水下不分散混凝土的性能研究综述

Research of Anti-Washout Underwater Concrete

摘要: 水下不分散混凝土的快速凝结是其应用于抢险救灾与防渗堵漏、水下结构物的快速修复与加固、特殊与苛刻环境下的水下施工等特殊工程领域的技术要求。然而，水下环境的复杂性，体现在水流冲刷和压力变化，这使得混凝土在早期凝结过程中的稳定性难以保障，进而对其抗分散性能与早期强度发展提出了极高要求。本文在系统梳理水下不分散混凝土快速凝结技术研究进展的基础上，通过流变试验研究了絮凝剂(UWB-Ⅱ型)与聚羧酸系减水剂对水泥浆体工作性能的影响规律。综述部分深入探讨了以速凝剂、抗分散剂、早强剂为核心的外加剂复配技术，研究了不同速凝剂(铝酸盐、硅酸盐、无机盐类)与各种水泥的适应性，并涵盖了胶凝材料优化(如硅灰、纳米二氧化硅等矿物掺合料)与工作性保障(如纤维素醚、絮凝剂等新型抗分散剂)等方面的研究进展，对比分析了不同技术方案的优劣、适用条件及其对混凝土最终力学性能与耐久性的影响。试验结果表明，絮凝剂掺量对浆体屈服应力呈现“低掺量抑制、高掺量增强”的双重作用，对幂律指数则呈非单调影响；减水剂可在一定范围内缓解工作性与抗分散性之间的矛盾。最后，在指出速凝与工作性难以兼顾、长期耐久性评估不足等现存挑战的基础上，本文对未来研究路径进行了展望，强调其重点应聚焦于：开发绿色复合型外加剂、应用智能材料以精准调控凝结行为，以及建立可靠的长期性能预测模型。本综述旨在为水下快速凝结混凝土的材料设计与工程应用提供理论参考。

Abstract: The rapid setting of non-dispersible underwater concrete is a technical requirement for its application in emergency rescue and disaster relief, seepage prevention and leakage control, rapid repair and reinforcement of underwater structures, and underwater construction in special and harsh environments. However, the complexity of the underwater environment, characterized by water flow scouring and pressure changes, makes it difficult to ensure the stability of concrete during the early setting process, thereby imposing extremely high demands on its anti-dispersion performance and early strength development. Based on a systematic review of the research progress on rapid setting technology of non-dispersible underwater concrete, this paper experimentally investigated the effects of flocculant (UWB-II type) and polycarboxylate superplasticizer on the workability of cement paste. In the review part, the admixture compounding technology centered on accelerators, anti-dispersants and early-strength agents was discussed in depth; the adaptability of different accelerators (aluminate, silicate and inorganic salt types) to various cements was studied; and the research progress in cementitious material optimization (mineral admixtures such as silica fume and nano-silica) and workability assurance (novel anti-dispersants such as cellulose ethers and flocculants) was summarized. The advantages and disadvantages of different technical solutions, their applicable conditions, and their effects on the final mechanical properties and durability of concrete were compared and analyzed. The experimental results show that the flocculant dosage exhibits a dual effect of “inhibition at low dosage and enhancement at high dosage” on the yield stress of paste and has a non-monotonic influence on the power-law index; the superplasticizer can alleviate the conflict between workability and anti-washout resistance to a certain extent. Finally, based on the existing challenges such as the difficulty in balancing rapid setting and workability and the insufficiency of long-term durability assessment, future research directions were prospected, emphasizing the development of green composite admixtures, the application of smart materials to precisely control the setting behavior, and the establishment of reliable long-term performance prediction models. This review aims to provide theoretical references for the material design and engineering application of underwater rapid-setting concrete.