Analysis of Bridge Deck Panel Using Polyurethane Material

Composite Structures, 2008

The static behavior of an orthotropic bridge deck made of glass fiber reinforced polymer (GFRP) and polyurethane foam was investigated experimentally. The bridge deck consisted of GFRP unit modules with rectangular holes filled with foam to improve the structural behavior in the transverse direction. It was found that, although the elastic modulus of the foam compared to the homogenized modulus of the GFRP deck was about the order of 10 À3 , the structural behaviors in the transverse direction such as the nominal strength, stiffness, etc. were greatly improved when the GFRP bridge deck was filled with foam. Because of the low mass density of the foam used in this study, the bridge deck was still light enough while the structural properties were improved significantly. Webs of the foam-filled modules did not significantly contribute to strength development of the deck. However, propagation of a crack initiated in a module was caught by the webs so as to limit the crack to the inside of that cell only. This made the load-displacement behavior of the foam-filled GFRP deck less brittle. The longitudinal response of the GFRP deck was improved with the foam. The strength was increased about 20% but the elastic modulus was not improved.

Although still in their infancy, fiber-reinforced polymer (FRP) bridges have shown great promise in eliminating corrosion concerns and meeting (or exceeding) FHWA’s goal of 100-year life spans for bridges. While FRP bridges are cost-effective in terms of life cycle analyses, the combination of higher first costs and limited state DOT budgets has restricted their use. One area that has shown some headway is the use of FRP for bridge decks, focusing on the location where the majority of corrosion-related damage normally occurs. However, first costs still hamper widespread use of this approach. FRP bridge deck panels offer superior corrosion resistance, at one-fifth the weight of reinforced concrete. However, current FRP bridge deck panels typically rely on an intricate geometric honeycomb system between the top and bottom layers of the sandwich panel. This labor-intensive honeycomb construction more than doubles the cost of FRP panels compared to reinforced concrete. Although cost-eff...

The objective of this study is to replace complicated geometric honeycomb sandwich panels currently used for bridge decks by the proposed sandwich panel system. Replacing these panels would reduce not only initial production costs but also construction time. However, one of the challenges that most structural sandwich panels face is that the inner foam core has low stiffness and strength. Therefore, the proposed sandwich panel is being pursued to achieve higher structural performance. Three different polyurethane foam configurations were considered for the inner core, and the most suitable was recommended for further prototyping. These alternatives consisted of a high-density polyurethane foam (Type 1), a gridwork of thin, interconnecting, glass mat/resin webs that form a bidirectional gridwork that is in-filled with a low-density polyurethane foam (Type 2), and a trapezoidal-shaped, low-density polyurethane foam utilizing E-glass web layers (Type 3). The facings of the proposed san...

Composite structures have many useful applications in the field of aerospace, civil infrastructure and construction. Reinforced concrete has been used in most cases for manufacturing bridge decks, until today. Depending on the work carried out, defects can already occur after a few years. These defects mostly appear in the form of corrosion of steel reinforcement due to concrete's sensitivity to de-icing salts and water. To reduce maintenance costs, which are mainly caused by corrosion of the steel reinforcement, attempts were made to eliminate the steel reinforcement in the bridge deck. This can be achieved by replacing the whole concrete bridge deck with an FRP bridge deck. FRP bridge decks, besides the advantage of the absence of steel reinforcement, exhibit the advantage of low dead load (approx. 20% of a comparable concrete deck) combined with high strength. The present study provides an analytical method to determine the composite action of Trapezoidal FRP cell units, concrete and steel girder and the comparison of stress reduction/increase in Bridges when the concrete deck is replaced by an FRP deck and also the behavior of RCC and FRP deck under different loading conditions. Seismic analysis are also carried out using the finite element software ANSYS.

2013

Bridge decks composed of precast, prestressed panels (PCPs) overlain by cast-in-place (CIP) are popular in many states, including Texas. Optimization of top-mat reinforcement and reduction of collinear panel cracking were addressed in this project. Longitudinal top-mat reinforcement was found to be already optimized. Further optimization of transverse top-mat reinforcement is possible by slightly reducing the area of deformed reinforcement or by using welded-wire reinforcement. Collinear panel cracking can be reduced by reducing lowering the initial prestress or by placing additional transverse reinforcement at panel ends. Measured prestress losses in PCPs were at most 25 ksi, much less than the 45 ksi currently assumed by TxDOT. The comparative efficiency of different types of high-performance steel fibers was examined. Double-punch testing, appropriately standardized as proposed in this report, is a reliable and repeatable measure of the comparative efficiency of high-performance steel fibers.

