水下不分散混凝土抗分散剂优化设计与凝结时间调控

刘祥胜 $ ^{1} $，纪厚祥 $ ^{1} $，郑圣飚 $ ^{2} $，詹炳根 $ ^{2,3,4} $，余其俊 $ ^{2,3,4} $，李占甫 $ ^{5} $

(1. 安徽省交通控股集团有限公司, 安徽合肥 230088; 2. 合肥工业大学土木与水利工程学院, 安徽合肥 230009; 3. 水泥基材料低碳技术与装备教育部工程研究中心, 安徽合肥 230009; 4. 安徽省水泥基材料低碳技术工程研究中心, 安徽合肥 230009; 5. 中交二航局第四工程有限公司, 安徽芜湖 241000)

摘要

水下不分散混凝土(non-dispersible underwater concrete, NDC)为涉水工程的施工提供抗冲刷能力,为实现水下不分散混凝土性能的提升,文章探讨抗分散剂的优化设计和凝结时间的调控,选取聚丙烯酰胺(polyacrylamide, PAM)和羟丙基甲基纤维素(hydroxypropyl methyl cellulose, HPMC)作为抗分散剂主剂,聚羧酸减水剂、有机硅和聚醚类消泡剂作为辅料,从抗分散性和流动性的角度对水下不分散混凝土抗分散剂的组成进行优化设计,同时选取碳酸锂和硫酸铝作为调凝剂,对水下不分散混凝土的凝剂时间进行调控。研究结果表明:采用HPMC作为主剂、聚羧酸减水剂和聚醚类消泡剂作为辅剂制备抗分散剂,可以使得水下不分散混凝土具有较好的抗分散性和流动性;其中,含水泥质量分数0.45%的HPMC和1%聚羧酸减水剂的新拌水泥砂浆(水胶质量比为0.5,胶砂质量比为2)表现出优异的抗分散性和良好的流动性,其pH值为9,扩展度为150 mm;在该体系中,硫酸铝的调凝效果较好且经济效益更高,但使用时用量应少于2%。对抗分散剂的优化设计和凝结时间的调控为水下不分散混凝土的相关实验研究提供了重要参考。

关键词

水下不分散混凝土（NDC）；抗分散剂；减水剂；凝结时间

中图分类号：TU528

文献标志码：A

文章编号：1003-5060（2024）10-1427-07

Optimization design of anti-dispersant and setting time regulation for non-dispersible underwater concrete

LIU Xiangsheng $ ^{1} $, JI Houxiang $ ^{1} $, ZHENG Shengbiao $ ^{2} $, ZHAN Binggen $ ^{2,3,4} $, YU Qijun $ ^{2,3,4} $, LI Zhanfu $ ^{5} $

(1. Anhui Transportation Holding Group Co., Ltd., Hefei 230088, China; 2. School of Civil and Hydraulic Engineering, Hefei University of Technology, Hefei 230009, China; 3. Engineering Research Center of Low-carbon Technology and Equipment for Cement-based Materials of Ministry of Education, Hefei 230009, China; 4. Anhui Province Engineering Research Center of Low-carbon Technology for Cement-based Materials, Hefei 230009, China; 5. CCCCSHEC Fourth Engineering Co., Ltd., Wuhu 241000, China)

Abstract

Non-dispersible underwater concrete (NDC) provides erosion resistance for the construction of wading projects. In order to improve the performance of NDC, the optimization design of anti-dispersant and the regulation of setting time were investigated. Polyacrylamide (PAM) and hydroxypropyl methyl cellulose (HPMC) were selected as the main anti-dispersants, and polycarboxylic acid water-reducing agent, silicone and polyether defoamer were selected as the auxiliary agents to optimize the design of NDC anti-dispersant from the perspective of anti-dispersion and flowability. Lithium carbonate and aluminum sulfate were selected as setting agents to regulate the setting time of NDC. The results show that the NDC anti-dispersant, which was prepared with HPMC as the main agent, polycarboxylic acid water-reducing agent and polyether defoamer as auxiliary agents, displays superior anti-dispersant performance.

Keywords

non-dispersible underwater concrete(NDC); anti-dispersant; water-reducing agent; setting time

收稿日期：2023-01-17

修回日期：2023-03-17

基金项目：国家自然科学基金资助项目（51972115）；合肥工业大学产学研校企合作资助项目（W2020JSKF0615）