Download or read book Cross frame Bracing of Steel Trapezoidal Box Girder Bridges with Skewed Supports written by Duane Milligan and published by . This book was released on 2002 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design Guidelines for Steel Trapezoidal Box Girder Systems written by and published by . This book was released on 2007 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cross frame Diaphragm Bracing of Steel Bridge Girders written by W. M. Kim Roddis and published by . This book was released on 2008 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: Steel plate girder bridges make use of traditional cross-frame diaphragms to stabilize the compression flange of girders. These braces are required during construction, especially during deck placement, to prevent lateral torsional buckling of bridge girders. Girder buckling capacity is a function of cross-frame diaphragm spacing as well as strength and stiffness. Recent developments in bridge design may cause the governing girder limit state to shift from one of strength to one of stability. These developments include the elimination of in-plan bracing, composite girders, High Performance Steels, and phased deck replacements. In addition, the American Association of State Highway and Transportation Officials (AASHTO) has changed its code requirement for cross-frame diaphragm spacing in the 1998 AASHTO LRFD Bridge Design Specifications. The requirement for 25-foot maximum brace spacing has been removed. The current requirement is for a "rational analysis" to determine cross-frame diaphragm spacing. Explanations of the problems these changes cause in design are discussed. A case study is presented of a bridge that suffered construction difficulties during deck placement. This investigation found that the cross-frame diaphragms were not stiff enough to brace the plate girders during the deck placement. Suggestions are given as to an efficient, economical design and spacing for cross-frame diaphragms on plate girder bridges.

Download or read book Cross frame and Diaphragm Behavior for Steel Bridges with Skewed Supports written by Todd Aaron Helwig and published by . This book was released on 2003 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Testing of a Trapezoidal Box Girder Bridge written by Michael Holowka and published by . This book was released on 1979 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Field Measurements of Diaphragm and Cross frame Stresses in Steel Box Girder Bridge with Skewed Support written by Sreekalyan Bobba Bobba and published by . This book was released on 2003 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Top lateral Bracing Systems for Trapezoidal Steel Box girder Bridges written by Brian S. Chen and published by . This book was released on 2003 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Composite Action During Construction of Steel Trapezoidal Box Girder Bridges written by and published by . This book was released on 2005 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: In steel trapezoidal box girder bridge systems, the U-shaped steel girder is designed to act compositely with the concrete deck to form a closed box for live loading. During the construction stage, however, the behavior is not well understood. The usual practice of assuming the system to be non-composite during construction requires substantial top flange bracing to form a quasi-closed box section. Composite box girders with live loading, and girders during construction, have to be evaluated during the design of curved steel trapezoidal box girder bridges. Considering both cases, the design for construction loading is the least understood and is the most important. Stresses due to construction loading can reach up to 60-70 percent of the total design stress for a given cross section. A three-phase study was undertaken to investigate the behavior of curved trapezoidal box girders during construction.

