Effect of Magnetic Field and Titanium Oxide Nanoparticle on the Mechanical Properties of Concrete

Abstract

This research explores the novel application of magnetic fields in conjunction with Titanium Oxide (TiO2) nanoparticles to enhance the mechanical properties of concrete, presenting a transformative approach in concrete technology. By investigating this innovative synergy, the study aims to reduce cement content—an unprecedented step towards minimizing the carbon footprint—while simultaneously improving concrete strength. The potential scientific contribution lies in pioneering a method that not only boosts performance but significantly lowers greenhouse gas emissions, offering a sustainable alternative to traditional concrete production techniques. The present experimental study investigates the influence of magnetic field intensity, exposure duration, and titanium dioxide (TiO2) nanoparticle fraction on the compressive strength and microstructural behavior of concrete with reduced cement content. Concrete mixes with a 10% reduction in cement content were prepared with TiO2 nanoparticle additions of 0.5%, 2%, and 4% by weight of cement. These mixes were subjected to a uniform magnetic field treatment at induced voltages of 25 V and 80 V, generating maximum magnetic flux densities of approximately 270 mT and 450 mT, respectively. The treatments were applied for 2 and 5 minutes, in both the fresh and hardened states of the concrete. Mechanical behavior was evaluated through compressive strength tests at 7 and 28 days, accompanied by scanning electron microscopy (SEM) analysis to assess microstructural changes. Results revealed that incorporating 4% TiO2 nanoparticles alone significantly compensated for the reduced cement content, achieving a compressive strength increase up to 17.7% at 7 days and 7.42% at 28 days compared to the control sample. Magnetic field application further improved mechanical properties, with maximum strength enhancements reaching approximately 32% at 7 days and 22% at 28 days for specimens treated at optimal conditions (25 V for 5 minutes). SEM analysis confirmed that applying magnetic fields improved nanoparticle dispersion, accelerated cement hydration, increased calcium silicate hydrate (C-S-H) gel density, and reduced porosity, leading to a denser and more cohesive microstructure. However, higher magnetic intensities (at 450 mt ) induced overheating, causing micro-cracking and limiting mechanical benefits. Fresh-state magnetic exposure yielded superior early-age strength gains at medium-to-high nanoparticle concentrations, while hardened-state exposure provided sustained long-term benefits at lower concentrations. The findings suggest a promising strategy for enhancing concrete properties through controlled magnetic field treatment and nanoparticle incorporation, potentially reducing cement content, and thus the carbon footprint, without compromising structural integrity—an area not comprehensively explored previously.