爱魔域

A New Concept for Sustainable Refurbishment of Existing Bridges Using FRP Materials

Dr. Martijn Veltkamp

2017

This paper presents a new strengthening concept proposed for road bridges in the project SUREBridge (Sustainable Refurbishment of Existing Bridges), co-funded by the European Commission through the ERA-NET Plus Infravation 2014 Call. The project proposes an innovative and holistic refurbishment approach by using fiber-reinforced polymer (FRP) materials. The approach is designed for bridge upgrading, including repair and strengthening actions in the most effective and efficient way in terms of reducing construction time, resource consumption, and traffic disruption. SUREBridge concept consists of bonding prestressed carbon fiber reinforced polymer (CFRP) laminates to the tensile parts of flexural members (such as bottom flange of girders), and installing glass fiber reinforced polymer (GFRP) panels to the compressive parts (such as top of the existing concrete deck). A novel prestressing system is used to apply prestressed CFRP laminates eliminating the need for mechanical anchorage ...

downloadDownload free PDFView PDFchevron_right

The use of fibre-reinforced polymers (FRP) in bridges as a favourable solution for the environment

Artur Żyjewski

E3S Web of Conferences

The purpose of this article is to show the modern engineering, in which sustainability and taking care of ecology play a significant role. The authors are focused on FRP composite materials and their applications in civil engineering. Case studies showing renovation and design of new bridges with the use of FRP are presented and discussed to clarify benefits, which this solution provides. Main advantages of FRP materials in comparison with traditional ones, like concrete or steel are showed. The environmental impact of composites is described with respect to all life cycle of a product. Furthermore, some forms of waste management are covered. Last part of the paper refers to scientific description of the pedestrian bridge made of FRP, which was realized under the Fobridge research grant. The group of researchers headed by professor Chróścielewski from Gdansk University of Technology has developed a design solution of the pedestrian bridge manufactured in one production cycle. Moreover, the footbridge construction contains a significant share of a recyclable material commonly called PET. The article contains main characteristics of the structure and production process based on the resin infusion.

downloadDownload free PDFView PDFchevron_right

Upgrading of an Existing Concrete-Steel Bridge Using Fibre Reinforced Polymer Deck – A Feasibility Study

Robert Kliger

This paper examines the structural efficiency of fibre reinforced polymer (FRP) decks for replacing traditional concrete decks intended for bridge upgrading. The investigation, which is performed by means of finite element analysis, is demonstrated on an existing noncomposite concrete-steel bridge. The bridge had an inadequate structural capacity to bear the current traffic loads. Two alternative solutions are considered: replacing the old deteriorated concrete deck with a mechanically connected FRP (i.e. without composite action) and a solution where the deck acts compositely with the underlying steel girders. Different connection techniques between the girders and FRP deck are examined for both solutions. The finite element analysis is used to assess the overall structural behaviour of the bridge as well as the interfacial stresses between the FRP deck and the steel girders under different loading conditions. The results show that a significant stress reduction can be obtained by replacing the concrete deck with the lightweight FRP deck. This reduction is more pronounced if the deck is designed to work compositely with the existing steel girders.

downloadDownload free PDFView PDFchevron_right

Retrofit and Renovation of Concrete Bridges with Fibre Reinforced Polymer (FRP): The Third Alternative

Gerrit Visser

MATEC Web of Conferences

This paper presents Fibre Reinforced Polymer (FRP) as a third alternative construction material worth considering when retrofitting a bridge structure. FRP offers the following advantages: lighter than steel and concrete, non-corrosive, low in maintenance, stronger than structural steel and fatigue resistant. FRP has been used in Europe and more specifically in the Netherlands for almost 20 years in the retrofitting of road bridges, in new pedestrian bridges, road bridges and lock doors for sluices. The Netherlands has recently developed the updated Dutch Design Code CUR Recommendation 96, which was published in December 2017. The CUR Recommendation 96 will form the basis for developing the Eurocode FRP which is expected to be published between 2020 and 2025. The use of FRP in retrofitting of bridges is presented using examples which demonstrate how existing concrete decks, and steel and concrete substructures could be retained by the use of FRP in the retrofitting solution. Due to FRP being a relatively unknown material within the South African bridge design field, the authors have embarked on an awareness campaign targeting academics, government bodies, suppliers, manufacturers and contractors, with the aim of presenting FRP as a third alternative construction material in the South African bridge fraternity.

