2013 Session: 461

• Comparative Experimental Performance of Bridge Deck Slabs with AFRP and Steel Prestressed Precast Panels
  Abstract: Full-depth precast concrete panels expedite the construction process, enhance safety and quality control, and reduce the on-site labor requirements for bridge deck slab application. However, corrosion-induced deterioration of conventional steel during the lifetime of the structure is a serious concern affecting the durability and serviceability of the deck panels. Although replacing conventional steel with fiber reinforced polymer (FRP) bars has become more prevalent over the past few decades to overcome corrosion issues, there is still need for a comprehensive experimental study to investigate the structural performance of FRP concrete bridge deck slab with precast prestressed panels at full-scale and to address constructability issues as well. In this paper, a full-scale bridge deck slab consisting of full-depth precast panels reinforced and prestressed with aramid fiber reinforced polymer (AFRP) bars is experimentally investigated in terms of constructability and overall structural performance. Then it is compared to a similar system but reinforced with conventional steel and prestressing strand, deemed as the control specimen. The experimental results show the applicability of the proposed system having sufficient strength per AASHTO LRFD Bridge Design Specifications (2010) and considerable deformability when compared to the conventional system.
  Authors: Pirayeh Gar, Shobeir; Head, Monique Hite; Hurlebaus, Stefan; Mander, John
  Authors: Pirayeh Gar, Shobeir; Head, Monique Hite; Hurlebaus, Stefan; Mander, John
  Year: 2013
  Document Type: Paper
  Subject: Bridges and Other Structures; Design; Materials
  Session: 461
  Paper Number: 13-3207
• Externally Bonded GFRP and NSM Steel Bars for Enhanced Strengthening of Concrete T-beams
  Abstract: The technology of FRP strengthening has matured to a great extent. However, there is always room for performance improvements. In this study, external bonding of GFRP and near surface mounting of regular steel bars is combined to improve the behavior, delay the failure and enhance the economy of the strengthening. E-Glass FRP is selected due to its inexpensive cost and non-conductive properties to shield the NSM steel bars from corrosion. On the other hand, the use of NSM bars gives redundancy against vandalism and environmental deterioration of GFRP. An experimental program is conducted in which four T beams are designed and built. The first beam is tested as a control beam failing at about 15 kips. The second beam is strengthened using 5 layers of CFRP, which failed at 25.5 kips by CFRP debonding. The third beam is strengthened using two #5 steel NSM bars and 1 layer of GFRP, both extending to the support. This beam failed at 38.4 kips by GFRP and NSM debonding. The fourth beam is strengthened with the same system used for the third beam. However, the NSM steel bars were cut short covering only 30% of the shear-span while the GFRP was extended to the support. This beam failed at 25.9 kips by GFRP debonding and NSM delamination due to the lack of sufficient development of the NSM steel bars and the shear stress concentration at the steel bar cut off point. Nevertheless, the failure load developed was comparable to 5 layers of CFRP used for beam 2.
  Authors: Traplsi, Abdelbaset; Wuertz, Augustine; Rasheed, Hayder; AlKhrdaji, Tarek
  Authors: Traplsi, Abdelbaset; Wuertz, Augustine; Rasheed, Hayder; AlKhrdaji, Tarek
  Year: 2013
  Document Type: Paper
  Subject: Bridges and Other Structures; Design; Materials
  Session: 461
  Paper Number: 13-3120
• Experimental Evaluation of Connections in Hybrid FRP-Concrete Bridge Truss Girders
  Abstract: An innovative corrosion-free precast prestressed concrete truss girder has been developed for short- and medium-span slab-on-girder bridges. The girder consists of top and bottom concrete flanges connected by precast vertical and diagonal members made of fiber reinforced polymer (FRP) tubes filled with concrete. The verticals and diagonals are connected, respectively, to the concrete flanges by means of glass FRP dowels and stud reinforcement made of corrosion-resistant steel or FRP material. The flanges are pretentioned with carbon FRP tendons. The deck slab is reinforced with corrosion-resistant steel bars in the bottom transverse layer and with glass FRP bars in the bottom longitudinal and the top layers. The girders may be post-tensioned with external carbon FRP tendons to balance the slab weight and to provide continuity in multi-span bridges. The new system has the advantages of light weight and enhanced durability. The light weight reduces the initial cost and allows for longer spans. The improved durability reduces the maintenance cost and extends the structure’s life span. This paper describes the general details of the system and presents an experimental evaluation of its critical components, namely, the FRP tubes and the truss connections. Two types of FRP tube and four types of connection are investigated. Results of testing eight connection specimens under static loading and four specimens under fatigue are presented. The tests have shown excellent performance of the connection when filament wound tubes and continuous double-headed studs are used.
