Condition Evaluation of Concrete Bridges Relative to Reinforcement Corrosion

Condition Evaluation of Concrete Bridges Relative to Reinforcement Corrosion
Author: Stephen E. Herald
Publisher:
Total Pages: 155
Release: 1993
Genre: Concrete bridges
ISBN:

This report deals with the selction of a method and the development of detailed procedures to accurately measure the chloride content of reinforced concrete in the field. Specific ion probe, spectrophotometer, digital titrator, and quantab titrator stips were the methods investigated. Results from laboratory procedures and evaluation based on cost, speed accuracy, and levels of required expertise indicated that the specific ion probe was more suitable for use in the field than the other methods selected. Field validation testing was done to substantiate laboratory findings. Guidelines were produced for the instrumentation, digestion solution, and test procedure. The enhanced procedures were evaluated.

Long-term Performance of Corrosion Inhibitors Used in Repair of Reinforced Concrete Bridge Components

Long-term Performance of Corrosion Inhibitors Used in Repair of Reinforced Concrete Bridge Components
Author: Moavin Islam
Publisher: DIANE Publishing
Total Pages: 58
Release: 2003
Genre: Concrete bridges
ISBN: 1428995242

The primary objective of the project was to determine the effectiveness of cathodic protection, electrochemical chloride extraction, and corrosion-inhibitor treatment systems installed during the SHRP effort through the long-term evaluation of 32 field test sites and a number of laboratory concrete slab specimens. The FHWA program required monitoring the long-term performance of corrosion inhibitor treatments on selected components of four bridges that were treated and evaluated under SHRP C-103. Three evaluations over a period of 5 years were conducted on structures located in Minnesota, New York and Pennsylvania, and two evaluations were conducted on a structure in Washington State. An analysis of the results concluded that neither of the corrosion inhibitors evaluated in this study, using the specified repairs and exposed to the specific environments, provided any corrosion-inhibiting benefit. Shrinkage cracking plagued repairs at all test sites except for the Washington site.

Evaluation of Electrochemical Chloride Extraction, Fiber Reinforced Polymer Wraps, and Concrete Sealers for Corrosion Mitigation in Reinforced Concrete Bridge Structures

Evaluation of Electrochemical Chloride Extraction, Fiber Reinforced Polymer Wraps, and Concrete Sealers for Corrosion Mitigation in Reinforced Concrete Bridge Structures
Author: Michael S. Murphy
Publisher:
Total Pages: 155
Release: 2019
Genre: Chlorides
ISBN:

Reinforced concrete bridge substructures in Minnesota and other northern climates possess an elevated risk for chloride induced corrosion damage, which can reduce capacity and shorten service life. Research was performed in 1997 to investigate new strategies for corrosion mitigation, including electrochemical chloride extraction (ECE) and installation of fiber reinforced polymer (FRP) wrap, which were applied on several corrosion-damaged piers on a 30-year-old bridge in Minneapolis. This report presents the results of follow-up research performed to assess the condition of the treated piers after 20 additional years of service, in order to understand the long-term effectiveness of the strategies implemented. The combination of ECE treatment and FRP wrap installation was found to be very effective, with no concrete distress or probable corrosion activity identified in the treated elements. Poor or mixed performance was observed with all other strategies, including both ECE treatment followed by application of a penetrating sealer and FRP wrap installation that was not accompanied with ECE. In addition, significant chloride contamination occurred in all of the subject piers within the 20 years since the initial study, indicating that neither FRP wrap nor concrete sealers prevented the ingress of new chlorides in the manner in which these systems were installed in the initial study. The findings indicated that performing ECE treatment, or installing FRP wraps, did not alone eliminate the risk of future corrosion activity. The most effective corrosion mitigation strategy to extend the service life of reinforced concrete bridge substructures was to minimize water and chloride exposure.

Corrosion of Steel in Concrete

Corrosion of Steel in Concrete
Author: John P. Broomfield
Publisher: CRC Press
Total Pages: 305
Release: 2023-01-31
Genre: Technology & Engineering
ISBN: 1000822486

Corrosion of Steel in Concrete: Understanding, Investigation and Repair is a guide for designing, constructing and maintaining reinforced concrete structures, such as buildings and bridges which are subject to reinforcement corrosion. It presents the basics of theory and practice in steel corrosion in concrete and reviews the latest research and developments, such as progress on measuring the corrosion threshold for chloride-induced corrosion. This third edition compares the currently proliferating major national and international standards and guidance documents. New developments are considered, such as hybrid anodes for electrochemical treatment and the latest research and developments in assessment, such as the use of ground penetrating radar to measure the chloride content of the concrete cover. It overhauls coverage of electrochemical repair and rehabilitation techniques and outlines recent innovations in structural repair and construction and investigates their implications for durability. The book is ideal for practitioners and graduate students in structural engineering and concrete technology.

Evaluation of Corrosion Protection Methods for Reinforced Concrete Highway Structures

Evaluation of Corrosion Protection Methods for Reinforced Concrete Highway Structures
Author: Jennifer L. Kepler
Publisher:
Total Pages: 244
Release: 2000
Genre: Concrete bridges
ISBN:

Since the 1970s, research projects and field studies have been conducted on different methods for protecting reinforced concrete bridges from corrosion damage. The methods include alternative reinforcement and slab design, barrier methods, electrochemical methods, and corrosion inhibitors. Each method and its underlying principles are described, performance results of laboratory and/or field trials are reviewed, and systems are evaluated based on the results of the trials. Using performance results from the studies and costs obtained from transportation agencies, an economic analysis is used to estimate the cost of each system over a 75-year economic life using discount rates of 2%, 4% and 6%.