Kesheng Yin , Peiliang Shen , Limin Zhang , Yamei Cai , Dongxing Xuan , Chi Sun Poon
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引用次数: 0
Abstract
Seawater cement slurry (SCS) is a commonly used binder in offshore deep cement mixing (DCM) construction. Seawater cement slurries are usually prepared before they are grouted into the seabed and mixed with marine clay. The aim of this study is to explore the feasibility of applying carbonation technology to fabricate SCS suitable for offshore DCM while achieving carbon sequestration and obtaining better mechanical properties for stabilised marine sediments.
This study demonstrated that after appropriate carbonation, carbonized SCS can be used in DCM to replace conventional SCS. Short-term carbonation promotes cement dissolution and hydration rates under seawater conditions rich in magnesium, calcium, and other inorganic ions. The carbonates include calcite, vaterite and amorphous carbonates, which provide additional nucleation sites for the hydration of SCS, resulting in an increment for amorphous CS(A)H gel with a dense pore structure and binding interaction with soil particles. After carbonation with 20 % CO2 for 5 min (0.5 wt% of cement), the UCS and secant modulus of cement-soil mixtures by 15.7 % and 111 % at the age of 1 day, and by 6.82 % and 10 % at the age of 28 days when treating marine clay with 80 % moisture content at a dosage of 260 kg/m3.
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.