Ren Zhenhua, Guo Jia, Chen Wei, Zeng Xiantao, Wang Xiang Yu
Hunan Provincial Key Laboratory of Intelligent Disaster Prevention-Mitigation and Ecological Restoration in Civil Engineering, Hunan Institute of Engineering, Xiangtan, 411104, China.
School of Civil Engineering and Architecture, East China Jiao Tong University, Nanchang, 330013, China.
Sci Rep. 2024 Aug 19;14(1):19212. doi: 10.1038/s41598-024-69671-2.
The application environment for concrete is becoming increasingly complex, accompanied by an intensification of its functional requirements. This paper presents a method for developing self-compacting concrete with conductive properties using limonite and graphite as the concrete conductive phases. In the process of concrete preparation, the limonite is initially treated by a pre-wetting method to prevent the surface depression caused by the addition of limonite during the concrete curing process. The second stage of the process involved optimising different proportions of limonite and graphite and different dosages of water-reducing agent, defoamer and dispersant to prepare concrete. The influence of different dosages of limonite and graphite and different dosages of water-reducing agent on the mechanics and electrical conductivity of concrete was studied in order to obtain self-compacting conductive concrete with performance indicators meeting the requirements of self-compacting and electrical conductivity. The results demonstrate that the mechanical and electrical properties of self-compacting conductive concrete prepared with polycarboxylic acid superplasticizer and retarding superplasticizer combined with superplasticizer are satisfactory, and the composite superplasticizer can function in conjunction with dispersant. The self-compaction index, slump expansion, expansion time T50 and J-ring expansion of fluid concrete meet the requisite standards. Once the concrete has reached the designated curing age, its compressive strength and flexural strength align with the anticipated design expectations, while its resistivity meets the stipulated conductivity index requirements.
混凝土的应用环境日益复杂,其功能要求也不断提高。本文提出了一种以褐铁矿和石墨作为混凝土导电相来制备具有导电性能的自密实混凝土的方法。在混凝土制备过程中,首先采用预湿法对褐铁矿进行处理,以防止在混凝土养护过程中因添加褐铁矿而导致表面凹陷。该过程的第二阶段包括优化褐铁矿和石墨的不同比例以及减水剂、消泡剂和分散剂的不同用量来制备混凝土。研究了不同用量的褐铁矿和石墨以及不同用量的减水剂对混凝土力学性能和导电性的影响,以获得性能指标满足自密实和导电性要求的自密实导电混凝土。结果表明,采用聚羧酸高效减水剂、缓凝高效减水剂复配高效减水剂制备的自密实导电混凝土的力学性能和电学性能良好,复合高效减水剂可与分散剂协同作用。大流动性混凝土的自密实指标、坍落度扩展度、扩展时间T50和J环扩展度均符合规定标准。混凝土达到规定养护龄期后,其抗压强度和抗折强度符合预期设计要求,其电阻率满足规定的导电率指标要求。