Application of Cathodic Prevention in a New Concrete Bridge Deck in Virginia

Application of Cathodic Prevention in a New Concrete Bridge Deck in Virginia
Author: Gerardo G. Clemeña
Publisher:
Total Pages: 46
Release: 2003
Genre: Concrete bridges
ISBN:

Corrosion of reinforcement in concrete bridges has been a major factor in limiting the service life of many such structures. As part of a concerted effort to identify cost-effective options for eliminating corrosion of reinforcement, the application of cathodic prevention was tried in a recently constructed concrete bridge deck. The incorporation of an impressed-current cathodic prevention system in a new concrete bridge deck while it was being constructed was made possible by the use of titanium mesh ribbon anodes coated with mixed-metal oxide. The anodes were spaced 32 cm (13 in.) apart and transversely across the entire bridge deck to allow for the trouble-free placement of the concrete. The system has been operating for almost 2 years with no extraordinary problems. A comparison of the long-term cost of this option with those of other options, such as the use of corrosion-resistant clad bars or stainless steel bars, indicated that this option is not economically favorable.

A Slotted Cathodic Protection System for Bridge Decks

A Slotted Cathodic Protection System for Bridge Decks
Author: Gerardo G. Clemeña
Publisher:
Total Pages: 31
Release: 1985
Genre: Bridges
ISBN:

A non-overlay, slotted cathodic protection system was installed two years ago on a concrete bridge deck in Virginia. The design, installation, and operation of this system are fairly straightforward. A protective current density of 1.6 mA/ft2 (17 mA/m2) as determined by E-log I curves has been applied constantly on the deck. Various tests have shown that polarization of the structure has been achieved. After more than 18 months in service, the various components of this system appeared to be in good condition.

Cathodic Protection of Concrete Bridge Decks Using Titanium-mesh Anodes

Cathodic Protection of Concrete Bridge Decks Using Titanium-mesh Anodes
Author: Gerardo G. Clemeña
Publisher:
Total Pages: 22
Release: 2000
Genre: Anodes
ISBN:

Anodes are a critical component of cathodic protection systems. A continuous research effort in Virginia is being aimed at searching for the most suitable anode for use in cathodic protection of the various types of concrete bridge components that are exposed to intrusion by chloride ions. As part of this effort, three different catalyzed titanium mesh anodes were tested, side by side, in a cathodic protection system that was designed and constructed (in conjunction with the rehabilitation of several concrete deck spans) to prevent further reinforcement corrosion-related damage to these structures. The purpose of this study was to determine whether this type of new anode is suitable for application in bridge decks, and if any of the three mesh anodes tested in this study excels over the other. It was observed during construction that the installation of these mesh anodes is compatible with the normal construction procedures involved in the rehabilitation of bridge decks. Observations made during the first four years of operation indicated that, among all the different types of anodes tested to date for bridge decks, the three mesh anodes tested in this study were the most effective. These newly tested anodes probably have a considerably longer service life than other anodes that have been tested to date. Furthermore, there was no significant difference in the operational characteristics of the three mesh anodes tested in this study.

Pilot Applications of Electrochemical Chloride Extraction on Concrete Bridge Decks in Virginia

Pilot Applications of Electrochemical Chloride Extraction on Concrete Bridge Decks in Virginia
Author: Gerardo G. Clemeña
Publisher:
Total Pages: 38
Release: 1996
Genre: Bridges
ISBN:

