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This paper focuses on the conceptual use of a fiber-reinforced polymer (FRP) wind turbine blade that is repurposed for a second life as an electrical transmission pole. Thousands of tons o...

The objective of this research is to demonstrate that parts of decommissioned wind turbine blades can be repurposed for infrastructure applications for a sustainable future of the wind power industry. The purpose of this paper was to develop a methodology to conduct detailed structural engineering design of composite material parts extracted from wind turbine blades. A large section extracted from a 100-m long blade was repurposed as a roof for a small (approximately 40 m2) single-story masonry house. Geometric and material properties were taken from the blade design documents. A three-dimensional graphical model was created from the exterior surface and material layups. The roof was designed using the load and resistance factor design method familiar to civil engineers. Analysis of stresses and defections was conducted using hand calculations and the finite element method. The results of the analyses showed that the roof is within code mandated stress and deflection limits. The methodology developed could be applied to other wind blade repurposing concepts.

This paper describes the use of a system dynamics (SD) computational method to evaluate initial designs or upgrades of security measures to protect a building and its occupants from bioterr...

This paper presents a new type of discrete reinforcing element for concrete produced from either waste or new pultruded fiber-reinforced polymer (FRP) composite materials. These elements, r...

The purpose of this paper is to provide a review of and observations on progressive failure and ductility of fiber-reinforced polymer (FRP) composites of interest to civil and infrastructure construction applications. The primary reason for this is that although FRP composites have over the last 25 years successfully penetrated niche markets in civil engineering applications, one of the most frequently heard concerns from designers is their discomfort with the ductility of these composites and the structures built or reinforced with them, and that if the market for FRP applications in construction is to be expanded, the community must address this issue in greater depth. One approach is to use systemwide, structural, progressive failure behavior of the composite material itself to dissipate internal strain energy in lieu of the elastoplastic behavior of metallic materials. Specific applications of FRP composites in construction where progressive failure mechanisms have been considered are reviewed. These include FRP profiles, FRP frame connections, FRP reinforcing bars, externally bonded FRP or mechanically fastened FRP strengthening strips, and FRP column wraps. DOI: 10.1061/(ASCE)CC.1943-5614.0000355. © 2013 American Society of Civil Engineers. CE Database subject headings: Ductility; Energy dissipation; Progressive collapse; Pultrusion; Structure reinforcement; Composite materials; Construction. Author keywords: Crashworthiness; Ductility; Energy dissipation; Progressive failure; Pultruded profiles; Rebars; Strengthening; Wrapping.

Results of the behavior of pultruded fiber-reinforced polymer (FRP) I-shaped beams subjected to concentrated loads in the plane of the web are presented. Twenty beams with nominal depths from 152.4 to 304.8 mm were tested in three-point bending with a span-to-depth ratio of four. Load was applied to the top flange directly above the web—12 without bearing plates and 8 with bearing plates of varying width and thickness. All test specimens failed with a wedgelike shear failure at the upper web-flange junction. Finite-element results support experimental findings from strain gauge and digital image correlation data. Bearing plates increased beam capacity by 35% or more as a function of bearing plate width and thickness. Bearing plates increased average shear stress in the web at failure from 17.4 to 27.2 MPa—below the accepted value of in-plane shear strength (69 MPa). A design equation is presented, and predicted capacities are compared with experimental results. The average value of experimental capacity t...

Fiber-reinforced polymer (FRP) pultruded profiles are produced by a number of manufacturers worldwide in similar, but nonstandard, wide-flange, I, angle, and tubular profiles. At present there is no American National Standards Institute approved design code in the United States for structural design with pultruded FRP profiles. Manufacturers of pultruded profiles each provide their own design equations, design methods, material properties, and safety factors for their pultruded products. There is a need for standardization of production and design of pultruded profiles to enable mainstream use of these profiles in structural engineering practice. The purpose of this paper is twofold: (1) to provide appropriate resistance factors ( ϕ factors) for wide-flange pultruded columns that are compatible with ASCE 7 load factors and (2) to provide a unified analytical equation for local and global buckling of concentrically loaded axial members, which may be appropriate for a future design code. The resistance fact...

