摘要
针对西村港跨海大桥服役的海洋环境条件,以跨海大桥处于浪溅区的墩柱部位混凝土为研究对象,在C45海工混凝土常规配合比的基础上,通过优化设计掺合料配方,制备出一系列高性能海工混凝土;研究了掺合料对海工混凝土的微观结构、力学性能和耐久性影响。试验结果表明,通过引入偏高岭土、微珠等高性能掺合料组分后,随着掺合料增加,混凝土的孔径大小及孔隙率均有明显下降,致密性得到显著提高;28d抗压强度略有提升;电通量大幅度下降。与C45混凝土基础配方制得的混凝土相比,当掺合料质量百分比为19%时,其抗压强度高达60MPa,而电通量低至77.8C,降低了86.49%,大大提高了抗氯离子渗透性能;分析高性能海工混凝土耐久性能提升的机理在于高性能矿物掺合料的合理选择与颗粒级配优化,矿物掺合料的火山灰效应和形态效应的影响。
In view of the marine environmental conditions of Xicun Port Cross-sea Bridge, the concrete at the pier column of the cross-sea bridge in the splash zone is the research object. On the basis of the conventional mix proportion of C45 marine concrete, a series of high-performance marine concrete is prepared by optimizing the admixture formula. The influence of admixtures on the microstructure, mechanical properties and durability of marine concrete is studied. The test results show that after the introduction of high-performance admixture components such as metakaolin and microbeads, the pore size and porosity of the concrete are significantly reduced with the increase of admixtures, and the compactness is improved. Its 28 d compressive strength is slightly improved, and its electric flux is greatly reduced. Compared with the concrete made with C45 basic formula, when the admixture is 19%, its compressive strength is as high as 60 MPa, while the electric flux is as low as 77.8 C, which is reduced by 86.49%. The resistance to chloride ion penetration and durability of concrete are improved. The mechanism of improving the durability of high-performance marine concrete is lied in the reasonable selection of high-performance mineral admixtures, particle gradation optimization, and the influence of the pozzolanic effect and morphological effect of mineral admixtures.
作者
王宇
王睿
李冬云
郭张锋
李宏强
杨丰尚
葛洪良
WANG Yu;WANG Rui;LI Dongyun;GUO Zhangfeng;LI Hongqiang;YANG Fengshang;GE Hongliang(China Jiliang University,Hangzhou,Zhejiang 310018,China;The Third Engineering Co.,Ltd.of China Railway 20th Bureau Group Co.,Ltd.,Chongqing 400065,China)
出处
《施工技术（中英文）》
CAS
2022年第6期14-18,共5页
Construction Technology
关键词
桥梁工程
混凝土
高性能海工混凝土
配合比
耐久性
矿物掺合料
bridges
concrete
high-performance marine concrete
mix proportion
durability
mineral admixtures