A recent SHRP study confirmed that applying an electrical field between the surface of a concrete structure and the rebars (like cathodic protection, except with 50 to 500 times more current) can expel the chloride ions from salt-contaminated reinforced concrete and mitigate rebar corrosion. This new rehabilitation method was tried on two whole deck spans, as part of pilot trials in Virginia to demonstrate the practicality of this electrochemical chloride extraction (ECE) process on full-sized bridge elements and to help refine the technique. The total concrete area treated was approximately 720 m 2 (7,750 ft2). To avoid traffic interruption, half of the deck was treated at a time (for 8 weeks, though a shorter time would likely suffice). The treatment used a very simple installation and procedure, involving placement of a temporary electrolyte-soaked anode system (of inert catalyzed titanium mesh sandwiched between two layers of felt) on the surface of the deck, and the application of total charges that varied between 741 to 1,077 A-hr/m 2 (68.8 to 100.1 A-hr/ft 2) in 57 to 58 days between the anode and the rebars. Approximately 72.2 to 82.1% of the initial chloride ions were removed from the concrete in various depths. These magnitudes surpassed the removal rate of 40 to 50% that was suggested for very heavy treatment by one SHRP report. A minor rectifiable difficulty was encountered in neutralizing the acidity generated in the electrolyte, especially during the first several days of each treatment phase. Lithium was used in the electrolyte for two portions of the deck and was observed to migrate readily into the concrete. However, a similar attempt to simultaneously inject a cationic corrosion inhibitor (tetraphenylphosphonium) into the concrete, which represented a first attempt ever on a concrete deck, yielded uncertain results. It is uncertain whether the corrosion inhibitor had migrated into the concrete; if it had, it was in quantities less than the minimum detection level of 25 ppm, by the capillary electrophoresis method used. Overall, the pilot treatment of the deck was judged to be very simple to perform and more than reasonably successful.

Cathodic Protection of Two Concrete Bridge Decks Using Titanium-mesh Anodes

Cathodic Protection of Two Concrete Bridge Decks Using Titanium-mesh Anodes
Author: Gerardo G. Clemeña
Publisher:
Total Pages: 9
Release: 1991
Genre: Concrete bridges
ISBN:

Expanded titanium mesh with a layer of precious metal oxides sintered around it has recently been introduced to fulfill the need for a durable anode in the cathodic protection (CP) of concrete bridge decks. In addition to being resistant to chemical attack, the titanium mesh (1) provides relatively high electrical redundancy, (2) requires minimal labor to install, and (3) is compatible with concrete overlays. To provide the Virginia Department of Transportation with an opportunity to observe and gain experience with the use of this promising type of anode, plans were formulated to use titanium mesh from three different manufacturers in a CP system as part of the rehabilitation of two existing concrete bridge decks that had salt-induced concrete deterioration.

Cathodic Protection of Concrete Bridges

Cathodic Protection of Concrete Bridges
Author: Jack E. Bennett
Publisher: Strategic Highway Research Program (Shrp)
Total Pages: 316
Release: 1993
Genre: Technology & Engineering
ISBN:

This document provides explanation, guidance, and direction concerning cathodic protection of concrete bridge elements to the highway engineer who wants to incorporate cathodic protection in a bridge project. The manual which provides background information on corrosion fundamentals, is divided into 3 parts: design, construction, and operation and maintenance. An appendix provides standard specifications for cathodic protection systems for both decks and substructures. The document is intended to be a useful reference for engineers who design and prepare specifications or who oversee turnkey operations.

Cathodic Protection of Steel in Concrete and Masonry

Cathodic Protection of Steel in Concrete and Masonry
Author: Paul M. Chess
Publisher: CRC Press
Total Pages: 250
Release: 2015-02-04
Genre: Technology & Engineering
ISBN: 0203938070

Revised and updated, this second edition of Cathodic Protection of Steel in Concrete and Masonry covers both reinforced concrete and masonry structures, describes in detail the overall design factors involved in cathodic protection (CP), and also provides a theoretical basis for why it works. It refers to the new European standard EN 12696 for cath

Proceedings of the Conference on Cathodic Protection of Reinforced Concrete Bridge Decks, San Antonio, Texas, February 12-13, 1985

Proceedings of the Conference on Cathodic Protection of Reinforced Concrete Bridge Decks, San Antonio, Texas, February 12-13, 1985
Author:
Publisher:
Total Pages: 294
Release: 1985
Genre: Technology & Engineering
ISBN:

The conference focused on the major problem facing highway and bridge engineers: deterioration of concrete bridge decks caused by corrosion of the reinforcing steel. The conference was aimed primarily at giving bridge owners and engineers an understanding of cathodic protection as the only means to stop corrosion on bridge decks.