Type of Document	Dissertation
Author	Liu, Youping
URN	etd-44541620119653540
Title	Modeling the Time-to Corrosion Cracking of the Cover Concrete in Chloride Contaminated Reinforced Concrete Structures
Degree	PhD
Department	Civil Engineering
Advisory Committee	Advisor Name Title Richard E. Weyers Committee Chair Imad L. Al-Qadi none Jesse J. Brown, Jr. none Richard D. Walker none Richard M. Barker none
Keywords	cracking corrosion chloride deterioration model
Date of Defense	1996-10-21
Availability	unrestricted
Abstract Significant factors on steel corrosion in chloride contaminated reinforced concrete and time-to-corrosion cracking were investigated in this study. Sixty specimens were designed with seven admixed chloride contents, three concrete cover depths, two reinforcing steel bar diameters, two exposure conditions, and a typical concrete with water to cement ratio of 0.45. Corrosion current density (corrosion rate), corrosion potential, ohmic resistance of concrete and temperature were measured monthly on these specimens using both the 3LP and Gecor devices. Metal loss measurements were performed in accordance with ASTM G1-90, method C3.5, after specimens cracked. The actual corrosion weight loss of the steel reinforcing bars was then compared to the result obtained from the corrosion rate measurement devices. An interaction model for characterizing the dynamic corrosion process was developed based on the five-year corrosion database. The model demonstrates that the corrosion rate is a function of chloride content, temperature at reinforcement depth, ohmic resistance of concrete, and corrosion time after initiation. A time-to-corrosion cracking model was suggested based on a corrosion-cracking conceptual model and critical mass of corrosion products. The model predicted times to corrosion cracking are in good agreement with the observed times to corrosion cracking of the cover concrete.
Files	Filename       Size       Approximate Download Time (Hours:Minutes:Seconds)     28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access    etd.pdf 2.34 Mb 00:10:49 00:05:34 00:04:52 00:02:26 00:00:12   Liu.pdf 2.34 Mb 00:10:49 00:05:34 00:04:52 00:02:26 00:00:12

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