咸淡水交汇区混凝土结构耐久性研究  

Durability of Concrete Structures in Salt and Freshwater Confluence Area

作　　者：李毅 唐博文 李卫 丁平祥 范志宏[2,3,4] LI Yi;TANG Bowen;LI Wei;DING Pingxiang;FAN Zhihong(Bay Area Bridge Maintenance Technology Center,Guangdong Province Highway Construction Co.,Ltd.,Guangzhou 510230,China;CCCC Fourth Harbor Engineering Institute Co.,Ltd.,Guangzhou 510230,China;Key Laboratory of Construction Materials,CCCC,Guangzhou 510230,China;Key Laboratory of Harbor&Marine Structure Durability Technology,Ministry of Transport,Guangzhou 510230,China)

机构地区：[1]广东省公路建设有限公司湾区特大桥养护技术中心,广州510230 [2]中交四航工程研究院有限公司,广州510230 [3]中交集团建筑材料重点实验室,广州510230 [4]水工构造物耐久性技术交通运输行业重点实验室,广州510230

出　　处：《硅酸盐通报》2024年第12期4389-4397,共9页Bulletin of the Chinese Ceramic Society

基　　金：国家重点研发计划(2022YFB2603000)。

摘　　要：咸淡水交汇区域腐蚀介质的变化规律不明确且浓度较低,混凝土结构遭受的侵蚀方式变化较大,使用普通海洋环境下所建立的氯离子扩散模型来预测咸淡水交汇区域的混凝土结构寿命偏差较大。此外,咸淡水交汇区域混凝土结构的劣化规律也不同于海洋环境,照搬海洋环境下的防护措施对其进行耐久性维护会造成极大的资源浪费。针对此问题,本文依托南沙大桥工程,采用现场试验、室内试验和理论分析的方法对咸淡水交汇环境下混凝土结构的耐久性开展了研究。首先,对南沙大桥不同腐蚀环境下混凝土结构的碳化以及氯离子侵蚀情况进行了分析。其次,利用压汞法(MIP)、热重(TG)分析以及扫描电子显微镜(SEM)等微观表征手段对混凝土结构的孔隙分布、化学组分和微观结构进行了测定。本文可为咸淡水交汇区混凝土结构的寿命预测和维修加固提供参考。The alteration of corrosion mediums in the salt and freshwater confluence area is poorly understood,with low concentrations complicating matters further.This significantly changes the corrosion patterns of concrete structures,rendering the chloride diffusion models developed for marine environments inaccurate for predicting the lifespan of concrete structures in such salt and freshwater confluence areas.Additionally,the deterioration mechanisms in the salt and freshwater confluence area differ from those in marine environments.Hence,applying marine protective measures to these areas would lead to substantial resource wastage.To address this issue,this study leveraged the Nansha Bridge project,employing field tests,laboratory tests,and theoretical analyses to investigate the durability of concrete structures in the salt and freshwater confluence area.First,the carbonation and chloride corrosion of the concrete structure under different corrosion environments at Nansha Bridge were analyzed.Subsequently,the pore distribution,chemical composition,and microstructure of the concrete were characterized by mercury intrusion porosimetry(MIP),thermogravimetric(TG)analysis,and scanning electron microscopy(SEM).This study may have potential for the life prediction,repair,and reinforcement of concrete structures in the salt and freshwater confluence area.

关 键 词：混凝土 咸淡水交汇区 海洋环境 腐蚀环境 耐久性 微观性能 

分 类 号：TU528.31[建筑科学—建筑技术科学]