The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
John W. Fisher - One of the best experts on this subject based on the ideXlab platform.
-
LONG-TERM REMOTE MONITORING OF PROTOTYPE Orthotropic Deck PANELS ON THE BRONX WHITESTONE BRIDGE FOR FATIGUE EVALUATION
2020Co-Authors: Robert J Connor, S O Richards, John W. FisherAbstract:As part of a comprehensive fatigue evaluation of the replacement Orthotropic bridge Deck on the Bronx Whitestone Bridge in New York City, an in-depth field instrumentation, testing, and monitoring program has been developed and implemented on a 2-span prototype Orthotropic Deck panel located in the main suspended span. The data will be used to validate the lab fatigue testing program and establish in situ stress-range histograms at critical details. Controlled load testing was completed and uncontrolled remote monitoring is currently underway. The remote monitoring system utilizes an innovative application of traditional data acquisition coupled with recorded video to accurately establish the type, configuration, and position of trucks producing large stress ranges. This paper focuses on the unique approach to data acquisition and monitoring report, and briefly summarizes the initial results of the monitoring.
-
Full-scale fatigue tests of steel Orthotropic Deck panel for the Bronx – Whitestone Bridge rehabilitation
Bridge Structures, 2020Co-Authors: Paul A. Tsakopoulos, John W. FisherAbstract:A significant portion of the current rehabilitation of the Bronx – Whitestone Bridge includes replacement of the roadway Decking on the suspended span with closed-rib, steel Orthotropic Deck panels. Prior to the final design and production of the replacement panels, a full-scale laboratory fatigue test of a prototype panel was conducted at Lehigh University. The panel incorporated a diaphragm cutout and welded rib-to-diaphragm connection detail that was improved and refined with the aid of finite element models and experience gained from research conducted on Orthotropic Deck panels in the 1990s. Evaluations were made of the behavior and fatigue resistance of the Orthotropic Deck system and connections. Static and dynamic tests provided information on the two types of diaphragm plate splices and two types of bolted rib splices, determined the effectiveness of the rib wall stiffeners, and permitted a verification of a finite element model.
-
Evaluation of Cracking in the Rib-to-Deck Welds of the Bronx–Whitestone Bridge
Journal of Bridge Engineering, 2016Co-Authors: John W. Fisher, John M. BarsomAbstract:AbstractA new steel Orthotropic Deck was installed on the Bronx–Whitestone Bridge (BWB) between 2005 and 2006. In May 2007, longitudinal cracks were found by visual inspections underneath the Deck plate in the rib-to-Deck welds and have continued to occur. As of 2014, these rib-to-Deck weld cracks have required weld repair of approximately 305 m (1,000 ft) of the 65,374 m (214,480 ft) of rib welds in the new Orthotropic Deck. Detectable cracks have occurred randomly in 66 of the 408 shop-fabricated Deck panels. This paper’s focus is on modeling the crack propagation of the defective welds with fabrication-related hot cracks so that estimates of the possible cracking from these fabrication defects can be predicted. Creation of this model also involved considering truck traffic using the structure and the wheel paths along with the supporting ribs most likely to experience stress cycles during service.
-
Discussion of “Empirical Design Rules for Effective Utilization of Orthotropic Decks” by Roman Wolchuk
Journal of Bridge Engineering, 2015Co-Authors: John W. FisherAbstract:The author’s statement that there is no stress-strain proportionality of welded connections because there are residual stresses that are at the yield point at the weld toes or in the weld, and therefore that linear-elastic analysis is not applicable at such locations, is in error as worldwide research has shown in published experimental fatigue studies of welded steel details provided in detailed National Cooperative Highway Research Program (NCHRP) reports (Fisher et al. 1970, 1974; Keating and Fisher 1986) and several books (Fisher 1984; Barsom and Rolfe 2001; Maddox 1991; Fisher et al. 1998; Gurney 2006). These results are also incorporated into design specifications around the world (every edition of the AASHTO standards from 1974 to the current version (AASHTO 2002); every edition of the AASHTO LRFD bridge design specifications from 1994 to the current version (AASHTO 2012); every edition of the American Railway Engineering and Maintenance-of-Way Association (AREMA) specification from 1978 to the current version [AREMA 2014; British Standards Institution 1980; European Convention for Constructional Steelwork (ECCS) 1985; European Committee for Standardization (CEN) 2006; Japanese Society of Steel Construction 1993]). There is no cumulative plasticity at these welded details as the author implies in Fig. 3 of the paper; plasticity mostly occurs at gross section yielding. At the weld toe section, the residual stresses are in equilibrium on the cross section, and the surrounding material remains elastic under subsequent dead and live loads. The flowwithin the high tensile residual stress region at the weld toe is contained by the surrounding, primarily elastic, material, which prevents cumulative plasticity at these regions. This has been verified in the experimental and analytical studies cited previously. Accordingly, the nominal elastic stress in the gross section is used for fatigue design, without any explicit consideration for the local residual stresses, which are implicitly considered by experimentally obtained fatigue resistance curves. This approach to fatigue design has been accepted universally; the phenomenon of metal fatigue was formally acknowledged in the 1860s (Barsom and Rolfe 2001; Bannantine et al. 1990). Only loads that create yielding on the entire cross section, such as that which occurs in cyclic hysteresis loops (or gross section yielding), as applied in seismic loading, redistribute the residual stress states. This does not occur in the Orthotropic Deck, nor in other welded bridge elements,which are designed for nominal elastic stresses under service conditions. Measurements on full-scale Orthotropic Decks and other bridge members have verified this finding in the laboratory and in the field (Fisher 1984; Connor and Fisher 2000; Tsakopoulos and Fisher 2005a, b; Connor et al. 2003). These measurements have also verified the analytical evaluation of Orthotropic Decks (Fanjiang et al. 2004).
