Preparation and characterization of cement mortar mixed with alternating field-magnetized water

With the rapid development of industrialization, it is essential to use high-performance building materials and environmentally safe construction methods. Although earlier studies have shown that magnetized water has a significant strengthening effect on cement materials, they have rarely used alternating magnetic fields. This study explores the preparation conditions of magnetized water under alternating magnetic fields, aiming to obtain the optimal strengthening effect on cement mortar. The variation in surface tension of magnetized water is analyzed. The prepared magnetized water and Portland cement are used to mix mortar with water-to-cement ratios (w/c) of 0.74, and the apparent density, compressive strength, and microscopic appearance (under scanning electron microscope) of the mortar are observed. The results show that the surface tension of magnetized water decreases as the frequency of the alternating magnetic field increases, thereby improving the apparent density and compressive strength of the mortar. A relevant mathematical model is proposed. When the frequency of the alternating magnetic field is higher than 800 Hz, the surface tension of magnetized water significantly decreases, with a maximum reduction of 20.6%; The compressive strength of magnetized water mortar has significantly increased, with a maximum increase of 14.8%. Under appropriate magnetic field parameters, strength requirements can be met with a reduction of 10% in the consumption of cement and water. By exploring the optimal magnetic treatment conditions for alternating magnetic fields, this study provides a theoretical basis for the design of magnetizers in engineering applications.