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EPOXY COATED REINFORCEMENT STUDY Andrew Griffith, P.E. and H. Martin Laylor, Oregon Department of Transportation Research Group CORROSION OF EPOXY COATED REBAR IN FLORIDA BRIDGES Alberto A. Sagues, Department of Civil Engineering and Mechanics, College of Engineering, University of South Florida, Tampa FIELD PERFORMANCE OF EPOXY-COATED REINFORCING STEEL IN VIRGINIA BRIDGE DECKS Wioleta Agata Pye, Faculty of the Virginia Polytechnic Institute and State University Fiber-Reinforced Polymer Bridge Decks – Status Report and Future Prospects Prof. Dr. Thomas Keller, Composite Construction Laboratory, Swiss Federal Institute of Technology BRIDGE STRENGTHENING WITH ADVANCED COMPOSITE SYSTEMS Heinz Meier, Sika Services AG, Zürich, Switzerland

A remarkable drawing dated December 1889 This artist saw already a vision of the San Fransisco Bay with a miracle-bridge. He called his drawing: A View of San Fransisco in the year 1929. he was only seven years off the mark. Apart from the bridge he predicted the helicopter, allthough these look rater different in reality that he envisioned. Also escaping his visionary capabilities are the skyscrapers! Source: From Coast to Coast (Van Kust tot Kust), a book by Rudolf van Reest. The book ia about a round trip in the United States of America. The book was printed in 1948.

EPOXY COATED REINFORCEMENT STUDY Andrew Griffith, P.E. and H. Martin Laylor, Oregon Department of Transportation Research Group OVERVIEW This report evaluates the use of Scotchlite 213 epoxy coated reinforcement in Oregon coastal environments. There is an extensive body of knowledge documenting epoxy coated reinforcement research in North America in the last 20 years. The research has produced mix results. However, recent studies conducted by Clear and others for the National Cooperative Highway Research Program, by Kessler and others for the Florida Department of Transportation and by Weyers and others in Virginia, provide evidence of poor performance of epoxy coated reinforcement in coastal bridge structures. In 1989, the Oregon Department of Transportation removed a concrete test beam reinforced with Scotchlite 213 epoxy coated reinforcement after nine years of service from Yaquina Bay in Newport, Oregon. Results of the testing and evaluation showed that there was adhesion loss of the coating attributed to low blast profile of the steel and low coating thickness. There was observed corrosion along the longitudinal bars and hoop reinforcement that were located within the tidal zone. Another concrete beam reinforced with Scotchlite 213 epoxy coated reinforcement was removed from Yaquina Bay in 1998 after eighteen years of exposure. The testing and evaluation showed that: 1. Half-cell potential measurements within the beam’s tidal zone exceeded the 90% probability threshold (-0.35 V) for corrosion to occur. 2. The chloride concentrations were significantly elevated within the beam’s tidal zone. 3. The adhesion loss was greatest within the tidal zone and in some areas, there was total loss of adhesion. 4. Most of the observed corrosion of the Scotchlite 213 epoxy coated reinforcement was within the tidal zone. Based on the literature documenting previous studies and ODOT’s testing and evaluation conducted in 1989 and in 1998, the use Scotchlite 213 epoxy coated reinforcement for long term protection against corrosion in coastal bridges is not recommended.
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CORROSION OF EPOXY COATED REBAR IN FLORIDA BRIDGES Alberto A. Sagues, Department of Civil Engineering and Mechanics, College of Engineering, University of South Florida, Tampa OVERVIEW Report determining the present condition of Florida bridges built with Epoxy-Coated rebar and establishing a prognosis for the future corrosion-related durability of these structures.
The full article can be downloaded here as a PDF file. It is 1.0 MB.