-
Measurements of a Steel Orthotropic Deck under Crawl Loading
Structures Congress 2011, 2011Co-Authors: R Alapati, Nirab Manandhar, John W. FisherAbstract:Recently a full scale prototype of a steel Orthotropic Deck was evaluated for a signature bridge in the ATLSS Engineering Research Center, Lehigh University. The Deck was innovatively designed to be integral with the existing Deck framing system. Since fatigue critical live load stresses at welded connections in an Orthotropic Deck can be produced by different loading dispositions, the response of the prototype Deck was determined under a rolling tandem axle bogie in eight transverse positions. Global displacements at the specimen boundary were simulated by three under Deck hydraulic actuators. The Deck was instrumented using more than 300 sensors at critical locations. A 3D finite element model of the prototype Deck was analyzed corresponding to the discrete axle positions and compared with experimental results. The prototype testing and the analytical studies provided critical understanding of the complex behavior of the Deck and the influence surface/response envelopes under local wheel loads.
Larry R Taylor - One of the best experts on this subject based on the ideXlab platform.
-
fatigue analysis and design of steel Orthotropic Deck for bronx whitestone bridge new york city
Transportation Research Record, 2004Co-Authors: Guangnan Fanjiang, Qi Ye, Omar N Fernandez, Larry R TaylorAbstract:A description is given of the parametric study done to evaluate the structural behavior of the replacement steel Orthotropic Deck planned for the Bronx—Whitestone Bridge in New York City. A principal objective was to analyze the Deck details for stress ranges that indicated sensitivity to fatigue cracking. On the basis of the analysis findings, important modifications were made to the preliminary Deck design. These changes were primarily to reduce the maximum stresses in the diaphragms and ribs around the diaphragm cutouts—locations that traditionally have been prone to cracking, as observed on Orthotropic Decks on other bridges. After the completion of the Deck design, a full-scale prototype Deck measuring 48 by 37 ft was fabricated and subjected to a series of laboratorycontrolled fatigue tests. Proper boundary conditions and loading procedures were created to produce stress ranges similar to those in the full bridge model. Laboratory test results correlated well with the computed stress ranges and demo...
Jim Weston - One of the best experts on this subject based on the ideXlab platform.
-
Trinidad Lake Asphalt Overlay Performance
2014Co-Authors: Keith W Anderson, Mark Russell, Jeffrey S Uhlmeyer, Dave Luhr, Bryan Dias, Jim WestonAbstract:Construction of the new Tacoma Narrows Bridge (TNB) included a steel Orthotropic bridge Deck. The higher flexibility of an Orthotropic Deck causes pavement placed upon it to fatigue and crack more quickly than pavement placed on a normal roadway. The hot mix asphalt (HMA) overlay placed on the new bridge incorporated Trinidad Lake Asphalt (TLA) to help resist the stresses of an Orthotropic Deck. The performance of the overlay after eight years of traffic was disappointing. Problems with the mix design, achieving specified densities, temperature differentials, and issues with the paver resulted in a pavement with a higher than desired void content. The result was severe rutting caused by raveling in the wheel paths possibly exacerbated by wear from studded tires. Cracking and delamination, the initial concern which prompted the use of the TLA modified HMA, were not a problem on the bridge Deck. As a result of the severe raveling, consideration is being given to the use of a conventional HMA when replacement of the Deck wearing surface becomes necessary.
-
Evaluation of Trinidad Lake Asphalt Overlay Performance
2008Co-Authors: Mark Russell, Jeffrey S Uhlmeyer, Keith W Anderson, Jim WestonAbstract:Construction of the new Tacoma Narrows Bridge (TNB) included a steel Orthotropic bridge Deck. The higher flexibility of an Orthotropic Deck causes pavement placed upon it to fatigue and crack more quickly than pavement placed on a normal roadway. The HMA overlay placed on the new bridge incorporated Trinidad Lake Asphalt (TLA) to help resist the stresses of an Orthotropic Deck. The basis of this report is to evaluate the short and long-term performance of the HMA overlay with TLA binder used on the TNB. This report provides background information on Orthotropic bridge Deck overlay construction practices and documents the construction of the overlay on the TNB. Annual summary reports over the next five years will document any changes in the performance of the overlay. A final report will summarize performance characteristics and future recommendations for use of this process.
