Investigation on Relationship Between Long Term and Short Term Tests of Chloride Diffusion Coefficient

Time dependency of chloride transport has been studied and an improving model for predicting the apparent chloride diffusion coefficient has been proposed. A probabilistic-based durability analysis to estimate failure probability on the chloride ingress into concrete has been carried out. Results of the analysis demonstrate that the improving model in this paper is appropriate for long term service life prediction of concrete structures exposed to chloride containing environment.

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Chloride diffusion coefficient through porous materials : a disturbing parameter

2nd International RILEM Symposium on Advances in Concrete through Science and Engineering ◽

10.1617/2351580028.017 ◽

2006 ◽

Author(s):

Pascale Bégué

Keyword(s):

Diffusion Coefficient ◽

Porous Materials ◽

Chloride Diffusion ◽

Chloride Diffusion Coefficient

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Ageing effect of chloride diffusion coefficient

ConcreteLife'06 - International RILEM-JCI Seminar on Concrete Durability and Service Life Planning: Curing, Crack Control, Performance in Harsh Environments ◽

10.1617/291214390x.005 ◽

2006 ◽

Cited By ~ 2

Author(s):

G.C.M. Gaal

Keyword(s):

Diffusion Coefficient ◽

Chloride Diffusion ◽

Chloride Diffusion Coefficient ◽

Ageing Effect

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Experimental Study on Effective Chloride Diffusion Coefficient of Cement Mortar by Different Electrical Accelerated Measurements

Crystals ◽

10.3390/cryst11030240 ◽

2021 ◽

Vol 11 (3) ◽

pp. 240

Author(s):

Jianlan Chen ◽

Jiandong Wang ◽

Rui He ◽

Huaizhu Shu ◽

Chuanqing Fu

Keyword(s):

Diffusion Coefficient ◽

Cement Mortar ◽

Early Stage ◽

Chloride Concentration ◽

Chloride Diffusion ◽

Chloride Diffusion Coefficient ◽

Cement Ratio ◽

Water To Cement Ratio ◽

Good Consistency ◽

Determination Methods

This study investigated the effective chloride diffusion coefficient of cement mortar with different water-to-cement ratio (w/c) under electrical accelerated migration measurement. The cumulative chloride concentration in anode cell solution and the cumulative chloride concentration drop in the cathode cell solution was measured by RCT measurement and the results were further used to calculate the chloride diffusion coefficient by Nordtest Build 355 method and Truc method. The influence of w/c on cement mortar’s chloride coefficient was investigated and the chloride diffusion coefficient under different determination methods were compared with other researchers’ work, a good consistency between this work’s results and literatures’ results was obtained. The results indicated that the increased w/c of cement mortar samples will have a higher chloride diffusion coefficient. The cumulative chloride concentration drop in the cathode cell solution will have deviation in early stage measurement (before 60 h) which will result in overestimation of the effective chloride diffusion coefficient.

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Effects after 1500 Hardening Days on the Microstructure and Durability-Related Parameters of Mortars Produced by the Incorporation of Waste Glass Powder as a Clinker Replacement

Sustainability ◽

10.3390/su13073979 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3979

Author(s):

Rosa María Tremiño ◽

Teresa Real-Herraiz ◽

Viviana Letelier ◽

Fernando G. Branco ◽

José Marcos Ortega

Keyword(s):

