Kaiyin Zhao , Hengrui Liu , Lucen Hao , Shuangshuang Liu , Shipeng Zhang , Chi Sun Poon
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引用次数: 0
Abstract
The study aimed to elucidate the mechanism behind rheological modification due to CO2 mixing at the mixing and post-mixing stages from an electrochemical perspective. The results indicated that CO2 mixing reduced the flowability while increasing penetration resistance and static yield stress. The electrostatic attraction between particles with opposite surface charges and the bridging effect of calcium carbonate constitute the primary factors for influencing the rheological properties of mortar at an early age. The altered surface charge of carbonized cement particles, primarily resulting from CO2 injection lowering the pH and ion concentration, reversed the zeta potential of particles from the traditionally negative charge (−3.59 mV) to a positive value (+13.3 mV). Furthermore, CO2 mixing further enhanced the dissolution of cement particles and accelerated the hydration process, thereby increasing the rate of structural build-up. CO2 mixing was demonstrated to be a potential rheological modifier for 3D-printed concrete applications.
期刊介绍:
Cement & concrete composites focuses on advancements in cement-concrete composite technology and the production, use, and performance of cement-based construction materials. It covers a wide range of materials, including fiber-reinforced composites, polymer composites, ferrocement, and those incorporating special aggregates or waste materials. Major themes include microstructure, material properties, testing, durability, mechanics, modeling, design, fabrication, and practical applications. The journal welcomes papers on structural behavior, field studies, repair and maintenance, serviceability, and sustainability. It aims to enhance understanding, provide a platform for unconventional materials, promote low-cost energy-saving materials, and bridge the gap between materials science, engineering, and construction. Special issues on emerging topics are also published to encourage collaboration between materials scientists, engineers, designers, and fabricators.