Development of LRFD Specifications for Horizontally Curved Steel Girder Bridges (2006) / Chapter Skim
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A P P E N D I X A Literature Search
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A-iii C O N T E N T S A-iv List of Abbreviations and Symbols A-1 A1 Introduction A-1 A1.1 General A-1 A1.2 Objective A-1 A1.3 Research Procedure A-1 A1.4 Electronic Database A-1 A1.5 Synthesis A-1 A2 Overview of Literature Search A-1 A2.1 General A-2 A2.2 Analysis of Curved Bridges A-2 A2.3 Design A-3 A3 Curved I-Girder Bridges A-3 A3.1 Analysis A-3 A3.2 Design A-3 A3.2.1 Nominal Bending Strength A-5 A3.2.2 Curvature Effects on Elastic Lateral-Torsional Buckling A-5 A3.2.3 Cross-Frame Spacing and Lateral Bracing Effects A-5 A3.2.4 Local Buckling of Curved I-Girder Flanges A-5 A3.2.5 Strength of Curved I-Girder Web Panels under Pure Shear A-6 A3.2.6 Curved I-Girder Web Panels Subjected to Bending A-6 A3.2.7 I-Girder Webs Subjected to Combined Bending and Shear A-6 A3.2.8 Lifting of Slender Curved I-Girders A-6 A3.2.9 Constructibility Limit State A-6 A4 Curved Box-Girder Bridges A-6 A4.1 Analysis A-7 A4.2 Design A-7 A5 Conclusions and Recommendations for Further Study A-8 A5.1 Analysis Methods A-8 A5.2 I-Girders A-8 A5.3 Box-Girders A-8 A5.4 Constructibility A-8 A5.5 Extreme Event Limit State A-9 References A-13 Abstracts A-37 Background Research Pertaining to Updated AASHTO LRFD Specifications for Steel Structures, Third Edition
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A-iv L I S T O F A B B R E V I A T I O N S A N D S Y M B O L S a = distance between transverse stiffeners, b = width of flange, bf = width of compression flange, c = curvature parameter, C = shear strength constant, D = depth of the web panel, Dc = depth of the web panel in compression, fb = normal stress, Fb = allowable bending stress, fv = shear stress, Fv = allowable shear stress, Fy = minimum specified yield stress, fw = warping stress (flange lateral bending stress) , k = elastic shear buckling coefficient, L = length of girder, Mu = ultimate vertical bending moment, R = radius of curvature, Rd = reduction factor of shear due to initial out of flatness or reduction factor of deflection, as appropriate, Rs = reduction factor of stress, t = thickness of flange, tf = thickness of flange, tw = thickness of the web panel, Vp = plastic shear capacity, Vu = ultimate shear capacity, x = subtended angle between adjacent cross frames, y = critical moment ratio, = unbraced length of compression flange of I-girder, Ψ = reduction factor of local buckling of compression flange, and Ψw = parameter relating bend-buckling of curved I-girder web.
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Therefore, the literature collected and included in this report are those published after June 1993 and up to the time this search was conducted in early 2000. References made to articles in AASHTO LRFD Bridge Design Specifications and AASHTO Standard Specifications for Highway Bridges use the article numbers existing at the time of conducting the literature search.
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is the 1D line girder analysis method applied to horizontally curved box girder bridges. A variety of 2D planar grid analysis methods for horizontally curved bridges are available, including finite strip method, finite element method, and finite difference method.
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due to curvature in the McManus-Culver predictor equation in the Guide Specifications is doublecounted. Therefore, the lateral flange bending stress due to curvature at the critical cross-frame location must be set equal to zero.
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Guide Spec.
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(3) presented a regression formula for the cross-frame spacing resulting from a number of threedimensional finite element analyses of a large number of hypothetical curved bridges: where fw/fb = warping-to-bending stress ratio, L = girder span length in feet, R = radius of curvature in feet, and bf = compression flange width in inches.
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A3.2.9 Constructibility Limit State The past performance record of horizontally curved highway bridges has been excellent. Most problems associated with curved bridges occurred during construction.
