Download or read book The Impact of the AASHTO LRFD Design Code on Bridge Stiffness and Strength written by Thomas Thaxton Baber and published by . This book was released on 2007 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Commonwealth of Virginia is currently transitioning from the long-used AASHTO Allowable Stress Design (ASD) specification to AASHTO's Load and Resistance Factor Design (LRFD) specification. The new specification features revised live loads, more conservative impact factors, a new load distribution method for analysis, and a probabilistically based limit state design approach. Traditional deflection limits have been made optional in the LRFD format. The extensive changes in the specification make it unclear as to whether bridges designed using the LRFD specification will be more or less flexible than those designed using the ASD specification. A series of bridges were designed using both ASD and LRFD formats to investigate what, if any, significant changes in bridge flexibility might be encountered and whether deflection limits are more or less likely to be violated with the LRFD format. Based upon the design of six single-span bridges with varying spans and numbers of girders, and a partial design of a three-span continuous bridge, it was concluded that the LRFD designs tend to be lighter and more economical in general and also tend to be more flexible than ASD designs of the same bridge. The weight savings appears to be more pronounced on single-span bridges than on multiple-span bridges because of the greater significance of local and lateral stability concerns in the finished bridges for multi-span bridges.

Download or read book AASHTO LRFD Impact Upon Bridge Stiffness and Strength written by David C. Simons and published by . This book was released on 2005 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book AASHTO Guide Specifications for LRFD Seismic Bridge Design written by and published by AASHTO. This book was released on 2009 with total page 249 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covers seismic design for typical bridge types and applies to non-critical and non-essential bridges. Approved as an alternate to the seismic provisions in the AASHTO LRFD Bridge Design Specifications. Differs from the current procedures in the LRFD Specifications in the use of displacement-based design procedures, instead of the traditional force-based "R-Factor" method. Includes detailed guidance and commentary on earthquake resisting elements and systems, global design strategies, demand modeling, capacity calculation, and liquefaction effects. Capacity design procedures underpin the Guide Specifications' methodology; includes prescriptive detailing for plastic hinging regions and design requirements for capacity protection of those elements that should not experience damage.

Download or read book AASHTO LRFD Bridge Design Specifications written by American Association of State Highway and Transportation Officials and published by . This book was released on 1994 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design of Highway Bridges written by Richard M. Barker and published by John Wiley & Sons. This book was released on 2013-02-04 with total page 1194 pages. Available in PDF, EPUB and Kindle. Book excerpt: Up-to-date coverage of bridge design and analysis revised to reflect the fifth edition of the AASHTO LRFD specifications Design of Highway Bridges, Third Edition offers detailed coverage of engineering basics for the design of short- and medium-span bridges. Revised to conform with the latest fifth edition of the American Association of State Highway and Transportation Officials (AASHTO) LRFD Bridge Design Specifications, it is an excellent engineering resource for both professionals and students. This updated edition has been reorganized throughout, spreading the material into twenty shorter, more focused chapters that make information even easier to find and navigate. It also features: Expanded coverage of computer modeling, calibration of service limit states, rigid method system analysis, and concrete shear Information on key bridge types, selection principles, and aesthetic issues Dozens of worked problems that allow techniques to be applied to real-world problems and design specifications A new color insert of bridge photographs, including examples of historical and aesthetic significance New coverage of the "green" aspects of recycled steel Selected references for further study From gaining a quick familiarity with the AASHTO LRFD specifications to seeking broader guidance on highway bridge design Design of Highway Bridges is the one-stop, ready reference that puts information at your fingertips, while also serving as an excellent study guide and reference for the U.S. Professional Engineering Examination.

Download or read book AASHTO LRFD Bridge Design Specifications written by American Association of State Highway and Transportation Officials and published by . This book was released on 1994 with total page 1134 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The provisions of these Specifications are intended for the design, evaluation and rehabilitation of both fixed and movable highway bridges. Mechanical, electrical, and special vehicular and pedestrian safety aspects of movable bridges, however, are not covered. Provisions are not included for bridges used solely for railway, rail transit or public utilities. For bridges not fully covered herein, the provisions of these Specifications mat be applied, as augmented with additional design criteria where required. These specifications are not intended to supplant proper training or the exercise of judgment by the Designer, and state only the minimum requirements necessary to provide for public safety. The Owner or the Designer may require the sophistication of design or the quality of materials and construction to be higher than the minimum requirements. The concept of safety through redundancy and ductility, and protection against scour and collision are emphasized. The design provisions of these Specifications employ the Load and Resistance Factor Design, LRFD, methodology. The factors have been developed from the theory of reliability based upon current statistical knowledge of loads and structural performance. Methods of analysis, other than those included in previous Specifications, and the modelling techniques inherent in them are included, and their use is encouraged. The commentary is not intended to provide a complete historical background concerning the development of these, or previous Specifications, nor is it intended to provide a detailed summary of the studies and research data reviewed in formulating the provisions of the Specification. However, references to some of the research data are provided for those who wish to study the background material in depth. The commentary directs attention to other documents that provide suggestions for carrying out the requirements and intent of these Specifications. However, those documents and this commentary are not intended to be a part of these Specifications."--Page1-1.