Due to the lack of data and experience with designing buildings for a bioterrorism hazard, it is important for civil engineering professionals to understand both the way that risk is currently accounted for in the design of a building for a bioterrorism hazard and the methods for analyzing risks to buildings that can be borrowed from risk analysis professionals. This paper provides a literature survey of four subject areas dealing with the risk analysis of bioterrorism applied to buildings: 1 perception of the risk of bioterrorism; 2 risk analysis of bioterrorism; 3 risk management of bioterrorism risks; and 4 risk communication of bioterrorism risks, and includes an example of a simple risk analysis process for a hypothetical building. Bioterrorism presents building design engineers with new chal- lenges. It is a very unpredictable hazard, and very little data exist to guide building designers and decision makers in protecting buildings from this hazard. Designing a building with bioterrorist attacks in mind involves many different disciplines, including, for example, structural, mechanical, and electrical engineering, architecture, landscape architecture, security design professions, and law enforcement. Large consequences are possible in the event of a successful attack, and many building design engineers have little or no experience with defending against a bioterrorist attack. It is important that a reasonable process for analyzing and dealing with these risks be established, and that the process include issues of risk perception and communication within the risk analysis framework.

Attaching reinforcing material such as steel or fiber reinforced polymer (FRP) plate to the external face of concrete members is a conventional technology used for strengthening concrete structures. Generally, three mechanisms are involved in the composite action between the concrete and the attachment: adhesion, dowel action, and friction. Methods have been developed for the identification of the interfacial bond properties when only one or two mechanisms exist at the interface. However, the existing methods cannot be used when all three mechanisms coexist. A methodology for testing the bond and the corresponding data interpretation procedure are proposed in this work to identify the bond properties of the interface involving all bonding mechanisms. As the bonding mechanisms are coupled and interact with each other, it is impossible to test all of them individually and separately. The proposed test protocol involves an analytical procedure that decouples individual mechanisms from the global response curves. Furthermore, conventional bond test methods involve extensive and labor-intensive strain gauging as well as complicated data regression analyses of test results in order to obtain the bond properties. The proposed method requires only the simplest instrumentation to measure displacement and load, without strain gauging. Test data processing also involves simple graphical interpretations only, without complicated and tedious mathematical data regression analyses. Therefore, the proposed method has advantages over the existing ones and can be easily adopted in engineering practice.

As buildings have become larger and house more people, political and societal issues have become more complex, and risks associated with occupying buildings have changed. In particular, since the terrorist attacks of 2001, the anxiety levels and perceived risks of building occupants especially occupants of tall, high-profile buildings have increased. These perceived risks include risks of terrorist attacks, natural disasters, the possibility of bomb threats, and catastrophic fires. The public's perception of risk is already incorporated into building design codes and performance-based design PBD methods for such hazards as earthquakes and fires—explicitly in some cases, implicitly in others. Risk perception will clearly need to be addressed in the design of buildings, as trade-offs in "acceptable" risk versus cost must be made. As terrorism represents a constantly changing design challenge, and is a target-specific hazard, as opposed to a location-specific hazard, it seems unlikely that prescriptive code requirements will be entirely effective at addressing this hazard. PBD codes are a promising approach for design issues that deal with such "cutting-edge" concepts.

This paper presents a case study of prefabricated double-layer pultruded fiber-reinforced polymer (FRP) grids for bridge deck construction. These grids were used to reinforce a 39.6 m long by 13.7 m wide (130 by 45 ft ) bridge deck on US Highway 151 over the De Neveu Creek in Wisconsin. The Federal Highway Administration Innovative Bridge Research and Construction Program invested resources in this program to investigate new uses for off-the-shelf technologies in constructing highway bridges. The feasibility of modifying manufacturing techniques to create innovative double-layer, 3D pultruded, FRP grids measuring 12.9 m long by 2.4 m wide by 16.5 cm deep ( 42 ft 6 in. by 8 ft by 6 1/2 in.) was investigated. In addition, the feasibility of placing the grids rapidly and constructing a bridge deck was also demonstrated. The FRP grids were required to meet a prescriptive material specification and a structural performance specification. Shear connectors were designed by the manufacturer to join large top and ...

