Fiber-reinforced Polymer Composite Bridge Research Articles

Structural Behavior of FRP Composite Bridge Deck Panels

Fiber-reinforced polymer (FRP) composite bridge deck panels are high-strength, corrosion resistant, weather resistant, etc., making them attractive for use in new construction or retrofit of existing bridges. This study evaluated the force-deformation responses of FRP composite bridge deck panels under AASHTO MS 22.5 (HS25) truck wheel load and up to failure. Tests were conducted on 16 FRP composite deck panels and four reinforced concrete conventional deck panels. The test results of FRP composite deck panels were compared with the flexural, shear, and deflection performance criteria per Ohio Department of Transportation specifications, and with the test results of reinforced concrete deck panels. The flexural and shear rigidities of FRP composite deck panels were calculated. The response of all panels under service load, factored load, cyclic loading, and the mode of failure were reported. The tested bridge deck panels satisfied the performance criteria. The safety factor against failure varies from 3 to 8.

Durability of FRP Composite Bridge Deck Materials under Freeze-Thaw and Low Temperature Conditions

Fiber-reinforced polymer (FRP) composites, especially lightweight sandwich structures, are rapidly finding their way into civil infrastructure application. FRP composite panels are particularly attractive as bridge deck systems due to their high strength, low density, and durability, which are of importance to the bridge industry. Most of the vast amount of durability data for FRP has been generated for aerospace and automotive applications, which involve very different service conditions than civil infrastructure. For civil engineering applications, it is essential to examine the durability performance of FRP materials under weathering conditions. The ultimate goal of this research is to develop a reliable framework for durability assessment of FRP decks, including laboratory testing procedure and finite-element simulation capability. Such a framework should be applicable to all types of FRP deck construction. In this paper, specimens of typical FRP bridge deck skin materials are subjected to freeze-thaw cycling between 4.4 and –17.8°C in media of dry air, distilled water, and saltwater, and constant freeze at –17.8°C . The selected deck is used as an example for demonstration purposes. In addition, selected specimens are subjected to simultaneous environmental exposure conditions and sustained loading of 25% ultimate strain. It should be emphasized that most of the environmental conditions reported in the literature produce minor deterioration of a single composite property, and the assessment of such effect on this single property becomes unreliable because of a large property variation. Therefore, in this paper we use multiple mechanical properties as performance indices for damage evaluation. Based on findings from this work, it is concluded that freeze-thaw cycling between 4.4 and –17.8°C alone and up to 1,250 h and 625 cycles caused very insignificant or no change in the flexural strength, storage modulus, and loss factor of the FRP specimens conditioned in dry air, distilled water, and saltwater. Small reductions in storage modulus (about 1% or less) were observed when specimens were prestrained and subjected to 250 freeze-thaw cycles in distilled water and saltwater. Changes in flexural strength were statistically insignificant, since they were within the data scatter.

Dynamic Response of Three Fiber Reinforced Polymer Composite Bridges

Fiber reinforced polymer (FRP) composite bridge decks are gaining the attention of bridge owners because of their light self-weight, corrosion resistance, and ease of installation. Constructed Facilities Center at West Virginia University working with the Federal Highway Administration and West Virginia Department of Transportation has developed three different FRP decking systems and installed several FRP deck bridges in West Virginia. These FRP bridge decks are lighter in weight than comparable concrete systems and therefore their dynamic performance is equally as important as their static performance. In the current study dynamic tests were performed on three FRP deck bridges, namely, Katy Truss Bridge, Market Street Bridge, and Laurel Lick Bridge, in the state of West Virginia. The dynamic response parameters evaluated for the three bridges include dynamic load allowance (DLA) factors, natural frequencies, damping ratios, and deck accelerations caused by moving test trucks. It was found that the DLA f...

Web-Based Structural Health Monitoring of an FRP Composite Bridge

This paper describes how wireless technology was used in a structural health monitoring scheme to monitor the long-term performance of fiber reinforced polymer (FRP) composite bridge structures. The scheme was implemented on the Kings Stormwater Channel Bridge, located on a major state highway in California. The bridge was constructed using FRP composite girders and deck panels. The data collected by a comprehensive array of sensors are transmitted wirelessly, and processed in real-time remotely. Computer-based automated analysis algorithms process the incoming data to provide an assessment of structural response. Effects, due to time-based deterioration, and irregularities are determined using modal parameters, in terms of damage localization indices and an estimated damage severity. The results, made available via a web-based interface, enable appropriate action to be authorized for preliminary maintenance or emergency response prior to actual on-site inspection. This approach shows promise for monitoring and assessment of structural systems.

