Enhancing Compressive Strength of Sulfate-Rich Concrete Using Electromagnetic Fields

Abstract

Concrete deterioration due to sulfate attack is one of the factors for early failure. Considering that sulfates in aggregates are the most important problem related to concrete in the cities of the Middle East and especially Iraq, so there was a need to develop a device to enhance the strength of concrete. In the current experimental research, we sought to discover how to treat and improve the performance of fresh concrete containing high percentages of sulfate salts in sand, using a magnetic field generation device with an electrical principle made locally. The work included the beginning of casting 27 models of concrete cubes that were treated using different magnetic intensities and examined to select the highest strength, which was 3000 Gauss, which was adopted in this research. Two groups of mixtures were prepared and poured using 72 cubes and prisms. The first group was divided into two reference mixtures not treated with a magnetic field. Two types of sand with different sulfate ratios with resistant Portland cement were used. The second group was prepared using the same method and working conditions, except for treating the concrete mixture with electromagnetic fields. The results showed an encouraging improvement in the compressive strength of magnetically treated concrete, where the rates of increase in compressive strength were (5.45, 5.5, 5.7%) with 0.15% SO3, and (7.2.7, 4.6%) with 0.6%. SO3 for a period of (7.28 and 90) days, respectively, compared to control mixtures. This technology can be applied during the pouring process on job sites.