Effect of static magnetic field treatment on fresh concrete and water reduction potential

Abstract

The current research proposes to conduct experimental studies to examine the optimal method of magnetic treatment for the mixes and provides guidelines to use in the concrete mix design. Six magnetic flux densities (25, 50, 100, 200, 400 and 500 millitesla) were considered. More than 180 specimens were considered in the experimental program. In each experiment the fresh mix was divided into two portions; the first portion was untreated, while the other portion passed through a magnetic field. The mechanical properties named workability, compressive strength, spitting tensile strength, flexural and bond slip behavior were examined. Experimental results clearly demonstrated noticeable increases in the compressive strength of the concrete mixes up to 16 %. The workability was increased by about 7 %–26 % and the maximum increases in workability were recorded for 400 m T flux density treatment. Splitting tensile strength, flexural and bond slip strength were also enhanced when the magnetic treatment is carried out for the fresh mixes, also all treated specimens showed significant ductile behavior. The current study showed that the water reduction potential can be utilized and recommended with maintaining similar workability when the magnetic treatment is conducted for mixes. The characteristic of resulted concrete improved in terms of compressive and tensile strength in about 29 % and 27 % respectively. However, with these advantages, the current study can be considered as first step towards production of fresh treated mixes and this might give engineers more confidence to use magnetic field treatments to the concrete mixes during production and placing process.