downloadDownload free PDFView PDFchevron_right

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

Makarand Hastak

Journal of Composites for Construction, 2004

Four different fiber-reinforced polymer ͑FRP͒ 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 characteristics͒ and unexpected responses are used to further quantify the performance of four FRP representative deck systems under identical traffic and environmental constraints.

downloadDownload free PDFView PDFchevron_right

Decision support in using fibre reinforced polymer (FRP) composites in rehabilitation of concrete bridge structures

Abe Nezamian

2004

This paper compares and reviews the recommendations and contents of the guide for the design and construction of externally bonded FRP systems for strengthening concrete structures reported by ACI committee 440 and technical report of Externally bonded FRP reinforcement for RC structures (FIB 14) in application of carbon fiber reinforced polymer (CFRP) composites in strengthening of an aging reinforced concrete headstock. The paper also discusses the background, limitations, strengthening for flexure and shear, and other related issues in use of FRP for strengthening of a typical reinforced concrete headstock structure such as durability, de-bonding, strengthening limits, fire and environmental conditions. A case study of strengthening of a bridge headstock using FRP composites is presented as a worked example in order to illustrate and compare the differences between these two design guidelines when used in conjunction with the philosophy of the Austroads (1992) bridge design code.

downloadDownload free PDFView PDFchevron_right

Fiber reinforced polymer composites for the superstructure of a short-span rural bridge

Jerome O'Connor

Composite Structures, 2002

Civil engineers have been seeking alternative materials to steel and concrete that may be less vulnerable to environmental damage. In addition, rising public concern about traffic delays experienced during the construction have increasingly influenced them to design bridges with materials and details that can be built rapidly. At the same time, life-cycle costs must be competitive with traditional materials because of the limited resources available to maintain the highway infrastructure. Fiber reinforced polymers (FRP) are one such alternative material. New York has recently began using and evaluating FRPs for bridge repair to strengthen deteriorated components, remove load postings, and prolong service life. This paper describes one such application, that allowed a bridge superstructure to be replaced in significantly less time than a conventional bridge project, in a cost-effective manner. The bridge design, fabrication, installation, proof-testing, and cost-benefit details are summarized.

downloadDownload free PDFView PDFchevron_right

Simulation study on construction process of FRP bridge deck panels

Makarand Hastak

Automation in Construction, 2007

In order to further enhance the application of fiber-reinforced composites in infrastructure renewal, it will be important to determine the productivity, man-hour requirements, and system bottlenecks that are important for understanding their construction process. Process modeling and simulation study were used to determine the productivity and cost per hour of installation in both FRP bridge deck panel and partial-depth precast concrete deck construction. The simulated results are applied to an example situation to compare two systems for rehabilitating bridge decks. Based on the simulation study, the productivity of FRP bridge deck panels is approximately four times higher than that of precast concrete decks. However, in comparison with the cost per hour including initial material cost of both systems, the cost per hour of partial-depth precast concrete decks is approximately four times cheaper than that of FRP bridge deck panels. The results show that the FRP bridge deck panels, as of now, are not cost-effective option for rehabilitating highway bridge decks unless it is expected to reduce the higher initial materials costs.

downloadDownload free PDFView PDFchevron_right

keyboard_arrow_downView more papers

Cited by

Reinforced concrete beams coated with fiberglass-reinforced polymeric profiles as partial substitutes for the transverse reinforcement

Augusto Wanderlind

Revista IBRACON de Estruturas e Materiais

abstract: The use of GFRP (Glass Fiber Reinforced Polymers) structural profiles in the construction sector is growing due to their attractive properties, such as high mechanical strength and durability in aggressive environments. With this, it is necessary to conduct studies that deepen the knowledge about the performance of these materials in structural applications. Therefore, this work aims to analyze the mechanical performance of reinforced concrete beams coated with GFRP profiles, in comparison to reinforced concrete beams, by analyzing groups with different spacing between transversal reinforcement. In all groups there was no change in the longitudinal reinforcement, and the D and Q groups were, respectively, made up of transverse reinforcement spaced twice and quadruple the one calculated for the reference beams, and presented the GFRP profiles in their constitution. All beams were tested at four-point bending, and strain gauges were installed in one of the beams of each grou...

downloadDownload free PDFView PDFchevron_right

Fiber Reinforced Polymer Culvert Bridges—A Feasibility Study from Structural and LCC Points of View