This paper investigates the performance of polyurethane foam-infill bridge deck panels (PU sandwich panels) after being exposed to various environmental conditions. These panels were constructed with woven E-glass fiber/polyurethane facesheets that were separated by a trapezoidal-shaped, low-density polyurethane foam. Corrugated web layers were introduced into the core to enhance the panel's structural characteristics. The PU panels were manufactured through a one-step vacuum assisted resin transfer molding (VARTM) process. An experimental program was designed to simulate their in situ environments. The environmental conditions used included different conditioning regimens to examine the behavior of both GFRP laminates and PU sandwich panels. The GFRP laminates, which were made from the same materials as the PU sandwich panels, were exposed to ultraviolet radiation, a deicing solution at both room temperature and elevated temperature, and thermal cycling. The PU sandwich panels were exposed to thermal cycling (a series of freeze–thaw, mid–high temperatures, and mid– high relative humidity cycles). The thermal cycling exposure was conducted in a computer-controlled environmental chamber to duplicate seasonal effects in Midwestern states. Following the exposure regimens, tensile strength tests and four-point loading tests were performed on the GFRP laminates and the PU sandwich panels, respectively. The evaluation was based on visual inspection, strength, stiffness, and failure modes, as compared to those that were not conditioned (the control). The results of this study revealed that degradation did exist due to the effects of thermal cycling and the deicing solution. The ultraviolet radiation, however, did not cause any degradation. These results were within the recommended environmental durability design factors of the FHWA guidelines.

Construction and Building Materials, 2018

h i g h l i g h t s Novel ways of using polyurethane for structural and infrastructural applications have increased. The mechanical response of polyurethane can be described as hyper-viscoelastic. Polyurethane coatings provide enhanced environmental, chemical and physical resistance. High stiffness-to-weight ratio results broad structural composite application. Polyurethane spread through several substrate by creating matrix within the substrate.

2016

The contents of this report reflect the views of the authors who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views of the Wisconsin Department of Transportation or the Federal Highway Administration at the time of publication. This document is disseminated under the sponsorship of the Department of Transportation in the interest of information exchange. The United States Government assumes no liability for its contents or use thereof. This report does not constitute a standard, specification, or regulation.

Bridge Engineering Handbook, 1999

Reinforcing Fibers • Matrix Materials 51.3 Advantages and Disadvantages of Composites in Bridge Applications 51.4 Pultruded Composite Shapes and Composite Cables Pultruded Composite Shapes • Composite Cables 51.5 FRP Reinforcing Bars for Concrete 51.6 Composite Bridge Decks Advantages and Disadvantages • Composite Deck Systems • Truss-Type Deck System 51.7 Wearing Surface for a Composite Deck 51.8 Composite Bridge Structural Systems 51.9 Column Wrapping Using Composites 51.10 Strengthening of Bridge Girders Using CFRP Laminates 51.11 Composite Highway Light Poles 51.12 Nondestructive Evaluation of Composite Bridge Systems 51.13 Summary 51.1 Introduction Building a functional transportation infrastructure is a high priority for any nation. Equally important is maintaining and upgrading its integrity to keep pace with increasing usage, higher traffic loads, and new technologies. At present, in the United States a great number of bridges are considered structurally deficient, and many are restricted to lighter traffic loads and lower speeds. Such bridges need to be repaired or replaced. This task may be achieved by using the same or similar technologies and materials used originally for their initial construction many years ago. However, new materials and technologies may provide beneficial alternatives to traditional materials in upgrading existing bridges, and in the construction of new bridges. Composite materials offer unique properties that may justify their gradual introduction into bridge repair and construction.

2011

The Joint Transportation Research Program serves as a vehicle for INDOT collaboration with higher education institutions and industry in Indiana to facilitate innovation that results in continuous improvement in the planning, design, construction, operation, management and economic efficiency of the Indiana transportation infrastructure.