Date of Award

12-2001

Level of Access Assigned by Author

Campus-Only Thesis

Degree Name

Master of Science (MS)

Department

Civil Engineering

Advisor

Roberto A. Lopez-Anido

Second Committee Member

Habib J. Dagher

Third Committee Member

William G. Davids

Abstract

A hybrid panel made of Fiber -Reinforced Polymer (FRP) and glued laminated wood (glulam) is proposed as a new bridge deck system. The FRP-glulam system is based on the concept of optimizing a bridge deck panel with FRP composite skins and a glulam core. Like conventional glulam decks, FRP-glulam panels can be used either as a longitudinal deck or as a transverse deck with respect to the bridge span direction.

In order to demonstrate FRP-glulam deck system in field applications, several challenging issues need to be addressed, as follows: (1) How to achieve an effective FRPwood composite section during the life term? (2) How to develop a fabrication method to be implemented by industry? (3) What is the difference in structural response between conventional glulam panels and FRP-glulam panels? (4) How to design this innovative deck system? (5) Is this new deck system economical compared to other existing deck systems, such as all-FRP decks and glulam decks?

To address the key issues identified, material, durability, and structural experiments were conducted. In addition, finite element analysis was performed and correlated to the experimental structural response. A design procedure for noninterconnected transverse FRP-glulam deck system was proposed based on LRFD bridge specifications and the current design method for glulam bridge decks. A fabrication method was developed in the laboratory and implemented by industry. Finally, a comparative cost analysis was presented.

The conclusions of the experimental and analytical study are: (1) Exposure to Chromated Copper Arsenate (CCA) preservative reduced the longitudinal tensile strength of unidirectional composite laminates; (2) A strong and durable FRP / CCA treated wood interface was achieved by appropriate surface preparation and application of Hydroxy Methylated Resorcinol (HMR) coupling agent on the wood surface; (3) Vacuum bagging was proven to be a practical, repeatable and cost-efficient method to laminate the FRP composite skin on glulam panels; (4) Reinforcing glulam panels with 1.4% by volume of FRP skin on each side, increased the bending stiffness by approximately 22.9%. Besides, FRP-glulam panels behaved more ductile than glulam panels. In addition, the failure load of FRP-glulam panels was approximately 35.7% higher than the corresponding one of glulam panels; (5) The cost of an FRP-glulam decks is approximately 80% of the cost of an all FRP composite deck. (6) FRP composite skins are expected to extend the life of glulam panels by providing environmental protection. (7) The polymer concrete overlay provides not only a wearing surface during construction, but also interfaces with the hot mix asphalt pavement.

The FRP-glulam panel was proven to be an attractive choice for bridge deck system with fast installation, lightweight, and ease of connection with other bridge components. The FRP-glulam panel system was demonstrated at Union-Washington Skidmore Bridge deck, which was constructed in October of 2001.

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