FIELD PERFORMANCE OF EPOXY-COATED REINFORCING STEEL IN VIRGINIA BRIDGE DECKS Wioleta Agata Pye, Faculty of the Virginia Polytechnic Institute and State University OVERVIEW The corrosion protection performance of epoxy-coated reinforcing steel (ECR) was evaluated in 18 concrete bridge decks in Virginia in 1997. The decks were 2 to 20 years old at the time of the investigation. The concrete bridge deck inspections included crack survey and cover depth determination in the right traffic lane. Maximum of 12 cores with the top reinforcement randomly located in the lowest 12 th percentile cover depth and 3 cores with the truss bars were drilled from each bridge deck. The concrete core evaluation included visual examination and determination of carbonation depth, moisture content, absorption, percent saturation and chloride content at 13 mm depth. Rapid chloride permeability test was also performed for the surface and base concrete on samples obtained from cores containing truss bars. The ECR inspection consisted of visual examination and damage evaluation, coating thickness and adhesion determination. The condition of the steel underneath the epoxy coating was also evaluated. Adhesion loss of the epoxy coating to the steel surface was detected for 4 years old bridge decks. The epoxy coating had debonded from the reinforcing bar before the chloride arrival. Visible signs of a possibility of a corrosion process underneath the coating suggest that ECR will not provide any or little additional service life for concrete bridge decks in comparison to black steel. Other systems, which will provide longer protection with a higher degree of reliability against chloride induced corrosion of steel in concrete, should be considered.
The full article can be downloaded here as a PDF file. It is 1,2 MB.

Fiber-Reinforced Polymer Bridge Decks – Status Report and Future Prospects Prof. Dr. Thomas Keller, Composite Construction Laboratory, Swiss Federal Institute of Technology OVERVIEW Fiber-reinforced polymers (FRP) are developing to be a promising alternative construction material for bridge decks today. The favorable characteristics of FRP bridge decks are a high strength combined with a small dead load and a large tolerance for frost and de-icing salts. The small dead load of approximately 20% of a concrete deck enables short installation times of the prefabricated panels with minimum traffic interference as well as a possible increase in the allowable live loads of existing bridges via replacement of the heavy concrete decks. Furthermore, construction details can be designed much simpler compared to concrete decks. The waterproofing layer and the associated complicated parapet detailing are not necessary. Different deck systems have already been developed and a multitude of demonstration projects with small spans up to 10 m have been installed [1]. In principle, two construction forms are used: multi-cellular deck panels from adhesively bonded pultruded shapes and sandwich panels with different core structures. Stiffened foams or thin walled cellular materials are most commonly used for the cores. Most of the bridges constructed to date, however, use multi-cellular pultruded deck systems. The panels consist of differently-shaped cross-sections: hexagonal plus half-depth trapezoidal sections, triangular single or dual-cell sections, box sections as well as trapezoidal dual-cell sections (see Fig. 1). The joints between the deck panels are usually adhesively bonded while mechanical connections between deck panels and main girders are used (shear studs for steel and stirrups for concrete girders, see Fig. 1). However, the mechanical deck-to-girder connections show several disadvantages. The concentrated load introduction points can lead to high local stress concentrations and the necessity of cutting holes in the decks can affect the durability. Therefore, research is conducted on adhesively bonded connections between decks and girders. Adhesively bonded connections on the whole top surface of the girders enable a smooth load transfer from the girders to the decks showing only small shear and peeling stresses. A good static, creep and fatigue behavior of such connections resulted from experiments on full-scale adhesively bonded FRP/steel-girders (see Fig. 2 and [2]). The adhesive bond provided full composite action between FRP bridge decks and steel girders and resisted 10 million loading cycles according to Eurocode fatigue loads without any signs of damage or stiffness loss.
The full article can be downloaded here as a PDF file. It is 146,7 kB.

BRIDGE STRENGTHENING WITH ADVANCED COMPOSITE SYSTEMS Heinz Meier, Sika Services AG, Zürich, Switzerland Reto Clenin, Sika Services AG, Zürich, Switzerland Miklos Basler, Sika Services AG, Zürich, Switzerland Summary It is becoming preferable, both environmentally and economically to upgrade bridges rather than to demolish and rebuild them. Deterioration of bridges wear from environmental influences and from traffic loads require rehabilitation and renewal programs to maintain even current service levels on the bridge infrastructure network. Demands for high durability, longer service life, reduced maintenance cost and cost/performance optimised. System solution have prompted a new look at Advanced Composite Systems. This paper presents the evolution of CarboDur Composite Systems from its start in 1991, relevant test reports for bridge engineering as well as their world-wide application.
The full article can be downloaded here as a PDF file. It is 7,9 kB.
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