The Experts below are selected from a list of 22833 Experts worldwide ranked by ideXlab platform
Robert G Driver - One of the best experts on this subject based on the ideXlab platform.
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analysis of flange transverse bending of corrugated web i Girders under in plane loads
Journal of Structural Engineering-asce, 2007Co-Authors: Hassan H Abbas, Richard Sause, Robert G DriverAbstract:This paper presents theoretical, experimental, and finite-element analysis results for the linear elastic behavior of corrugated web steel I-Girders under in-plane loads. A typical corrugated web steel I-Girder consists of two steel flanges welded to a corrugated steel web. Previous research has shown that a corrugated web I-Girder under primary moment and shear cannot be analyzed using conventional beam theory alone, and a flange transverse bending analysis is required. A theoretical method, the fictitious load method, is presented herein as an analytical tool for quantifying flange transverse bending in corrugated web I-Girders. To validate this method, four-point bending experimental results for a large-scale corrugated web I-Girder are presented. The measured flange transverse displacements and flange stresses were in good agreement with the theoretical results especially in regions of constant shear. To gain additional insight, finite- element analysis results for the test Girder are presented, and compared to both the experimental and theoretical results.
Rola L Idriss - One of the best experts on this subject based on the ideXlab platform.
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in service shear and moment Girder distribution factors in simple span prestressed concrete Girder bridge measured with built in optical fiber sensor system
Transportation Research Record, 2010Co-Authors: Rola L Idriss, Zhiyong LiangAbstract:An optical fiber monitoring system was designed and built into the I-25 bridge at the Dona Ana exit in Las Cruces, New Mexico. The bridge is a simple-span, high-performance prestressed concrete Girder bridge. The Girders are six BT-63 high-performance-concrete Girders with a span length of 112.5 ft (34.2 m). Fiber Bragg grating optical fiber deformation sensors along with thermocouples were embedded in the Girders during fabrication. Sensors were installed along the top and bottom flanges and at midspan and quarter spans. Pairs of crossed sensors in a rosette configuration were embedded in the webs at the supports. The bridge was monitored for 2 years, from transfer of the prestressing force through service. The sensor data were analyzed to evaluate shear and moment Girder distribution factors, in situ material properties, prestress losses, camber, dynamic load allowance, and bridge performance under traffic loads. This study focuses on the lateral load distribution in the bridge. Shear and moment Girder distribution factors are obtained from a finite element model, sensor measurements under a live load test, as well as regular traffic loading and compared with the values specified by the AASHTO standard specifications (2002) and the AASHTO load and resistance factor design specifications (2007).
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live load distribution factors for prestressed concrete spread box Girder bridge
Journal of Bridge Engineering, 2006Co-Authors: Erin Hughs, Rola L IdrissAbstract:This study presents an evaluation of shear and moment live-load distribution factors for a new, prestressed concrete, spread box-Girder bridge. The shear and moment distribution factors were measured under a live-load test using embedded fiber-optic sensors and used to verify a finite element model. The model was then loaded with the American Association of State Highway and Transportation (AASHTO) design truck. The resulting maximum Girder distribution factors were compared to those calculated from both the AASHTO standard specifications and the AASHTO LRFD bridge design specifications. The LRFD specifications predictions of Girder distribution factors were accurate to conservative when compared to the finite element model for all distribution factors. The standard specifications predictions of Girder distribution factors ranged from highly unconservative to highly conservative when compared to the finite element model. For the study bridge, the LRFD specifications would result in a safe design, though exterior Girders would be overdesigned. The standard Specifications, however, would result in an unsafe design for interior Girders and overdesigned exterior Girders.
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multiplexed bragg grating optical fiber sensors for damage evaluation in highway bridges
Smart Materials and Structures, 1998Co-Authors: Rola L Idriss, M B Kodindouma, A D Kersey, Michael A DavisAbstract:A multiplexed Bragg grating optical fiber monitoring system is designed and integrated at the construction stage in an experimental full scale laboratory bridge. The test bridge is a 40 ft span non-composite steel Girder concrete deck bridge. The network of sensors is used to measure the strain throughout the bridge, with sensors bonded to the tension steel in the slab and attached to the bottom flange of the Girders. Resistive strain gages and Bragg grating sensors are placed side by side to compare results. The strain data are obtained for the pristine structure, then damage is introduced at midspan for an exterior Girder. Several levels of damage in the form of cuts in one of the Girders are imposed with the final cut resulting in a half depth fracture of the Girder. The load path in the structure is obtained using the built in sensor system.