Download or read book Determine the Impact of the AASHTO LRFD Bridge Code and Transition the Department Into the Use of the AASHTO LRFD Design Code written by Andrzej S. Nowak and published by . This book was released on 2004 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: State departments of transportation (DOT's) are expected to use the new AASHTO LRFD bridge design code by 2007. There is a need for the review of the current Michigan bridge design practice and identification of differences between it and LRFD code. Therefore, the main objective of the project is the development of the training program for Michigan Department of Transportation (MDOT) technical staff and consultants. The tasks involved preparation of handout materials, presentations, and design examples. The training program was carried out in two series of five workshops. The workshops covered the following areas: loads and load distribution, slab design, prestressed concrete design, steel design, and design of abutments and piers.

Download or read book LRFD Guide Specifications for the Design of Pedestrian Bridges written by American Association of State Highway and Transportation Officials and published by AASHTO. This book was released on 2009 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Impact of AASHTO LRFD Specifications on the Design of Precast Pretensioned U beam Bridges written by Mohsin Adnan and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Texas Department of Transportation (TxDOT) is currently designing its highway bridge structures using the AASHTO Standard Specifications for Highway Bridges, and it is expected that TxDOT will make transition to the use of the AASHTO LRFD Bridge Design Specifications before 2007. The objectives of this portion of the study are to evaluate the current LRFD Specifications to assess the calibration of the code with respect to typical Texas U54 bridge girders, to perform a critical review of the major changes when transitioning to LRFD design, and to recommend guidelines to assist TxDOT in implementing the LRFD Specifications. This study focused only on the service and ultimate limit states and additional limit states were not evaluated. The available literature was reviewed to document the background research relevant to the development of the LRFD Specifications, such that it can aid in meeting the research objectives. Two detailed design examples, for Texas U54 beams using the LRFD and Standard Specifications, were developed as a reference for TxDOT bridge design engineers. A parametric study was conducted for Texas U54 beams to perform anin-depth analysis of the differences between designs using both specifications. Major parameters considered in the parametric study included span length, girder spacing, strand diameter and skew angle. Based on the parametric study supplemented by the literature review, several conclusions were drawn and recommendations were made. The most crucial design issues were significantly restrictive debonding percentages and the limitations of approximate method of load distribution. The current LRFD provisions of debonding percentage of 25 percent per section and 40 percent per row will pose serious restrictions on the design of Texas U54 bridges. This will limit the span capability for the designs incorporating normal strength concretes. Based on previous research and successful past practice by TxDOT, it was recommended that up to 75% of the strands may be debonded, if certain conditions are met. The provisions given in the LRFD Specifications for the approximate load distribution are subject to certain limitations of span length, edge distance parameter (de)and number of beams. If these limitations are violated, the actual load distribution should be determined by refined analysis methods. During the parametric study, several of these limitations were found to be restrictive for typical Texas U54 beam bridges. Two cases with span lengths of 140 ft. and 150 ft., and a 60 degree skew were investigated by grillage analysis method.

Download or read book LRFD Bridge Design written by Tim Huff and published by CRC Press. This book was released on 2022-02-23 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book examines and explains material from the 9th edition of the AASHTO LRFD Bridge Design Specifications, including deck and parapet design, load calculations, limit states and load combinations, concrete and steel I-girder design, bearing design, and more. With increased focus on earthquake resiliency, two separate chapters– one on conventional seismic design and the other on seismic isolation applied to bridges– will fully address this vital topic. The primary focus is on steel and concrete I-girder bridges, with regard to both superstructure and substructure design. Features: Includes several worked examples for a project bridge as well as actual bridges designed by the author Examines seismic design concepts and design details for bridges Presents the latest material based on the 9th edition of the LRFD Bridge Design Specifications Covers fatigue, strength, service, and extreme event limit states Includes numerous solved problems and exercises at the end of each chapter to illustrate the concepts presented LRFD Bridge Design: Fundamentals and Applications will serve as a useful text for graduate and upper-level undergraduate civil engineering students as well as practicing structural engineers.