Laboratory and Field Performance of Cellular Fiber-Reinforced Polymer Composite Bridge Deck Systems

This paper addresses the laboratory and field performance of multicellular fiber-reinforced polymer (FRP) composite bridge deck systems produced from adhesively bonded pultrusions. Two methods of deck contact loading were examined: a steel patch dimensioned according to the AASHTO Bridge Design Specifications, and a simulated tire patch constructed from an actual truck tire reinforced with silicon rubber. Under these conditions, deck stiffness, strength, and failure characteristics of the cellular FRP decks were examined. The simulated tire loading was shown to develop greater global deflections given the same static load. The failure mode is localized and dominated by transverse bending failure of the composites under the simulated tire loading as opposed to punching shear for the AASHTO recommended patch load. A field testing facility was designed and constructed in which FRP decks were installed, tested, and monitored to study the decks’ in-service field performance. No significant loss of deck capacit...

Field performance of an FRP slab bridge

Fiber reinforced polymer (FRP) composite decks are new to bridge applications and hence not much literature exists on their in-service performance. The in-service performance, and impact and dynamic characteristics of the first fiber reinforced polymer composite bridge superstructure built in New York State in late 1998 are documented in this paper. Test data indicate that the superstructure and the shear-key are structurally performing well. The average impact factor was about 0.3. Observed low strains and deflections, compared to those predicted at the design stages, show room for optimization of the deck design to make these more cost-effective in the future. Higher modal damping values were observed and reflect the vibration absorbing capacity of FRPs. Several delaminations were found during visual inspections and the wearing surface was replaced once. For future applicability of FRPs for bridge deck applications, these issues affecting the long-term durability should be resolved.

Experience in the United States with Fiber-Reinforced Polymer Composite Bridge Decks and Superstructures

Research on the use of fiber-reinforced polymer (FRP) composite materials for bridge decks and superstructures has been ongoing since the 1980s. Vehicular bridges have been in service since 1996, and pedestrian bridges, longer than that. This paper focuses on vehicular bridges, of which many were funded by FHWA's Innovative Bridge Research and Construction Program or other funding initiatives. The objective is to summarize where the projects are, who supplied them, how they were constructed, what the benefits of using FRP were, what lessons can be learned, and what the projects cost. A review of this information should be useful to civil engineers or bridge owners who want to assess the state of the practice and make a judgment about using FRP for bridge decks or superstructures.

Joining techniques for fiber reinforced polymer composite bridge deck systems

Bridge decks made from fiber reinforced polymer (FRP) composites have been increasingly used in rehabilitation and new construction of pedestrian and highway bridges. For each application, connections are inevitable due to limitations on shape size and the requirements of transportation. Connections for FRP bridge decks include primary and secondary load-carrying joints and non-structural joints. Primary and secondary load-carrying connections are most concerned in construction, which include component–component connection, panel–panel connection, and deck-to-support connection. Unfortunately, the technical background, development and design guides of FRP bridge deck connections have not been documented adequately in literature. This paper attempts to provide technical background, developed joining techniques, and design principles concerning the joining of FRP decks. Design requirements, characteristics, performances, advantages and disadvantages of developed FRP deck connection techniques are discussed. Design principles for adhesively bonded joints and mechanical fixing and hybrid joints involving cutouts are also provided.

Close Look at Construction Issues and Performance of Four Fiber-Reinforced Polymer Composite Bridge Decks

Four different fiber-reinforced polymer (FRP) panel systems were installed in a 207 m, five-span, three-lane bridge in an effort to assess the constructability, performance, and applicability of bridges with fiber-reinforced polymer composite decks. This paper examines whether four common deck systems are able to realize many of the anticipated benefits of using FRP composites in lieu of conventional reinforced concrete bridge decks. Particular installation issues, connection details, and specific construction techniques for each deck system are described, along with a discussion of the shortcomings in terms of handling, performance, and serviceability. Other factors such as key design parameters (e.g., impact factor and thermal characteristics) and unexpected responses are used to further quantify the performance of four FRP representative deck systems under identical traffic and environmental constraints.