  Authors: El-Badry, Mamdouh; Schonknecht, Kyle; Abe, Hiroyuki
  Authors: El-Badry, Mamdouh; Schonknecht, Kyle; Abe, Hiroyuki
  Year: 2013
  Document Type: Paper
  Subject: Bridges and Other Structures; Design; Materials
  Session: 461
  Paper Number: 13-4134
• Flexural Behavior of Hybrid FRP-Ultra-High-Performance Fiber-Reinforced Concrete Composite Beams
  Abstract: This paper presents the development of a new composite beam consisting of a hybrid CFRP/GFRP I-beam and precast Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) slab. Hybrid FRP (HFRP) provides the advantage of high corrosion resistance while UHPFRC has high strength and durability. The combination of these two materials is expected to benefit structures subjected to severe environmental conditions and wherever there is a need for accelerated bridge construction. Three full-scale composite beams with varying UHPFRC slab width were tested under four point flexural loading. Bolt shear connectors with/without epoxy bonding were used in the tested beams. The bolt shear connectors and epoxy were used to resist the horizontal shear flow at the interface between the HFRP I-beam and the UHPFRC slab. The composite action between the HFRP I-beam and UHPFRC slab was investigated. The test results showed that all the composite beams exhibited significant improvements in stiffness and strength properties, above those of simple HFRP I-beam without UHPFRC slab. A fiber model was developed to predict the strength and stiffness of the tested beams and the model accuracy was verified. A fairly good agreement between the experimental and analytical results was found. High tensile strength of the CFRP in the HFRP tensile flange can be effectively utilized and delamination failure of the HFRP compressive flange can be prevented by addition of the UHPFRC slab on the top flange of the HFRP I-beam. The study revealed that HFRP-UHPFRC beams are efficient and can provide a very competitive, cost-effective and sustainable solution to bridge structures.
  Authors: Nguyen, Hai D.; Hiroshi, Mutsuyoshi; Zatar, Wael A.
  Authors: Nguyen, Hai D.; Hiroshi, Mutsuyoshi; Zatar, Wael A.
  Year: 2013
  Document Type: Paper
  Subject: Bridges and Other Structures; Design; Materials
  Session: 461
  Paper Number: 13-3699
• Comparative Experimental Performance of Bridge Deck Slabs with AFRP and Steel Prestressed Precast Panels
  Authors: Head, Monique
  Authors: Head, Monique
  Year: 2013
  Document Type: Presentation
  Subject: Bridges and Other Structures; Design; Materials
  Session: 461
  Paper Number: 13-3207
• Flexural Behavior of Hybrid FRP-Ultra-High-Performance Fiber-Reinforced Concrete Composite Beams
  Authors: Nguyen, Hai
  Authors: Nguyen, Hai
  Year: 2013
  Document Type: Presentation
  Subject: Bridges and Other Structures; Design; Materials
  Session: 461
  Paper Number: 13-3699
• Externally Bonded GFRP and NSM Steel Bars for Enhanced Strengthening of Concrete T-beams
  Authors: Wuertz, Augustine
  Authors: Wuertz, Augustine
  Year: 2013
  Document Type: Presentation
  Subject: Bridges and Other Structures; Design; Materials
  Session: 461
  Paper Number: 13-3120
• Experimental Evaluation of Connections in Hybrid FRP-Concrete Bridge Truss Girders
  Authors: El-Badry, Mamdouh
  Authors: El-Badry, Mamdouh
  Year: 2013
  Document Type: Presentation
  Subject: Bridges and Other Structures; Design; Materials
  Session: 461
  Paper Number: 13-4134
• Presiding Officer
  Authors: Sen, Rajan
  Authors: Sen, Rajan
  Year: 2013
  Document Type: Presentation
  Subject: Bridges and Other Structures; Design; Materials
  Session: 461
  Paper Number: Z13-461