A Probabilistic-Based Durability Analysis of Concrete Structures Exposed to Chloride Containing Environment

2012 ◽  
Vol 204-208 ◽  
pp. 3282-3286
Author(s):  
Wei Hua Shi ◽  
Zhi Wu Yu ◽  
Ya Chuan Kuang
Keyword(s):  
Diffusion Coefficient ◽  
Life Prediction ◽  
Chloride Transport ◽  
Concrete Structures ◽  
Chloride Diffusion ◽  
Chloride Ingress ◽  
Chloride Diffusion Coefficient ◽  
Time Dependency ◽  
Durability Analysis

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.

Influence of the Pretreatment on the Concrete Chloride Diffusion Coefficient

2011 ◽  
Vol 477 ◽  
pp. 382-387
Author(s):  
Jia Cheng Li ◽  
Wen Ying Guo ◽  
Jing Wei Wu ◽  
Yi Bo Yang
Keyword(s):  
Diffusion Coefficient ◽  
Concrete Structures ◽  
Chloride Diffusion ◽  
Experimental Result ◽  
Chloride Diffusion Coefficient ◽  
Ultrasonic Bath ◽  
Vacuum Saturation ◽  
Chloride Migration ◽  
Relationship Of ◽  
The Relationship

The pretreatment of concrete rapid chloride migration coefficient (RCM) method in different standard is different in China. However the influence of pretreatment on the experimental result is uncertain, which leads to poor comparability about the results between different standards and trouble in evaluating the durability of concrete structures. The influence of the pretreatment on the chloride diffusion coefficient was studied by contrastive method. On the base of the results a suitable pretreatment of RCM method was proposed. The results are as followings: (1) the influence of pretreatment on the chloride migration coefficient of concrete with 0.45 W/B is insignificant. The influence of pretreatment on the chloride migration coefficient of concrete with other W/B is significant, and the influence increase with the lower w/b.; (2) the chloride diffusion coefficient will increase after the ultrasonic bath and vacuum saturation, and the influence of the ultrasonic bath is larger. Considering the judgment to the durability of structure, the ultrasonic bath and the vacuum saturation are suggested to be used; (3) on the condition of the same anode and cathode solution, the chloride diffusion coefficient in accordance with JTG / T B07-01-2006 standard is usually higher than that in accordance with GB/T50082-2009 standard; (4) the relationship of the chloride diffusion coefficient between mortar and concrete specimens is uncertain under different proportion and curing system, so the mortar specimens can not replace the concrete specimens for the RCM method.

scholarly journals Investigation on Numerical Simulation of Chloride Transport in Unsaturated Concrete

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Qingzhang Zhang ◽  
Feng Wang ◽  
Yifeng Ling ◽  
Hui Chen ◽  
Zhongyuan Li
Keyword(s):  
Diffusion Coefficient ◽  
Relative Humidity ◽  
Moisture Absorption ◽  
Chloride Transport ◽  
Salt Spray ◽  
Chloride Diffusion ◽  
Transfer Model ◽  
Chloride Diffusion Coefficient ◽  
Desorption Process ◽  
Water Equilibrium

Marine atmosphere environment accelerates the process of chloride penetration into concrete under the coupling effect of ambient temperature and relative humidity, thereby reducing the durability and service life of concrete. This paper aims to investigate the change of water equilibrium saturation and the chloride transport properties of concrete materials in different environments. The water equilibrium saturation tests at three temperatures and five relative humidity (RH) and salt spray erosion tests at three temperatures were performed. The influence of RH and temperature on the equilibrium saturation of concrete and the influence of temperature and time on the chloride diffusion coefficient are investigated. The results show that, in the process of moisture absorption and desorption, the equilibrium saturation of concrete gradually decreases as temperature rises. At the same depth of concrete, the chloride content gradually increases with temperature increasing, as well as the chloride diffusion coefficient. However, as the corrosion time of salt spray increases, the altering of chloride diffusion coefficient becomes less. Based on the Kelvin equation, a relationship between capillary pressure and water saturation in concrete was established, and a moisture transfer model for concrete in the process of moisture absorption and desorption was derived. Further, based on the established chloride diffusion equation and heat balance equation, a model of temperature-wet-chloride coupling chloride transfer was derived. Theory model simulation results show the transfer speed of chloride under the coupling of diffusion and capillary is higher than pure diffusion in moisture in the absorption process. However, the opposite is true in the desorption process. Moreover, with the increment of saturation rate, the capillary effect on chloride transport is enhanced.

Microstructure Analysis on LILW Waste Disposal Facility by Accelerated Steel Corrosion Tests

2013 ◽  
Vol 378 ◽  
pp. 194-197
Author(s):  
Ki Beom Kim ◽  
Jang Hwa Lee ◽  
Do Gyeum Kim
Keyword(s):  
Diffusion Coefficient ◽  
Waste Disposal ◽  
Concrete Structures ◽  
Steel Corrosion ◽  
Microstructure Analysis ◽  
Chloride Diffusion ◽  
Chloride Diffusion Coefficient ◽  
Reinforcing Bar ◽  
Disposal Facility ◽  
Chloride Attack

Concrete structures such as LILW waste disposal facility located near the sea may suffer from chloride attack damages. This study aims to analysis mock-up test for acceleration corrosion of reinforcing bar and its deterioration in concrete structures by XRD and chloride diffusion coefficient. Corrosion acceleration experiment test has been developed and used to evaluate the effect of corrosion of reinforcing bar caused by seawater on engineered barrier of LILW waste disposal facility.

Sign in / Sign up

Export Citation Format

Share Document