Download or read book Behavior Design and Construction of Horizontally Curved Composite Steel Box Girder Bridges microform written by Muayad Whyib Aldoori and published by Library and Archives Canada = Bibliothèque et Archives Canada. This book was released on 2004 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt: Horizontally curved girder bridges have been used considerably in recent years in highly congested urban areas. However, although significant research on physical testing and advanced analysis has been underway for the past decade, the practical employment of many recommendations has not been achieved by the engineering community nor have standards reflecting this work been brought into practice. The design process of curved composite bridges involves tracking the stresses and the potential failure change in the girders during erection, construction and service loading stages. For structural safety and serviceability, the designer estimates the stresses induced within the bridge and assure that they do not exceed the applicable specified limit state as required in bridge design standards. However, the designer may be concerned about the level of approximation that is used in his estimate or even the applicability of the underlying theory. To answer this question and provide the designer with more insight into the behavior of the curved bridges, the field testing during construction and service loading of a curved bridge located near Baltimore, Maryland is re-examined here using linear elastic three-dimensional finite element modeling. Comparisons are made between the finite element results and the measured results. Finally, to facilitate the finite element modeling effort for use by a designer, ANSYS Parametric Design Language (APDL) capabilities are used here to develop an analysis/design tool for "Bath-Tub" style curved steel girder bridges. This tool is then used to evaluate the effects of several important design variables on the response and behavior of the girders during the construction phase. This study demonstrates the ability of finite element modeling to assess the stiffness, serviceability performance, buckling behavior and ultimate strength of curved bridges during construction and it is a major step towards a performance based approach to design for stability. The level of safety or reliability that would be available during the erection and the construction processes of horizontally curved girder bridges represents another major concern for the designer. A three span continuous curved box girder bridge in Houston, Texas is used in this study as an example reflecting current detailing and fabricating practice and it is chosen for a detailed evaluation of the structural safety/reliability during the erection and construction process. This task involves simulating the girder erection and concrete slab placement sequence of the bridge using comprehensive nonlinear three dimensional finite element modeling.

Download or read book Development of Design Specifications and Commentary for Horizontally Curved Concrete Box girder Bridges written by Nutt, Redfield, and Valentine and published by Transportation Research Board. This book was released on 2008 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report provides specifications, commentary, and examples for the design of horizontally curved concrete box-girder highway bridges. The report details the development of the design procedures. Recommended Load and Resistance Factor Design (LRFD) specifications and design examples illustrating the application of the design methods and specifications are included in appendixes (available on the TRB website at http://trb.org/news/blurb_detail.asp?id=9596).

Download or read book Development of LRFD Specifications for Horizontally Curved Steel Girder Bridges written by J. M. Kulicki and published by Transportation Research Board. This book was released on 2006 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report contains the findings of research performed to develop design specifications for horizontally curved steel girder bridges.

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 Design Example Horizontally Curved Steel Box Girder Bridge written by Dann H. Hall and published by . This book was released on 1999 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design of Horizontally Curved Composite Box girder Bridges written by and published by . This book was released on 1995 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Because of their excellent torsional capacity, box girders are used extensively in modern bridge construction having curved alignments. Applications of most design codes have been limited to bridges where the radius of curvature is much greater than the span length and cross-sectional dimensions. To meet the practical requirements arising during the design process, simple design methods are needed for curved bridges. This paper presents the results of a parametric study on the relative behaviour of curved and straight box-girder bridges and on the development of a simplified design method for the combined longitudinal moment of curved bridges. The combined moment includes the effects of flexure, torsion, and distortion. Three simply supported concrete-steel composite bridge models, including single-cell, twin-cell, and three-cell box giders and subjected to loadings as specified in the Ontario Highway Bridge Design Code, were analyzed using the finite strip method. The parameters considered in the study include types of cross section: types, locations, and magnitudes of loads; span lengths; and radius of curvature. Preliminary analysis of the results suggests that the behaviour of horizontally curved box-girder bridges is dependent of a variety of parameters, but most importantly on the span-to-radius ratio. Empirical relationships for combined longitudinal moment between curved and straight box-girder bridges are also proposed.

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 Behavior and Design of Curved Composite Box Girder Bridges written by Sherif El-Tawil and published by . This book was released on 2002 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fatigue of Curved Steel Bridge Elements written by J. Hartley Daniels and published by . This book was released on 1980 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Module 5 Curved Steel Girder Bridges written by Gilbert Y. Grondin and published by . This book was released on 2019 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: DM5 is based on CSA Standard S6-14, Canadian Highway Bridge Design Code. Structural steel plates conform to CSA G40.21 grades 350A and 350AT.

