Pedro Montes

The effects of calcium nitrate based corrosion inhibitor (CNI) and fly ash on the corrosion of high performance concrete subjected to a simulated marine environment were investigated. Small-scale concrete slabs containing steel reinforcement were cast with a cover depth of 20 mm and with a construction joint intersecting the steel reinforcing at right angles. The slabs were subjected to a simulated marine environment with two cycles of wetting and drying per day. Corrosion activity of the reinforcing bars was evaluated using the linear polarization resistance technique and free water-soluable chloride content at the rear level was determined at the end of the testing period. Testing in areas away from the construction joint and away from corrosion induced cracking revealed that the water to cementitious materials ratio (w/cm) has a significant effect on the ingress of chlorides. Thus, chlorides content obtained for 0.29 and 0.37 w/c were less than one third that of 0.45 w/c concrete...

As a consequence of climate change that our planet is currently suffering, buildings are exposed to severe environmental conditions that tend to accelerate the deterioration of the materials that compose them. This effect provokes their sub-utilization in unsafe conditions or generates overspending by requiring continuous repairs in order to extend their service life. In the present paper, the progress of an extensive research project developed to evaluate various strategies to enhance the durability of reinforced concrete exposed to a marine environemnet is reported. Such strategies include the use of corrosion inhibitors, alone or in combination with supplementary cementitious materials in concrete structures, epoxy coated rebars and the use of a surface pre-treatment with a hydrophobic agent. To evaluate the effectiveness of the aforementioned strategies, accelerated laboratory testing and field testing were conducted. So far the results have shown to be promising, although to va...

This paper presents initial results from an extensive study of the effect of calcium nitrite-based corrosion inhibitor (CNI) and fly ash on the properties of high-performance concrete (HPC). A 33 full factorial design was developed to evaluate the influence of water-cement ratio ...