Download or read book Evaluation of Internal Forces in Cross Frames of Multi stringer Steel Bridges written by Kwong Hui Kiew and published by . This book was released on 1990 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Internal Forces in Skewed Multi stringer Simply Supported Steel Bridges written by Nasser Daoud El-Ali and published by . This book was released on 1986 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cross Frames Analysis and Design written by Alfred G. Bishara and published by . This book was released on 1993 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Internal Forces in Medium Two Span Continuous Multi stringer Composite Skew Steel Bridges written by Dexian Guan and published by . This book was released on 1992 with total page 664 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spatial Interaction Between Cross Frames and Girders of Multi stringer Skewed Steel Bridges written by Wassef E. Elmir and published by . This book was released on 1988 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Internal Forces in Two Lane Three Medium Span Continuous Multi Stringer Composite Steel Skew Tangent Bridges written by Francisca Marini Karyadi and published by . This book was released on 1992 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sensitivity Analysis of Fatigue Evaluation of Steel Bridges written by Prem P. Rimal and published by . This book was released on 2001 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cross frame Stiffness Modification Factors for Composite Steel I girder Bridges written by Sunghyun Park and published by . This book was released on 2021 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: When analyzing steel I-girder bridges, the approach used to model cross-frames can significantly impact performance predictions for girder stability during construction and for cross-frame fatigue under in-service traffic loading. A common practice is to model cross-frame members as truss members subject to axial forces only. Recent research has shown that this approach can lead to erroneous predictions of cross-frame stiffness and cross-frame member forces. Actual cross-frames are typically constructed using single-angle members with gusset plate connections that introduce significant out-of-plane eccentricity and in-plane rotational restraint. These connection effects combined with the complex bending behavior of single-angles results in significant bending of the cross-frame members. This bending behavior can significantly change the axial stiffness of the cross-frame member and potentially introduce large errors in truss element models. The objective of this research is to study the behavior of cross-frames in steel I-girder bridges to better understand their stiffness and internal force distributions during in-service traffic loading on the completed bridge as well as during construction of the bridge. The research involves development of high-fidelity three-dimensional finite element models of steel I-girder bridge systems, with predicted cross-frame response validated using laboratory experimental data as well as data from field instrumentation of in-service bridges. The validated models are then used to conduct parametric finite element studies to examine a wide range of bridge and cross-frame geometries. Based on the results from the parametric studies, stiffness modification factor for truss element models is developed to improve the analysis of cross-frames in steel I-girder bridges
Download or read book Experimental and Analytical Evaluation of Cross frame Fatigue Behavior in Steel I girder Bridges written by Matthew Craig Reichenbach and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cross-frames are important structural components that serve many functions throughout the service life of steel I-girder bridge systems. They primarily act as stability braces to enhance the lateral-torsional buckling resistance of the girders during erection and deck construction, but also distribute live loads in the final composite condition. Under repetitive load cycles caused by heavy truck passages, cross-frames and their connections are susceptible to load-induced fatigue cracking if not properly designed. Cross-frames have historically been detailed and fabricated based on general rules-of-thumb and experience. In recent years, however, developments in bridge design specifications have necessitated the modernization of cross-frame design and analysis practices. Cross-frames are now designed and detailed based on rational analysis for all stages of construction and service life, which has further emphasized the importance of accurate and reliable analysis techniques and design criteria. Although considerable research over the past several decades has improved cross-frame design and analysis, the design industry has generally lacked quantitively based guidance on load-induced behavior of cross-frames in composite, in-service bridges. As such, this dissertation explores two major concepts: (i) the influence of skewed and curved superstructure geometry on the fatigue response of cross-frames and (ii) the limitations of simplified analysis techniques commonly utilized in commercial software programs with respect to estimating cross-frame force effects. Field experiments were performed on three steel I-girder bridges in the greater Houston area, and the stress ranges induced in key cross-frame members from truck traffic were monitored for one month each. Upon validating a finite-element approach with the measured data, an extensive analytical parametric study was conducted to expand the breadth and depth of knowledge gained from the limited field studies. In general, the load-induced fatigue behavior of conventional X- and K-type cross-frames were examined for a variety of bridge geometries commonly found in the United States. These analyses were performed with different levels of computational refinement, ranging from sophisticated three-dimensional approaches to simplified two-dimensional approaches. Based on the data collected and processed from the experimental and analytical studies, recommendations are proposed to improve the design and analysis of cross-frames in composite bridge structures. Because cross-frames represent a costly component of fabrication and erection, these recommendations ultimately lead to improved efficiency and economy of new steel bridge construction
Download or read book Improved Design Specifications for Horizontally Curved Steel Girder Highway Bridges written by Dann H. Hall and published by Transportation Research Board. This book was released on 1999 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Fatigue Design Load Models for Cross frames in Steel I girder Bridges written by Joshua Benjamin White and published by . This book was released on 2020 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt: There have been a number of advances in the level of understanding of cross-frame systems for steel I-girder bridges; however, very little work has focused on the proper loading conditions to produce an adequate estimate of the fatigue load in cross-frames. The goal of this research is to provide an improved definition of the fatigue loading for cross-frames in straight, horizontally-curved, and skewed steel I-girder bridges which will be analyzed using refined analysis techniques. In order to compare load effects, three bridges were instrumented and monitored. The bridges include: i) a straight bridge with normal supports, ii) a straight bridge with skewed supports, and iii) a horizontally curved bridge with radial supports. Data gathered from the field instrumentation was used to validate three-dimensional finite element analysis (FEA) models that were used to carry out extensive parametric analyses to improve the understanding of the behavior of cross-frame stresses as a function of truck position on the bridge. A wide range of geometrical parameters of straight and horizontally curved bridges were used to understand the general behavior of the bridges. The primary objectives of this research include the following: 1) Investigate the adequacy of the current AASHTO (American Association of State Highway and Transportation Officials) fatigue load model for the design of cross frames in steel I-girder bridges. 2) Investigate the effects of multiple presence on the design of cross-frames in steel I-girder bridges. 3) Investigate the reliability of the developed load model and identify the gaps in knowledge of cross-frame detail resistance data as it relates to the reliability of current design practices. These objectives were accomplished by examining recently collected, high-resolution, multi-lane weigh-in-motion (WIM) data, which represent actual truck traffic records in the US. The current AASHTO fatigue design load model was evaluated by comparing cross-frame load effects caused by the fatigue load model to load effects caused by simulated truck traffic representing actual live load. Influence surfaces generated from three-dimensional FEA models provided information on the stresses in select cross-frame members as a function on truck position on the bridge deck. WIM data representing real truck traffic (tens of millions of truck records) were filtered and analyzed; multi-lane data were analyzed using a cluster analysis. The statistical parameters of this WIM study were used to simulate actual live load on the three-dimensional bridge models and compare load effects to those generated by a fatigue design truck. The outcome of this study indicates the current fatigue design truck axle and weight configuration and placement of the fatigue design truck to maximize design-controlling fatigue effects for both the Fatigue I and Fatigue II AASHTO limit states is overly conservative. Stochastic techniques were used to investigate the implications of new load factors in the context of reliability-based fatigue design
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 Engineering for Structural Stability in Bridge Construction written by Federal Highway Federal Highway Administration and published by . This book was released on 2020-07-19 with total page 669 pages. Available in PDF, EPUB and Kindle. Book excerpt: This manual is intended to serve as a reference. It will provide technical information which will enable Manual users to perform the following activities:Describe typical erection practices for girder bridge superstructures and recognize critical construction stagesDiscuss typical practices for evaluating structural stability of girder bridge superstructures during early stages of erection and throughout bridge constructionExplain the basic concepts of stability and why it is important in bridge erection* Explain common techniques for performing advanced stability analysis along with their advantages and limitationsDescribe how differing construction sequences effect superstructure stabilityBe able to select appropriate loads, load combinations, and load factors for use in analyzing superstructure components during constructionBe able to analyze bridge members at various stages of erection* Develop erection plans that are safe and economical, and know what information is required and should be a part of those plansDescribe the differences between local, member and global (system) stability
Download or read book Advanced Methods of Structural Analysis written by Igor A. Karnovsky and published by Springer Nature. This book was released on 2021-03-16 with total page 824 pages. Available in PDF, EPUB and Kindle. Book excerpt: This revised and significantly expanded edition contains a rigorous examination of key concepts, new chapters and discussions within existing chapters, and added reference materials in the appendix, while retaining its classroom-tested approach to helping readers navigate through the deep ideas, vast collection of the fundamental methods of structural analysis. The authors show how to undertake the numerous analytical methods used in structural analysis by focusing on the principal concepts, detailed procedures and results, as well as taking into account the advantages and disadvantages of each method and sphere of their effective application. The end result is a guide to mastering the many intricacies of the range of methods of structural analysis. The book differentiates itself by focusing on extended analysis of beams, plane and spatial trusses, frames, arches, cables and combined structures; extensive application of influence lines for analysis of structures; simple and effective procedures for computation of deflections; introduction to plastic analysis, stability, and free and forced vibration analysis, as well as some special topics. Ten years ago, Professor Igor A. Karnovsky and Olga Lebed crafted a must-read book. Now fully updated, expanded, and titled Advanced Methods of Structural Analysis (Strength, Stability, Vibration), the book is ideal for instructors, civil and structural engineers, as well as researches and graduate and post graduate students with an interest in perfecting structural analysis.
Download or read book Timber Bridges written by Michael A. Ritter and published by Datamotion Publishing LLC. This book was released on 1990 with total page 916 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents a comprehensive analysis of the design, construction, inspection, and maintenance of timber bridges.
Download or read book Proposed Modification to AASHTO Cross frame Analysis and Design written by Matthew Craig Reichenbach and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cross-frames are important structural components that serve many functions throughout the service life of steel I-girder bridges. Under repetitive load cycles caused by heavy truck passages, cross-frames and their connections can be susceptible to load-induced fatigue cracking if not properly designed. The TRB National Cooperative Highway Research Program's NCHRP Research Report 962: Proposed Modification to AASHTO Cross-Frame Analysis and Design addresses knowledge gaps in an attempt to improve the reliability and economy of cross-frames in steel I-girder bridges and produces quantitatively based methodologies and design guidelines. Appendices B through F provide examples of cross-frame design for a straight bridge and a curved bridge as well as a comprehensive overview of the work completed in Phases I, II, and III of the project. Appendix A, Proposed Modifications to AASHTO LRFD, will be published by AASHTO.
Download or read book Fatigue and Fracture written by F. C. Campbell and published by ASM International. This book was released on 2012-01-01 with total page 699 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This book emphasizes the physical and practical aspects of fatigue and fracture. It covers mechanical properties of materials, differences between ductile and brittle fractures, fracture mechanics, the basics of fatigue, structural joints, high temperature failures, wear, environmentally-induced failures, and steps in the failure analysis process."--publishers website.