Hiroshi Mutsuyoshi - One of the best experts on this subject based on the ideXlab platform.
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hybrid fiber reinforced polymer Girders topped with segmental precast concrete slabs for accelerated bridge construction
Transportation Research Record, 2014Co-Authors: Hai Nguyen, Wael Zatar, Hiroshi MutsuyoshiAbstract:The behavior of composite Girders made of hybrid fiber-reinforced polymer (HFRP) I-Girders, topped with precast ultra-high-performance, fiber-reinforced concrete (UHPFRC) slabs is presented in this paper. HFRP I-Girders were manufactured under the pultrusion process in which unidirectional carbon fibers and bidirectional fiberglass fabric or continuous strand mat were used. Four large-scale composite Girders were tested under four-point flexural loading. In the first composite Girder, the HFRP I-Girder was topped with a full-length precast UHPFRC slab. Twelve precast UHPFRC segments were used in each slab of the other three composite Girders. Either epoxy or mortar connections were used to connect the precast UHPFRC segments. The test results showed that the flexural stiffness of the composite Girder with the epoxy-connected segmental precast slabs was similar to that of the full-length precast composite Girder. The mortar-connected Girder exhibited more ductile behavior than the epoxy-connected Girder. A...
Herbert Gurtler - One of the best experts on this subject based on the ideXlab platform.
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composite action and adhesive bond between fiber reinforced polymer bridge decks and main Girders
Journal of Composites for Construction, 2005Co-Authors: Thomas Keller, Herbert GurtlerAbstract:This paper describes the behavior of hybrid Girders consisting of fiber-reinforced polymer (FRP) bridge decks adhesively connected to steel main Girders. Two large-scale Girders were experimentally investigated at the serviceability and ultimate limit state as well as at failure. One of the Girders was additionally fatigue loaded to 10 million cycles. Compared to the behavior of a reference steel Girder, deflections of the two Girders at the SLS were decreased by 30% and failure loads increased by 56% due to full composite action in the adhesive layer. A ductile failure mode occurred: Deck compression failure during yielding of the steel Girder. The adhesive connections were able to prevent buckling of the yielding top steel flanges. Thus, compared to the reference steel Girder, the maximum deflections at failure could be increased up to 130%. No deterioration due to fatigue loading was observed. Based on the experimental results, a conceptual design method for bonded FRP/steel Girders was developed. The proposed method is based on the well-established design method for hybrid Girders with concrete decks and shear stud connections. The necessary modifications are proposed.
Zhiyong Liang - One of the best experts on this subject based on the ideXlab platform.
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in service shear and moment Girder distribution factors in simple span prestressed concrete Girder bridge measured with built in optical fiber sensor system
Transportation Research Record, 2010Co-Authors: Rola L Idriss, Zhiyong LiangAbstract:An optical fiber monitoring system was designed and built into the I-25 bridge at the Dona Ana exit in Las Cruces, New Mexico. The bridge is a simple-span, high-performance prestressed concrete Girder bridge. The Girders are six BT-63 high-performance-concrete Girders with a span length of 112.5 ft (34.2 m). Fiber Bragg grating optical fiber deformation sensors along with thermocouples were embedded in the Girders during fabrication. Sensors were installed along the top and bottom flanges and at midspan and quarter spans. Pairs of crossed sensors in a rosette configuration were embedded in the webs at the supports. The bridge was monitored for 2 years, from transfer of the prestressing force through service. The sensor data were analyzed to evaluate shear and moment Girder distribution factors, in situ material properties, prestress losses, camber, dynamic load allowance, and bridge performance under traffic loads. This study focuses on the lateral load distribution in the bridge. Shear and moment Girder distribution factors are obtained from a finite element model, sensor measurements under a live load test, as well as regular traffic loading and compared with the values specified by the AASHTO standard specifications (2002) and the AASHTO load and resistance factor design specifications (2007).