The current method of bonding fiber-reinforced polymer (FRP) strengthening strips to concrete structures requires extensive time and semiskilled labor. An alternative method is to use a commercial off-the-shelf powder-actuated fastening system to attach FRP strips to concrete. A series of flexural tests were conducted on 15 304.8×304.8×3,657.6mm (12×12×144in.) reinforced concrete beams. Two beams were tested unstrengthened, 12 were strengthened with mechanically fastened FRP strips, and one was strengthened with a bonded FRP strip. The effects of three different strip moduli, different fastener lengths and layouts, and predrilling were examined. Three of the beams strengthened with mechanically attached FRP strips showed strengthening comparable to the beam strengthened with a bonded FRP strip. The same three beams strengthened with mechanically attached FRP strips also showed a greater ductility than the beam strengthened with a bonded FRP strip.

The Editorial Board of the American Society of Civil Engineers Journal of Composites for Construction~Lawrence C. Bank, Editor! sponsored a survey of the civil/structural engineering programs around the world on the subject of fiber reinforced polymer ~FRP! composites, excluding the traditional steel-concrete composite construction and fiber reinforced concrete. This paper summarizes the main results from the survey. During the last decade, considerable focus has been devoted to the use of FRP composites in construction. The main driving force is the need for revitalizing the aging infrastructure with innovative materials and structural systems that last longer and require less maintenance. As the construction industry embraces FRPs in the field, the need for educating civil engineers with background on the subject has become more evident. Despite a significant number of field applications and laboratory research, the survey shows that FRPs have not yet been fully implemented in the engineering curricula, and the classrooms are still lagging behind. To improve this situation, civil engineering and their extension programs must provide sufficient training on unique features of FRPs so that engineers could design or specify them in construction. This survey should be repeated as a gauging tool again at the end of this decade.

Five 609.5-mm deep fiber-reinforced polymer (FRP) beams with a span-to-depth ratio of 4∶1 were tested in three-point bending with the beam ends constrained to prevent global failure. A concentrated load was applied at midspan either directly to the top flange or through a 101.6 mm wide by 12.7-mm thick FRP bearing plate resting on the top flange. VIC-3D Digital Image Correlation Measurement Software from Correlated Solutions captured out-of-plane displacement of the webs, and Southwell plots were generated to determine buckling loads. Each specimen experienced a stability failure of the web before undergoing material failure in the upper web-flange junction. On average, web buckling occurred at 90% of the ultimate load. The introduction of a bearing plate did not significantly affect the buckling load or ultimate capacity of the specimens. One specimen was tested into the postbuckling range, unloaded, and reloaded to material failure and experienced no loss of strength or stiffness. Another specim...

In a recent research and development project a novel prototype pultruded composite structure was designed, fabricated, and tested. The bargelike, box-girder type structure measured approximately 24-ft long by 15-ft wide by 5-ft high (7.3 x 4.6 x 1.5 m). The structure was constructed from commercially available off-the-shelf pultruded structural profiles and panel sections. Tubular steel structural members and steel hardware were used to connect and join the different sections and subassemblies. The structure consisted of three 24-ft-long by 5-ft-wide by 5-ft-high (7.3 x 1.5 x 1.5 m) rectangular box-girder modular units and six 4-ft (1.2-m) wide modular deck panels. A design requirement was that the structure be capable of being transported by conventional, nonpermit trucking and be assembled at a remote site for subsequent testing. The structure was fabricated at a ship building and repair shop in Norfolk, Vir., whose primary expertise was with conventional steel ship-structure fabrication methods and which had no prior experience with fabricating a large pultruded structural system. To fabricate and assemble the structure, a set of construction documents was produced. These included a set of written construction and assembly specifications, a set of detailed construction drawings, a detailed parts list, and a schedule. This case study details the construction process and provides a step-by-step explanation of how the engineering design team developed the construction documents for a relatively complex pultruded composite structure. Details of the design, analysis, and testing of the system are provided elsewhere.

A numerical procedure for analyzing a common and catastrophic failure mode in pultruded composite material I-beams is presented in this paper. Pultruded wide-flange profiles (often referred to as I-beams) exhibit a number of different failure modes when loaded in flexure or axial compression. The particular failure mode of interest to this paper is that due to the local separation of the flange from the web of the profile following local buckling of the flange. A node-separation technique is used to simulate the progressive failure of the joint between the flange and the web of the wide-flange beam in the postbuckled regime. The procedure has beam implemented in NIKE3D, a multipurpose nonlinear implicit finite-element code. The fundamentals of the separation algorithm and the mechanics of the implementation in NIKE3D are described. The results of simulations using the proposed procedure are compared with experimental observations.