Diffusion Coefficient ◽

Water Absorption ◽

Glass Powder ◽

Cementitious Materials ◽

Cement Industry ◽

Waste Glass ◽

Supplementary Cementitious Materials ◽

Chloride Diffusion ◽

Chloride Diffusion Coefficient ◽

Waste Glass Powder

One of the ways of lessening the CO2 emissions of cement industry consists of replacing clinkers with supplementary cementitious materials. The required service life of real construction elements is long, so it is useful to characterize the performance of these materials in the very long term. Here, the influence of incorporating waste glass powder as a supplementary cementitious material, regarding the microstructure and durability of mortars after 1500 hardening days (approximately 4 years), compared with reference mortars without additions, was studied. The percentages of clinker replacement by glass powder were 10% and 20%. The microstructure was studied using impedance spectroscopy and mercury intrusion porosimetry. Differential thermal and X-ray diffraction analyses were performed for assessing the pozzolanic activity of glass powder at the end of the time period studied. Water absorption after immersion, the steady-state diffusion coefficient, and length change were also determined. In view of the results obtained, the microstructure of mortars that incorporated waste glass powder was more refined compared with the reference specimens. The global solid fraction and pores volume were very similar for all of the studied series. The addition of waste glass powder reduced the chloride diffusion coefficient of the mortars, without worsening their behaviour regarding water absorption after immersion.

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Influence of Hydrostatic Pressure and Cationic Type on the Diffusion Behavior of Chloride in Concrete

Materials ◽

10.3390/ma14112851 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2851

Author(s):

Huanqiang Liu ◽

Linhua Jiang

Keyword(s):

Diffusion Coefficient ◽

Hydrostatic Pressure ◽

Diffusion Model ◽

Coupling Effect ◽

Experimental Results ◽

Chloride Diffusion ◽

Concrete Durability ◽

Chloride Diffusion Coefficient ◽

Diffusion Behavior ◽

Diffusion Source

The durability of the concrete in underground and marine engineering is affected by the underground and ocean environment. Chloride diffusion coefficient under hydrostatic pressure is a key parameter of concrete durability design under corresponding conditions. Therefore, this paper studies the diffusion behavior of chloride in different diffusion source solutions by experiment and simulation. Based on the experimental results, this paper proposes a new chloride diffusion model under the coupling effect of diffusion and convection. The interaction of ions and compounds in the diffusion source solutions, concrete pore fluid, and concrete material are considered in the new chloride diffusion model. The experimental results show that chloride diffusion rate is significantly affected by hydrostatic pressure, which increases with the increase of hydrostatic pressure. The chloride diffusion coefficient shows a certain difference in difference diffusion source solutions. The chloride diffusion coefficient in divalent cationic diffusion source solutions is the largest, the chloride diffusion coefficient in the divalent and monovalent cationic compound ones is in the middle, and the chloride diffusion coefficient in the monovalent cationic ones is the smallest. There is a linear relationship between the chloride diffusion coefficient and the hydrostatic pressure whether in single or combined cationic diffusion source solutions.

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MODELLING CHLORIDE DIFFUSION IN CONCRETE WITH INFLUENCE OF CONCRETE STRESS STATE

Journal of Civil Engineering and Management ◽

10.3846/13923730.2017.1343203 ◽

2017 ◽

Vol 23 (7) ◽

pp. 955-965 ◽

Cited By ~ 3

Author(s):

Jian WANG ◽

Pui-Lam NG ◽

Weishan WANG ◽

Jinsheng DU ◽

Jianyong SONG

Keyword(s):

Experimental Data ◽

Diffusion Coefficient ◽

Stress State ◽

Diffusion Model ◽

Stress Ratio ◽

Chloride Diffusion ◽

Influence Coefficient ◽

Chloride Diffusion Coefficient ◽

Stress Influence ◽

Concrete Stress

Under coastal or marine conditions, chloride erosion is the major accelerating factor of reinforcement corrosion. Therefore, it is of vital importance to investigate the chloride diffusion model. Research reveals that the concrete stress state has great influence on chloride diffusion; therefore a stress influence coefficient was incorporated in chloride diffusion coefficient model by many researchers. By referring to the experimental data from eight different researchers, the law between stress influence coefficient and concrete stress ratio is studied in detail, and equations relating the stress influence coefficient with the concrete stress ratio are established. Compared with three typical existing groups of equations, it is found that the proposed equations give the most accurate estim.ation of the stress influence coefficient. Hence, the proposed equations can be adopted to improve the valuation of chloride diffusion coefficient, and a modified chloride diffusion model is put forward. Three groups of experimental data are used to validate the modified chloride diffusion model, which is shown to be reasonable and having high prediction accuracy.

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