Time and spatially dependent transient competitive antagonism during the 2-D diffusion-reaction of combined chloride-sulphate attack upon concrete. (April 2022)

• Record Type: Journal Article
• Authors: Chen, Zheng; Yu, Jiamin; Bindiganavile, Vivek; Yi, Chaofan; Shi, Caijun; Hu, Xiang
• Is Part Of: Cement and concrete research. Volume 154(2022)
• Publication Date: 2022-04
• Subjects: Competitive antagonism -- Concrete -- Coupled models -- Chloride -- Sulphate -- Time and spatial dependence; Cement -- Periodicals; Cement -- Research -- Periodicals; Concrete -- Periodicals; Concrete -- Research -- Periodicals; Ciment -- Périodiques; Béton -- Périodiques; Cement; Concrete; Periodicals; 620.135
• DOI: 10.1016/j.cemconres.2022.106724
• Languages: English
• ISSNs: 0008-8846

Abstract

Abstract: The long-term impact of competitive antagonism of the combined chloride-sulphate attack upon structural concrete is difficult to determine experimentally. In this study, a pair of time and spatially dependent models is proposed to study the diffusion-reaction of the combined chloride-sulphate attack. The competitive antagonism is quantified as Δ C cl and Δ strain respectively, for the chloride and sulphate induced attacks. The results reveal that the competitive antagonism clearly shows both a time- and a spatial-dependence. The competition between them is minimal in the early stages of exposure and also, at depths closer to the surface. It increases and reaches a peak with an increase in the duration of exposure and the depth inside the specimen, before decaying gradually. The proposed models, therefore, predict a transient competitive antagonism. A sensitivity analysis was carried out, which shows that the combined chloride-sulphate attack itself and the ensuing competitive antagonism are both most sensitive to the water-to-cement ratio and, to a lesser extent, to the instantaneous calcium aluminate content in the binder.