Carbonation of concrete made with dredged marine sand and its effect on chloride binding

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal

20 Scopus Citations
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Author(s)

  • Wei Liu
  • Hongzhi Cui
  • Zhijun Dong
  • Feng Xing
  • Haochuang Zhang

Detail(s)

Original languageEnglish
Pages (from-to)1-9
Journal / PublicationConstruction and Building Materials
Volume120
Online published20 May 2016
Publication statusPublished - 1 Sep 2016

Abstract

River sand (RS) has been overly exploited to meet demand in the construction industry, particularly in China. Chloride salt in dredged marine sand (DMS) is the primary concern that limits the use of DMS in reinforced-concrete (RC) structures. This paper developed an interaction model between the carbonation behaviour and chloride ions in DMS concrete compared with RS concrete. In this research, the test results indicated that the chloride ions introduced by DMS can reduce 20-50% carbonation of the DMS concretes. A higher carbonation resistance can reduce the possibility of steel bar corrosion in the concrete. The process of concrete carbonation can alter the state of chloride ions in the concrete and their concentrations. During the carbonation process, the bound chloride ions would become free, and their concentration in carbonated concrete could increase by up to 200% compared to that of uncarbonated concrete when the chloride ion concentration was less than 3% by cement mass. Therefore, the effect of carbonation on chloride ions must be considered with respect to the durability when DMS concrete is designed for use in RC structures.

Research Area(s)

  • Dredged marine sand, Concrete, Carbonation, Chloride ions, Friedel's salt, C-S-H, ACCELERATED CARBONATION, PORTLAND-CEMENT, MECHANICAL-PROPERTIES, REINFORCED-CONCRETE, PORE SOLUTION, FLY-ASH, DURABILITY, MORTARS, CORROSION