Download or read book A Theoretical Investigation of the Dynamic Behavior of Horizontally Curved Steel Box Girder Bridges Under Truck Loadings written by Nicolas H. Galdos and published by . This book was released on 1988 with total page 680 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Horizontally Curved Steel Box Girder Bridge written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Behavior of Steel Tub Girders with Optimized Bracing Layouts written by Stalin Vinicio Armijos Moya and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Composite steel tub girders are a popular alternative for straight and horizontally curved bridges due to their high torsional stiffness and aesthetic appearance. While the closed girder in the finished bridge has a high torsional stiffness, prior to curing of the concrete deck the steel girder alone is relatively flexible. Consequently, steel tub girders require extensive amounts of bracing to avoid instability and cross section distortion due to the relatively low torsional stiffness during construction. The primary bracing systems include a top flange lateral truss as well as internal and external cross frames. The quasi-closed shape that results with the added bracing, results in a stiff girder system capable of resisting significant torsional moments and deformations. However, current design and detailing practices for steel tub girders commonly include several aspects that may lead to unnecessary fabrication costs and structural inefficiencies. The top flange lateral truss is commonly installed along the entire length of steel tub girders to increase the girder torsional stiffness. However, the horizontal truss is mainly effective near the ends of the girders where the shear deformations are the largest. Thus, partial top lateral bracing systems can be an alternative for straight and mildly horizontally curved bridge applications. Additionally, the internal K-frame braces are usually installed at every panel point to control cross-sectional distortion of the girders. However, the amount of internal K-frames can be significantly reduced with little impact on the structural performance. By optimizing the amount of bracing depending on the application, steel tub girders can be more cost-effective without undermining their structural integrity. In addition to modifications in the bracing, current AASHTO Specifications have several geometric restrictions for the section geometry of steel tub girders that may not be warranted. AASHTO restricts the web slope not to exceed the limit of 1 Horizontal to 4 Vertical. Tub girders with flatter web slopes can result in girders with higher tributary widths that could potentially reduce the number of girder lines on a bridge. In addition, top flanges are required to be centered on the top of the webs. If the top flanges are permitted to offset towards inside of the tub, more space would be available to connect directly the horizontal truss and avoid undesired eccentricities due to large gusset plates. Since these cross-sectional and bracing details are not currently allowed by AASHTO Specifications, a TxDOT-sponsored research project was performed to evaluate the impact of the aforementioned details using large-scale experimental tests and parametric finite element analyses. This dissertation evaluates the feasibility of optimized bracing layouts for straight and horizontally curved steel tub girders, in addition to analyzing the impact of modified cross-sectional geometries in the ultimate flexural capacity of steel tub girders

Download or read book Behavior of Steel Tub Girders with Modified Cross sectional Geometry written by Yang Wang (Ph. D.) and published by . This book was released on 2019 with total page 854 pages. Available in PDF, EPUB and Kindle. Book excerpt: Steel trapezoidal box girders, also referred to as steel tub girders, have been an attractive design option for long-span horizontally curved highway bridges. The completed composite bridge system presents an aesthetic appeal profile as well as large torsional stiffness. However, during construction, the open U-shaped steel girder section is relatively flexible in torsion and requires extensive bracing. A recent application on straight bridge system in Waco, Texas showed potential wider utilization of tub girders for span length normally reserved for precast concrete beams. Current design and fabrication practices have several relatively inefficient aspects regarding the section geometry and bracing details. These details include the restrictions on the slope ratio of the webs and the top flange-web attachment. Due to the use of empirical equation for live load distribution factor, the slopes of tub girder webs are restricted to be no greater than 1 Horizontal: 4 Vertical in current AASHTO specification. Significant economy can be achieved by utilizing flatter webs. While keeping the width of bottom flange constant, the use of flatter webs increases the tributary width of individual girder. This leads to potential reduction of the required number of girder lines to support traffic live loads and considerable savings on fabrication time and cost. Additionally, the webs of the tub girder are usually attached at the mid-width of the top flanges. This leaves limited flange width to connect the top lateral braces directly with the flange. Therefore, large gusset plates are frequently used to provide sufficient space for the connection. However, the use of gusset plates leads to poor load transfer and unnecessary fabrication cost. If the top flanges are allowed to offset toward the inside of the box, more flange width would be available for simple bolted bracing connection without using gusset plates. Since these proposed details are not currently permitted by AASHTO Specification, a TxDOT-sponsored research project has been conducted at UT Austin to demonstrate the impact of these improved tub girder details using large-scale experimental study and finite element analyses. This dissertation presents part of the results of this research project to provide better understanding of tub girder behavior as well as design recommendations to improve the efficiency and economy of the steel tub girder system

Download or read book The Development and Behavior of Vlasov Elements for the Modeling of Horizontally Curved Composite Box Girder Bridge Superstructures written by Yao T. Hsu and published by . This book was released on 1989 with total page 1014 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.

Download or read book Evaluation of Prefabricated Composite Steel Box Girder Systems for Rapid Bridge Construction written by Benjamin S. Pavlich and published by . This book was released on 2010 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: