Many parameters are influenced by the diffusion of chloride on concrete in marine environments and these can affect concrete quality. In this study, the effect of water to cement ratio of 0.35, 0.40 and 0.45 on corrosion resistance and compressive strength of reinforced concrete was evaluated. Moreover, different percentages of micro silica (SiO2) including 5, 7.5 and 10% were utilized, in order to investigate the effect of pozzolanic materials on the corrosion of steel in concrete. Then cubic samples reinforced with steel bar spacing of 2.5, 5 and 7 cm from the cube surface were made and put in Caspian sea water for 5 months. During this period, corrosion potential of steel was measured by a calomel half cell (SCE). In order to finalize the evaluation of the mechanical strength of the samples, concrete pressure test was conducted and the result showed that after 40, 44 and 59 days for the bars with depth of 2.5, 5 and 7 cm, respectively and the samples prepared with water-cement ratio of 0.35, the corrosion potential was -350V versus SCE, while the compressive strength was approximately 450 kg/cm2. This result showed longer life span of this sample in comparison with other water-cement ratios. By adding micro silica to the samples up to 7.5%, the time for obtaining a corrosion potential of -350V, bars with depth of 2.5, 5 and 7 cm, was 43, 50 and 86 days, respectively, and the compressive strength of this sample was approximately 480 kg/cm2. Consequently, it is arguable that in order to achieve longer life span of corrosion and suitable compressive strength, the optimum ratio of water to cement should be 0.35 and the percentage of pozzolan SiO2 should be 7.5%.
AUTHOR KEYWORDS: Chloride; Corrosion Potential; Micro silica; Steel Corrosion INDEX KEYWORDS: Cements; Chlorine compounds; Concretes; Corrosion; Corrosion resistance; Pozzolan; Reinforced concrete; Seawater; Silica; Silicon compounds; Steel corrosion; Strength of materials, Chloride; Concrete quality; Corrosion of steel in concretes; Corrosion potentials; Effect of water; Marine environment; Pozzolanic materials; Water-cement ratio, Compressive strength PUBLISHER: Materials and Energy Research Center
AUTHOR KEYWORDS: Ant colony algorithm; Sampling design space; Structural optimization INDEX KEYWORDS: Ant colony optimization; Artificial intelligence; Set theory; Shape optimization; Structural optimization, Ant colony algorithms; Design variables; Improved ant colony algorithm; Related variables; Sampling design; Skeletal structures; Speed of convergence; Standard optimization, Optimization, algorithm; design method; optimization; public space; sampling PUBLISHER: Budapest University of Technology and Economics
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