Connection of concrete barrier rails to FRP bridge decks

The paper investigates the viability of use of conventional joining concepts between reinforced concrete barrier rails to fiber-reinforced polymer composite bridge decks. The concept is tested and implemented as part of a FRP bridge system incorporating concrete filled carbon/epoxy shells as girders and a pultruded core E-glass/vinylester–polyester deck. The barrier was anchored into the deck using polymer concrete filled cavities within the deck at discrete locations. Experimental results indicated that the configuration provides excellent anchoring capacity and a mode of failure that is more stable and capable of greater energy absorption than the conventional system due to the encapsulation of the anchorage within the composite deck. Failure was initiated through yield in the bars at a load of 129 kN compared to a demand level of 44.5 kN. No damage accrues to the deck itself with minimal damage in the anchorage. Analytical predictions of onset of yield and failure are shown to match experimental results as well. The testing validates the use of the system pursuant to specification mandated criteria.

Fiber-Reinforced Polymer Composite Bridges in West Virginia

Fiber-reinforced polymer (FRP) composites have been used more often over the past decade than before in new construction as well as in repair of deteriorated bridges. Many of these bridges are on low-volume roads, where they receive very little attention. It is imperative that new bridge construction or repair be long lasting, nearly maintenance free, and as economical as possible. Relative to those factors, FRP composite bridges have been found to be structurally adequate and feasible because of their reduced maintenance cost and limited environmental impact (i.e., no harmful chemicals leaching into the atmosphere with longer service life). In West Virginia, 23 FRP composite bridges have been constructed, among which 18 are built on low-volume roads that have an average daily traffic (ADT) of less than 1,000, including 7 with ADT less than 400. General FRP composite bridge geometry and preliminary field responses are presented as are some of the preliminary construction specifications and cost data of FRP composite bridges built on low-volume roads in West Virginia

Advances in fibre‐reinforced polymer composite bridge decks

AbstractUtilization of thermoset or thermoplastic resins binding glass and/or carbon fabrics has led to advanced fibre‐reinforced polymer (FRP) composite materials, structural shapes, and systems. Innovative FRP composite bridge deck production processes have been developed and perfected. Two of these processes are pultrusion and resin transfer moulding. A number of structural systems implemented as bridge decks are described. Construction and design details of composite decks are also provided.

Vibration characteristics of a fiber-reinforced polymer bridge superstructure

Dynamic response of the first fiber-reinforced polymer composite bridge built in the US was studied using experimental modal tests and validated finite element models. This slab bridge was manufactured with a longitudinal joint, in the form of a shear-key, and was connected in the field using epoxy resins. Long-term performance of such joints is critical for future applications of similar designs. At the same time, the shear-key details are not visible, once joined, and cannot be inspected using routine inspection procedures. Hence, experimental modal analysis was used to evaluate the integrity of the longitudinal joint. A finite element model validated with field test data was developed to further study the effect of the longitudinal joint degradation on vibration characteristics of the structure. The finite element analysis was also used to evaluate the modal-based techniques for future inspections. Results indicate that the longitudinal joint is performing as intended, and only high degradation of the joint can be detected using the measured vibration characteristics of the bridge.

Design and Installation of Fiber-Reinforced Polymer Composite Bridge

This report describes the installation and testing of a fiber-reinforced polymer composite highway bridge located in Butler County, Ohio (U.S.). The bridge was designed to meet AASHTO HS-20 load requirements based on strength and maximum deflection. The installation demonstrated fiber-reinforced polymer composite highway bridges could be installed in significantly less time than a traditional reinforced concrete bridge. When fully loaded, the bridge deflected less than the maximum AASHTO HS-20 deflection values.

Design of Falls Creek Trail Bridge: A Fiber Reinforced Polymer Composite Bridge

The need for lightweight, low-maintenance, easily constructed bridges for remote locations has existed for a long time. The backcountry of forests and parks throughout the United States is made accessible by trail systems that often encounter streams, rivers, gorges, and other features that must be spanned. Because of their remote locations, conventional approaches to spanning these barriers often are impractical. The Eastern Federal Lands Highway Division of FHWA, in conjunction with the United States Forest Service and with assistance from E.T. Techtonics, designed, tested, and constructed a pedestrian trail bridge 13.9 m (45.5 ft) long made of fiber reinforced polymer (FRP) composite members. Development of design procedures for this type of bridge is presented. The initial load testing results used to evaluate the analysis and design of the structure are presented and future construction plans for this bridge are mentioned. Attractive characteristics of FRP composites for construction of pedestrian trail bridges and shortcomings are illustrated. Further testing and research of the Falls Creek Trail bridge are ongoing and further testing and research of FRP composites also are needed. Advances in the understanding of currently available materials, as well as advances in the materials themselves, likely will affect structural design methods and procedures in the future. However, on the basis of available data, FRP composites appear to be well suited to meeting the need for backcountry trail bridges.