Jeffery Volz

Infrastructures

Soil–steel composite bridges (SSCB) have become increasingly popular for short-span bridges as an alternative to concrete slab bridges mainly due to their low initial cost, rapid manufacture, simplified construction, and geometrical adaptability. SSCBs have a variety of applications and can be used over waterways or roadways. While conventional bridges tend to lose their load-carrying capacity due to degradation, SSCBs gain strength because of backfill soil consolidation. However, the load carrying capacity and integrity of such structures highly depends on the condition and load-carrying capacity of the steel arch element. A major drawback of SSCBs, especially those located on waterways or with poor drainage, is corrosion and subsequent loss of cross-sectional capacity. Unfortunately, the inspection of such bridges is not straightforward and any damage/collapse will be very costly to repair/replace. Fiber reinforced polymer (FRP) composites offer an attractive alternative to replac...

downloadDownload free PDFView PDFchevron_right

Strength Degradation in Curved Fiber-reinforced Polymer (FRP) Bars Used as Concrete Reinforcement

Thanongsak Imjai

Polymers, 2020

Steel reinforcements in concrete tend to corrode and this process can lead to structural damage. Fiber-reinforced polymer (FRP) reinforcements represent a viable alternative for structures exposed to aggressive environments and have many possible applications where superior corrosion resistance properties are required. The use of FRP rebars as internal reinforcements for concrete, however, is limited to specific structural elements and does not yet extend to the whole structure. The reason for this relates to the limited availability of curved or shaped reinforcing FRP elements on the market, as well as their reduced structural performance. This article presents a state-of-the art review on the strength degradation of curved FRP composites, and also assesses the performance of existing predictive models for the bend capacity of FRP reinforcements. Previous research has shown that the mechanical performance of bent portions of FRP bars significantly reduces under a multiaxial combina...

downloadDownload free PDFView PDFchevron_right

Axial Behavior of FRP Confined Concrete Using Locally Available Low-Cost Wraps

Qasim Khan

Sustainability

This study investigates the influences of three types of locally available low-cost Fiber Reinforced Polymers (FRP) wraps and two concrete mix designs on the axial behavior of FRP confined concrete. The experimental program comprised four unconfined (control), four glass FRP Matt Strand (GFRP-MS) confined concrete, four glass FRP Rowing (GFRP-R) confined concrete and four carbon FRP (CFRP) confined concrete specimens with a diameter of 150 mm and a height of 300 mm tested under axial compression. The specimens were prepared using two normal strength concrete mix designs, i.e., Mix-A and Mix-B. The experimental results exhibited that an increase in the confined concrete strength per unit cost ratio of a single layer of GFRP-MS was about two times of a single layer of CFRP wrap, whereas the increase in confined concrete strength per unit cost ratio of single layer of GFRP-R was about four times of a single layer of CFRP wrap. GFRP-MS and GFRP-R wraps can exhibit similar confined stren...

downloadDownload free PDFView PDFchevron_right

Influence of SLS design requirements on the material consumption and self-weight of web-core sandwich panel FRP composite footbridges

Jordi Uyttersprot

Composite Structures, 2021

This paper reports a parametric study on the influence of the serviceability limit state design requirements on the material consumption and self-weight of web-core sandwich panel FRP composite footbridges. It describes the initial design process of a typical FRP web-core sandwich panel footbridge, focussing on the relevance of the various design checks on the overall material consumption at a given slenderness. It is clear that over a wide range of input parameters, only the SLS requirements are relevant for the design of this bridge type. Consequently, the final material consumption and achievable slenderness strongly depend on the code requirements. These requirements are non-uniform over various international codes, but are shown to have a huge influence on the material consumption. The final results heavily depend on the input value of the damping factor. In addition, human induced damping is not included in current design procedures, which may lead to a significant underestimation of the effective damping and consequently to over-design. The results contribute to understanding the mechanical behaviour of this promising bridge type, point to the relevance of the choice of SLS requirements in codes and to the lack of fully understanding the vibrational behaviour currently adopted in calculation models.

downloadDownload free PDFView PDFchevron_right

Measured dynamic properties of web-core sandwich panel FRP composite footbridges and their relation to pedestrian comfort analysis