Paul A. Tsakopoulos - One of the best experts on this subject based on the ideXlab platform.
-
Full-scale fatigue tests of steel Orthotropic Deck panel for the Bronx – Whitestone Bridge rehabilitation
Bridge Structures, 2020Co-Authors: Paul A. Tsakopoulos, John W. FisherAbstract:A significant portion of the current rehabilitation of the Bronx – Whitestone Bridge includes replacement of the roadway Decking on the suspended span with closed-rib, steel Orthotropic Deck panels. Prior to the final design and production of the replacement panels, a full-scale laboratory fatigue test of a prototype panel was conducted at Lehigh University. The panel incorporated a diaphragm cutout and welded rib-to-diaphragm connection detail that was improved and refined with the aid of finite element models and experience gained from research conducted on Orthotropic Deck panels in the 1990s. Evaluations were made of the behavior and fatigue resistance of the Orthotropic Deck system and connections. Static and dynamic tests provided information on the two types of diaphragm plate splices and two types of bolted rib splices, determined the effectiveness of the rib wall stiffeners, and permitted a verification of a finite element model.
-
full scale fatigue tests of steel Orthotropic Deck panel for the bronx whitestone bridge rehabilitation
Bridge Structures, 2005Co-Authors: Paul A. Tsakopoulos, John W. FisherAbstract:A significant portion of the current rehabilitation of the Bronx – Whitestone Bridge includes replacement of the roadway Decking on the suspended span with closed-rib, steel Orthotropic Deck panels. Prior to the final design and production of the replacement panels, a full-scale laboratory fatigue test of a prototype panel was conducted at Lehigh University. The panel incorporated a diaphragm cutout and welded rib-to-diaphragm connection detail that was improved and refined with the aid of finite element models and experience gained from research conducted on Orthotropic Deck panels in the 1990s. Evaluations were made of the behavior and fatigue resistance of the Orthotropic Deck system and connections. Static and dynamic tests provided information on the two types of diaphragm plate splices and two types of bolted rib splices, determined the effectiveness of the rib wall stiffeners, and permitted a verification of a finite element model.
-
Full-Scale Fatigue Tests of Steel Orthotropic Decks for the Williamsburg Bridge
Journal of Bridge Engineering, 2003Co-Authors: Paul A. Tsakopoulos, John W. FisherAbstract:Final design of the replacement Orthotropic Deck panels for the rehabilitation of the Williamsburg Bridge in New York City was based on laboratory fatigue tests of a full-scale prototype and an as-built Orthotropic Deck panel carried out at Lehigh University in the latter 1990s. The tests focused on determining and comparing the fatigue resistance of two different welded rib-to-diaphragm connection details that were recommended in the 1994 AASHTO LRFD Bridge Design Specifications and an alternative proposed by Steinman. The test on the prototype panel demonstrated that the fatigue resistance of the alternative detail was superior and influenced additional design changes that were incorporated into the replacement panels installed on the southern inner and outer roadways. Subsequent tests on the as-built panel further confirmed that the fatigue resistance of the alternative detail was superior and demonstrated that the additional design changes were also beneficial. Static and dynamic tests revealed the complex behavior of the Orthotropic Deck panels and demonstrated the effectiveness of retrofit and repair options at cracked connections. An assessment of fatigue resistance based on fracture mechanics models provided theoretical correlation. This research has led to the revision of design specifications for steel Orthotropic Decks first provided in the 2000 Interim AASHTO LRFD Specifications.
Guangnan Fanjiang - One of the best experts on this subject based on the ideXlab platform.
-
fatigue analysis and design of steel Orthotropic Deck for bronx whitestone bridge new york city
Transportation Research Record, 2004Co-Authors: Guangnan Fanjiang, Qi Ye, Omar N Fernandez, Larry R TaylorAbstract:A description is given of the parametric study done to evaluate the structural behavior of the replacement steel Orthotropic Deck planned for the Bronx—Whitestone Bridge in New York City. A principal objective was to analyze the Deck details for stress ranges that indicated sensitivity to fatigue cracking. On the basis of the analysis findings, important modifications were made to the preliminary Deck design. These changes were primarily to reduce the maximum stresses in the diaphragms and ribs around the diaphragm cutouts—locations that traditionally have been prone to cracking, as observed on Orthotropic Decks on other bridges. After the completion of the Deck design, a full-scale prototype Deck measuring 48 by 37 ft was fabricated and subjected to a series of laboratorycontrolled fatigue tests. Proper boundary conditions and loading procedures were created to produce stress ranges similar to those in the full bridge model. Laboratory test results correlated well with the computed stress ranges and demo...