Download or read book Cross frame Forces in a Straight Bridge with Normal Supports written by Matthew Eric Moore and published by . This book was released on 2018 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cross-frame and diaphragm systems are important structural elements in steel I-girder bridges. These members enhance the lateral-torsional buckling resistance in straight girder systems by reducing the unbraced length. The critical stage for the braces from a stability perspective often occurs during construction of the concrete bridge deck when the non-composite steel girders must resist the entire construction load. The braces not only enhance the lateral-torsional buckling resistance of the girders, but are also necessary to resist the torsion applied to the girders due to the deck overhang construction, and distribute lateral loads across the structure from sources such as wind. In horizontally curved bridges, the braces are primary structural elements in the superstructure and engage the girders across the width of the bridge to behave as a structural system to resist the torsion that develops as a result of the curved geometry. For straight girder systems, the specifications of the American Association of State Highway and Transportation Officials (AASHTO) have generally provided little guidance in the sizing of the braces other than recommended connection plate (web stiffener) details or slenderness limits. While there have been many advances in recent years towards improving the understanding of the behavior of cross-frame systems, there has not been sufficient research carried out on the proper loading conditions for assessing the fatigue performance of cross-frames. The work outlined in this thesis is part of a larger study on the behavior of cross-frames in steel bridge system. The study is funded by the National Cooperative Highway Research Program (NCHRP 12-113). The fundamental goals of the research investigation are to produce methodologies and design guidelines for the following: evaluation of fatigue design stresses in cross-frames in straight and horizontally curved steel I-girder bridges; calculation of minimum cross-frame strength and stiffness requirements for stability bracing of I-girders during construction and in-service; development of improved methods to account for the influence of end connection details on cross-frame stiffness that extend beyond and improve upon the suggested guidance currently provided in Article C4.6.3.3.4 of the AASHTO LRFD Bridge Design Specifications. This work includes field monitoring and parametric FEA studies. The field studies are focused on three bridges: 1) a straight bridge with normal supports, 2) a straight bridge with skewed supports, and 3) a horizontally curved bridge. The field studies include rainflow monitoring of fatigue induced stresses in select cross-frames and the girders for a period of approximately 1 month as well as live load tests using trucks of known weights. This thesis focuses on some of the background studies, a survey of bridge owners around the United States, as well as the instrumentation and live load tests on the straight bridge with normal supports

Download or read book Guidelines for Analysis Methods and Construction Engineering of Curved and Skewed Steel Girder Bridges written by and published by Transportation Research Board. This book was released on 2012 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: "TRB's National Cooperative Highway Research Program (NCHRP) Report 725: Guidelines for Analysis Methods and Construction Engineering of Curved and Skewed Steel Girder Bridges offers guidance on the appropriate level of analysis needed to determine the constructability and constructed geometry of curved and skewed steel girder bridges. When appropriate in lieu of a 3D analysis, the guidelines also introduce improvements to 1D and 2D analyses that require little additional computational costs."--Publication information.

Download or read book Influence of Bracing Systems on the Behavior of Curved and Skewed Steel I girder Bridges During Construction written by Telmo Andres Sanchez and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The construction of horizontally curved bridges with skewed supports requires careful consideration. These types of bridges exhibit three-dimensional response characteristics that are not commonly seen in straight bridges with normal supports. As a result, engineers may face difficulties during the construction, when the components of the bridge do not fit together or the final geometry of the structure does not correspond to that intended by the designer. These complications can lead to problems that compromise the serviceability aspects of the bridge and in some cases, its structural integrity. : The three dimensional response that curved and skewed bridges exhibit is directly influenced by the bracing system used to configure the structure. In I-girder bridges, cross-frames are provided to integrate the structure, transforming the individual girders into a structural system that can support larger loads than when the girders work separately. In general, they facilitate the construction of the structure. However, they can also induce undesired collateral effects that can be a detriment to the performance of the system. These effects must be considered in the design of a curved and skewed bridge because, in some cases, they can modify substantially its response.

Download or read book Steel Box Girder Bridges written by and published by Thomas Telford Publishing. This book was released on 1973 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Behavior of Trapezoidal Box Girders with Skewed Supports written by Dawei Li and published by . This book was released on 2004 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cross frame and Diaphragm Behavior for Steel Bridges with Skewed Supports written by Todd Helwig and published by . This book was released on 2005 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cross frame and Diaphragm Behavior for Steel Bridges with Skewed Supports written by Liqun Wang and published by . This book was released on 2002 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Field Measurements on Lean on bracing System for Steel Girder Bridges with Skewed Supports written by Michelle L. Romage and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Introduction to Longitudinal Design of Post Tensioned Box Girders for Highway and Bridge Structures for Professional Engineers written by J. Paul Guyer, P.E., R.A. and published by Guyer Partners. This book was released on with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introductory technical guidance for civil engineers, structural engineers, highway engineers, bridge engineers and other professional engineers and construction managers interested in design and construction of box girder bridge structures. Here is what is discussed: 1. INTRODUCTION, 2. MODELING CONCEPTS, 3. STRENGTH LIMIT VERIFICATION—FLEXURE, 4. STRENGTH LIMIT VERIFICATION—SHEAR.