Jordi Uyttersprot

Composite Structures, 2021

This paper reports experimental data for the dynamic properties (i.e. first fundamental flexural frequency, damping ratio, comfort class) of ten web-core sandwich panel FRP composite footbridges in Belgium, which contributes to the assessment of relevant input parameters for design and assessment of this promising bridge type, quickly gaining popularity in recent years. The data is gathered based on smartphone accelerometers, enabling easy, quick, affordable, and abundant measurements, while at the same time yielding reliable experimental values. Given the relatively short spans, the heel and excitation test methods are used, rather than the ambient vibration method. The tests indicate damping ratios of one to three percent, which are strongly dependent on the number of people on the bridge during the measurement. Additionally, comfort analysis tests with up to 58 people (0.5 P/m²) were conducted on five out of the ten bridges. The results indicate that the current design guidelines for pedestrian comfort analysis are overconservative and do not reflect the effect of pedestrian-induced damping, which is especially apparent for this bridge type given its very low modal mass and relatively low damping ratio.

downloadDownload free PDFView PDFchevron_right

Mechanical models for predicting the strength and stiffness of a beam-to-column adhesively-bonded connection between pultruded profiles

Francesco Ascione

Structures

This paper presents two simple analytical expressions to predict the strength and stiffness of an adhesive beamto-column connection between glass pultruded profiles (GFRP) subjected to shear and bending loads (vertical load applied at the free end of the beam). The joint configuration is characterized by a tubular column made of a commercially available hollow profile with a square cross section (90 mm × 90 mm × 8 mm) and two U-profiles (150 mm × 45 mm × 8 mm) arranged in the form of a built-up beam. The mechanical behaviour of this type of connection is governed by shear and bending stresses acting on the beam, with the latter becoming torsional stresses inside the adhesive layers and responsible for the failure of the connection. Regarding the strength prediction, a simple mechanical model based on the scheme of a single lap joint subjected to a traction force is presented. While, for the stiffness prediction, a simple formula for evaluating the adhesive layer deformability is proposed. With the latter, and by means of the Principle of the Virtual Power, the vertical displacement (corresponding to the vertical load applied) is evaluated and, consequently, the stiffness of the joint predicted. A comparison with the experimental results available in current literature has made it possible to verify the effectiveness of the proposed formulations which involve relatively few geometrical and mechanical parameters.

downloadDownload free PDFView PDFchevron_right

Time‐dependent properties of graphene nanoplatelets reinforced high‐density polyethylene

Liva Pupure

Journal of Applied Polymer Science, 2021

The deformation of polymers at constant applied stress is one of their major drawbacks, limiting their use in advanced applications. The study of this property using classical techniques requires extensive testing over long periods of time. It is well known that reinforced polymers show improved behavior over time compared to their neat counterparts. In this study, the effect of adding different amounts of graphene nanoplatelets (GNPs) on the time-dependent properties of high-density polyethylene (HDPE) is investigated using short-term creep tests and load/unload recovery tests. The results are discussed in terms of the test profile and the influence of loading history. Viscoplasticity/viscoelasticity analysis is performed using Zapas model and by comparing creep, creep compliance and pure viscoelasticity curves. The results show that the reinforcement of 15 wt% GNP have the most significant effect on the time-dependent behavior, reducing the strain by more than 50%. The creep compliance curves show that nano-reinforced HDPE behaves nonlinearly viscoelastically even at very low stresses. In addition to demonstrating the effect of nano-reinforcement, the discussion of the results concludes that the influence of loading history can be quite significant and should not be neglected in the design and evaluation of material behavior.

downloadDownload free PDFView PDFchevron_right

Identification of a Human-Structure Interaction Model on an Ultra-Lightweight FRP Footbridge

José M Goicolea

Applied Sciences, 2021

Due to the high strength-to-weight ratio of fibre reinforced polymers (FRPs), human-induced vibration problematic remains as a subject to be fully comprehended in order to extend the use of composites in Bridge Engineering. Thus, this paper studies an ultra-lightweight FRP footbridge, which presents excessive vertical vibrations when the fourth harmonic of a walking pedestrian is synchronised with the structure’s fundamental frequency. Focusing on the vertical bending mode, at 7.66 Hz, the bridge dynamic behaviour was assessed under the action of a single pedestrian crossing the facility at a step frequency of 1.9 Hz. As an over prediction of the footbridge response was computed using a moving force (MF) model available in a design guideline, a mass-spring-damper-actuator (MSDA) system was adopted to depict a walker. Hence, Human-Structure Interaction (HSI) phenomenon was considered. Employing the experimental results, parameters of the MSDA system were identified, leading to a HSI ...

downloadDownload free PDFView PDFchevron_right

keyboard_arrow_downView more papers