Cementitious materials have been widely used in the building and construction industry for centuries owing to their excellent mechanical and structural properties. Unfortunately, their durability, especially in windy and sandy environments, is highly susceptible to wind-blown sand erosion. Therefore, a thorough understanding of their sand erosion wear is of extreme importance in enhancing their durability and overall performance. To date, different models have been proposed to study and predict the erosion behaviors of cementitious materials, which are largely affected by the target material characteristics and test conditions. Promoting composite microstructures by decreasing the micro-cracks and micro-pores have been proposed as a promising method for enhancing the erosion resistance of these materials. Similarly, mineral admixtures like silica fumes have been successfully utilized to improve concrete microstructures, which has a significant impact on their erosion resistance properties.
Nevertheless, despite the extensive research work and good progress, more and more research is necessary to develop more effective methods for improving the erosion resistance of cementitious materials. Replacing fine aggregates with admixture minerals has exhibited great potential for improving corrosion resistance due to their ability to decrease micro-cracks and micro-pores. Moreover, advanced functional materials such as nanomaterials and graphene have been used as an additional admixture to promote the erosion resistance property of concrete. Interestingly, they too require the same mechanisms used in most existing studies.
Inspired by the previous findings, Professor Shi Yong and Professor Shi Zhiming. from the Inner Mongolia University of Technology developed an ultrasound surface treatment-based method for promoting the surface microstructure and improving the hardness property of cementitious materials. Their main aim was to investigate the effects of the ultrasonic hardening layer (UHL) on enhancing the wind-blown and erosion resistance performance of cementitious materials. Their research work is currently published in the journal, Wear.
In their approach, the proposed method comprised ultrasonic vibrators responsible for producing high-frequency vibrations on the material surfaces during the early hydration stage. Since particle erosion is common on material surfaces, the formation mechanism of the UHL was analyzed. Also, the density and surface hardness were measured during the tests. Finally, the feasibility of the proposed method in improving the erosion resistance of cementitious materials was experimentally validated.
Results demonstrated that the vibrations produced by the ultrasound on the material surface resulted in the formation of a hardening layer that further led to the improvement of surface hardness. After 28 days of curing, the resultant UHL exhibited a higher density and surface hardness that were 3.3% and 136%, respectively, higher than those of the contrast specimen. Similarly, the UHL, for specimens cured for 28 days, could potentially improve the erosion resistance up to 12.8 – 24.1%. The promotion of microstructure of the composite in the UHL was attributed to tight bonding between the UHL aggregates and the materials resulting in fewer interference defects.
In summary, the Professor Shi Yong and Professor Shi Zhiming study reported a feasible method for improving the wind-blown sand erosion resistance of cementitious materials based on ultrasound surface treatment. Unlike the contrast specimens, ultrasonic hardening layer exhibited higher surface hardness and density characteristics, which promoted the composite microstructure and erosion resistance of cementitious materials. The underlying mechanism of UHL for improving the erosion resistance of the material depended on the hardness of the UHL and the promotion of the microstructure. In a statement to Advances in Engineering, the authors will significantly contribute to future improvement of the anti-wind erosion resistance of cementitious materials.
Shi, Y., & Shi, Z. (2020). Ultrasonic surface treatment for improving wind-blown sand erosion resistance of cementitious materials. Wear, 460-461, 203185.