Download or read book Application of the LRFD Bridge Design Specifications to High strength Structural Concrete written by S. H. Rizkalla and published by Transportation Research Board. This book was released on 2007 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explores recommended revisions to the American Association of State Highway and Transportation Officials' Load and Resistance Factor Design (LRFD) Bridge Design Specifications to extend the applicability of the flexural and compression design provisions for reinforced and prestressed concrete members to concrete strengths greater than 10 ksi.

Download or read book Simplified LRFD Bridge Design written by Jai B. Kim and published by CRC Press. This book was released on 2013-04-08 with total page 361 pages. Available in PDF, EPUB and Kindle. Book excerpt: Developed to comply with the fifth edition of the AASHTO LFRD Bridge Design Specifications [2010]––Simplified LRFD Bridge Design is "How To" use the Specifications book. Most engineering books utilize traditional deductive practices, beginning with in-depth theories and progressing to the application of theories. The inductive method in the book uses alternative approaches, literally teaching backwards. The book introduces topics by presenting specific design examples. Theories can be understood by students because they appear in the text only after specific design examples are presented, establishing the need to know theories. The emphasis of the book is on step-by-step design procedures of highway bridges by the LRFD method, and "How to Use" the AASHTO Specifications to solve design problems. Some of the design examples and practice problems covered include: Load combinations and load factors Strength limit states for superstructure design Design Live Load HL- 93 Un-factored and Factored Design Loads Fatigue Limit State and fatigue life; Service Limit State Number of design lanes Multiple presence factor of live load Dynamic load allowance Distribution of Live Loads per Lane Wind Loads, Earthquake Loads Plastic moment capacity of composite steel-concrete beam LRFR Load Rating Simplified LRFD Bridge Design is a study guide for engineers preparing for the PE examination as well as a classroom text for civil engineering students and a reference for practicing engineers. Eight design examples and three practice problems describe and introduce the use of articles, tables, and figures from the AASHTO LFRD Bridge Design Specifications. Whenever articles, tables, and figures in examples appear throughout the text, AASHTO LRFD specification numbers are also cited, so that users can cross-reference the material.

Download or read book AASHTO LRFD Bridge Design Guide Specifications for GFRP reinforced Concrete Bridge Decks and Traffic Railings written by and published by AASHTO. This book was released on 2009 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: Glass fiber reinforced polymer (GFRP) materials have emerged as an alternative material for producing reinforcing bars for concrete structures. GFRP reinforcing bars offer advantages over steel reinforcement due to their noncorrosive nature and nonconductive behavior. Due to other differences in the physical and mechanical behavior of GFRP materials as opposed to steel, unique guidance on the engineering and construction of concrete bridge decks reinforced with GFRP bars is needed. These guide specifications offer a description of the unique material properties of GFRP composite materials as well as provisions for the design and construction of concrete bridge decks and railings reinforced with GFRP reinforcing bars.

Download or read book Correlation of Shear Design Between AASHTO LRFD Bridge Design Specifications and AASHTO Guide Specifications for the LRFD Seismic Bridge Design written by David H. Sanders and published by . This book was released on 2017 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This report presents the analytical study of the shear capacity of reinforced concrete columns using both the AASHTO LRFD bridge design specifications and the AASHTO guide specifications for the LRFD seismic bridge design. The study investigates various levels of axial load, transverse reinforcement and longitudinal reinforcement to determine who the two specifications compare. The AASHTO guide specifications for the LRFD seismic bridge design permits the designer to use the AASHTO LRFD bridge design specifications or equations within the AASHTO guide specifications for the LRFD seismic bridge design with predetermined values. [...] A parametrical study was extended to conventional full-scale columns, using both the AASHTO LRFD bridge design specifications and the AASHTO guide specifications for the LRFD seismic bridge design to predict shear strength in order to analyze the direct effects of the parameters on the shear strength predictions."--Abstract

Download or read book AASHTO Load and Resistance Factor Design Movable Highway Bridge Design Specifications written by American Association of State Highway and Transportation Officials. Subcommittee on Bridges and Structures and published by AASHTO. This book was released on 2007 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Impact of AASHTO LRFD Bridge Design Specification Upon Bridge Live Loading in Maine written by Robert F. Lindyberg and published by . This book was released on 1997 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Application of LRFD Bridge Design Specifications to High strength Structural Concrete written by Neil Middleton Hawkins and published by Transportation Research Board. This book was released on 2007 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Research sponsored by the American Association of State Highway and Transportation Officials in cooperation with the Federal Highway Administration."