The bond properties of fiber reinforced polymer (FRP) reinforcing bars (rebars) at temperatures ranging from room temperature (20°C) to high temperatures of up to 250°C are discussed in this paper. The bond properties in this temperature range were studied for a number of commercially produced rebars, where different bond “treatments” were applied to FRP rebars. Test results showed a reduction of between 80 and 90% in the bond strength as the temperature increased from 20 to 250°C. In comparison, ordinary deformed steel rebars showed a reduction of only 38% in the same temperature range. In addition, a reduction in the bond stiffness, which was determined from the slope of the ascending branch of the pullout load versus slip curve, was seen as the temperature increased. At elevated temperatures the postpeak bond decrease was gradual as compared with the instantaneous drop at room temperature. Greater sensitivity to high temperatures was seen in FRP rebars, in which the bond relies mainly on the polymer treatment at the surface of the rod.

The response of a G4(1S) strong post steel w-beam guardrail system to pendulum impacts has been investigated in a series of full-size physical tests and in simulated experiments using the explicit finite-element analysis code DYNA3D. The physical tests were conducted at the Federal Outdoor Impact Laboratory at the Turner Fairbank Highway Research Center of the Federal Highway Administration in McLean, Va. In the pendulum tests, an 880-kg mass was used to strike the rail perpendicular to its face. The rail section was attached to steel posts and blockouts and supported in a specially designed fixture. Initial velocities of the pendulum at impact were 9.25, 20, 30, and 35 km/h. Acceleration, force, velocity, and displacement histories of the impact event were obtained from accelerometer data taken during the testing. Data from the DYNA3D simulations of the impact tests compared well with the data obtained from the full-scale testing. Displacement plots of the deformed shapes of the rails at 25-ms intervals compared favorably with high-speed film images. Force versus displacement histories showed good agreement with those obtained from quasi-static experiments. The use of pendulum impact tests for screening and evaluation of alternative guardrail systems is recommended.

This paper presents a quantitative economic analysis and a qualitative constructability analysis of three-dimensional fiber-reinforced plastic (FRP) reinforcement cages for concrete beams. Material, labor, and life-cycle costs are provided, and construction practice aspects are discussed. The results of the analyses indicate that prefabricated FRP cages can offer benefits to the construction industry. Although the initial costs of the FRP materials are likely to be higher than those of steel rebar, there is a significant potential for cost savings due to reduced maintenance and labor costs, as a result of the corrosion resistance of the FRP and the increased construction productivity. When direct life-cycle costs are considered, FRP reinforcements already constitute, in many cases, an economically competitive alternative to conventional steel reinforcement in adverse environments. If, in addition, the indirect cost savings as well as quality and safety issues are considered, the FRP reinforcement may be even more competitive.

Results of an experimental and analytical investigation of the behavior of a pultruded fiber‐reinforced plastic (FRF) portal frame subjected to short‐term static loads are presented. A 6 ft high by 9 ft wide (1.83m×2.74m) plane portal frame was designed and constructed of glass/vinylester pultruded FRP thin‐walled sections. Data obtained from short‐term load tests on the frame are presented. Failure of the beam‐to‐column connections and compression flange buckling of the girder are discussed. An analytical investigation was performed to predict the nonlinear response of the frame. The numerical model includes the effects of axial, shear, and flexural deformation of the pultruded numbers, flexibility of the beam‐to‐column connections, and the postbuckling of the frame girder. An expression for the nonlinear rotational stiffness of the pultruded beam‐to‐column connection is presented. The experimental data, obtained from the full‐size test, are compared with the analytical model.

The in‐plane shear modulus and the in‐plane shear strength of pultruded glass fiber reinforced plastic (FRP) materials were measured using the Iosipescu shear test method. Material specimens, in coupon form, were cut from the webs and flanges of commercially produced polyester and vinylester wide‐flange pultruded beams. The experimental testing procedure is described, and data reduction methods needed to define the shear modulus and the shear strength from the nonlinear stress‐strain curves are discussed. A new method to obtain the in‐plane shear modulus directly from load‐displacement data is proposed. Shear modulus predictions using the proposed method are compared with those obtained from the stress‐strain data.

The authors attempted to (1) present a so-called unified analytical equation for estimating the compressive strength of pultruded columns; (2) investigate the accuracy of their proposed equation by comparing analytical and experimental results; and (3) conduct Monte Carlo simulations of their selected unified equation to obtain a resistance factor for use in a load and resistance design-based format. The authors’ successful attempt to curve-fit experimental data with a mathematical function found in the literature falls short of providing a well-established and practical formulation that describes the behavior of axially compressed pultruded structural members. The discusser wishes to address the first two issues by providing background information on the unreferenced work that the authors used in their paper and to point out some typical pitfalls and frequent misconceptions contained in the authors’ article. The procedure for calculating the compressive strength of pultruded columns presented by the authors originated more than five decades ago with Ylinen (1956). Ylinen investigated the buckling strength of steel columns in the inelastic range, basing his analysis on the tangent modulus concept advocated by Engesser (1889; 1895a, b), where the average buckling stress is expressed in the form

As a cosponsor of the ASCE Journal of Composites for Construction, the International Institute for FRP in Construction (IIFC) has an official agreement with the Journal to publish occasional special issues. The Journal had its first IIFC-centric special issue in April 2007, and the present issue represents the second such edition. A proposal was made to ASCE that this IIFC-sponsored issue would be in honor of Professor Urs Meier, and this proposal was received with enthusiastic endorsement. It was felt that this would be timely and would constitute a fitting recognition in view of Professor Meier’s pioneering contributions to the field of fiberreinforced polymers (FRPs) in construction. It was also suggested that it would be most appropriate if there were a strong connection between the papers of the special issue and Professor Meier, either through working relationships between the authors or because the paper topics strongly relate to his work. To say that Urs Meier has enjoyed an illustrious professional career is a definite understatement. Urs Meier has held various positions at the Swiss Federal Laboratories for Materials Testing and Research (Empa), an institute that has approximately 800 coworkers and laboratory technicians in Dubendorf-Zurich, Switzerland. In 1983, Urs Meier rose to the rank of Deputy Director General of Empa, a position that he held until his recent retirement. In addition, he has also been lecturer and professor at the Swiss Federal Institute of Technology (ETH) in Zurich. Over the years, Urs Meier’s accomplishments in the application of FRPs in civil engineering have had a tremendous impact on the field; indeed, he has received many accolades and worldwide recognition for his pioneering work. Especially noteworthy is his work on the poststrengthening of civil structures with carbon-fiber-reinforced polymer (CFRP) strips, which has been successfully implemented at a growing rate worldwide, and the application of CFRP stay-and posttensioning cables. Urs Meier has been a prolific researcher and engineer with more than 250 publications to his credit. He has received numerous international best paper and technical innovation awards for excellence for his research and development contributions. He has also developed a number of worldwide recognized patents within the field. Other tributes to Urs Meier include the establishment by the ISIS Canada Research Network (Intelligent Sensing for Innovative Structures—an organization of the Canadian government) of a specially dedicated Urs Meier Scholarship and his being acclaimed Doctor of Engineering, honoris causa, by the Royal Military College of Canada in 2005. In preparing this special issue, a number of prospective authors from the international community were initially contacted by the guest editors. Each submission was then subjected to the usual rigorous review process of the Journal; this was handled by the Journal editor in chief, Professor Charles Bakis, according to the standard procedures. Ultimately, 11 papers emanating from Canada, Greece, Japan, Poland, Switzerland, the United Kingdom, and the United States were selected. We believe that these papers reflect the various topics that relate to Urs Meier’s contributions to the use of FRPs in civil engineering applications. They are an excellent representation of the depth and breadth of Urs Meier’s interests. We are delighted to present this special issue of the Journal of Composites for Construction to honor Professor Urs Meier for his remarkable achievements and exemplary dedication to this field. His accomplishments, leadership, and impact have been outstanding. This community has been extremely fortunate to benefit from both his technical and personal contributions. On behalf of all our colleagues, we offer our thanks and extend our very best wishes to this extraordinary researcher, teacher, engineer, and individual.