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(9) is 152 pages long and includes essentially all major design procedures reflecting the provisions of the "Recommended Specifications for Steel Curved-Girder Bridges" (4)
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New analysis tools are available, including finite element computer programs that permit detailed analyses of both structural elements and entire structures. These analysis tools have not been adequately applied to horizontally curved girder bridges.
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. "Recommended specifications for steel curved-girder bridges." Appendix D of the final report submitted to National Cooperative Highway Research Program, Project 12-38, Transportation Research Board, National Research Council, Washington, D.C., December.
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. "Nominal bending and shear strength of horizontally curved steel I-girder bridges." Dissertation submitted to the Graduate Faculty of Auburn University in partial fulfillment of the requirements for the degree of Doctor of Philosophy.
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. "Some Considerations in the design and construction of horizontally curved highway bridges." Proceedings of the Fourth East Asia-Pacific Conference on Structural Engineering and Construction, p.
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ABSTRACT: The primary objective of NCHRP Project 12-38 was to develop revised Guide Specifications for Horizontally Curved Highway Bridges, based on current practice and technology, that could be recommended to AASHTO for possible adoption. The revised Guide Specifications were to be applicable to the design, fabrication, and erection of horizontally curved steel I-girder and box-girder bridges.
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INFO: Hanshin Expressway Public Corporation, October. ABSTRACT: This is the only semi-official design guide of horizontally curved girder bridges in the world today other than AASHTO Guide Specifications.
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A draft of the provisions has been submitted to AASHTO for consideration of adoption. An overview of the provisions is provided, including highlights of modifications to the existing AASHTO Guide Specifications for horizontally curved girders.
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2, Boston, MA, April 2–5. ABSTRACT: A research program focused on the development of improved design specifications for horizontally curved steel girder highway bridges has been underway for the past two years.
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Unfortunately, the results of these various research efforts are scattered and, in some cases, unevaluated. This paper complements and updates survey articles published in 1968 and 1978 and presents highlights of the analytical work conducted on horizontally curved steel I-girder bridges.
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However, unanswered questions remain concerning the fundamental behavior of horizontally curved steel girders that may not be adequately addressed in current design specifications. While there has been some isolated research, a coordinated large-scale effort to study curved girder behavior has not been undertaken in over 20 years.
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are presented. The test results for deformations and ultimate strength are found to be in good agreement with the corresponding values predicted by using the elasto-plastic finite element analysis.
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ABSTRACT: The currently used AASHTO Guide Specifications for Horizontally Curved Highway Bridges is primarily based on research per
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The Guide Specifications in its original form is disjointed and difficult to use. There is significant discontinuity in the compressive strength formulation between compact and noncompact sections, and the strength predicted by the formulations does not approach that predicted by the formulations for straight girders as the radius of the curved girder approaches infinity.
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6, June. ABSTRACT: Curved beam finite elements with shear deformation have required the use of reduced integration to provide improved results for thin beams and arches due to the presence of a spurious shear strain mode.
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Knowing the set of 18 exact shape functions their approximation is derived using the expansion of the trigonometric functions in the power series. Unlike the ones commonly used in the FEM analysis the functions suggested by the authors have the coefficients dependent on the geometrical and physical properties of the element.
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The results obtained from the present formulation are compared with those reported in the literature. The formulation presented here removes virtually all of the drawbacks present in existing GNL beam finite element formulations and has many additional benefits.
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This paper studies the linear, neutral, and nonlinear equilibrium of elastic horizontally curved I-beams under vertical loading, and develops a curved finite element model for their analysis. It is found that when the initial curvature of a curved beam is small, the primary coupling is also small and bending is the major action.
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10, May. ABSTRACT: A five-noded thirteen DOF horizontally curved beam element with or without an elastic base is presented.
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Much of the understanding gained from the CURT project is still reflected in the current Guide Specification for Horizontally Curved Highway Bridges. Additional experimental and analytical studies were performed in Japan during the 1980s to further advance the stateof-the-art understanding of curved girder behavior.
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A comparison of results using this regression equation with results from ultimate strength experimental testing of horizontally curved girders by others resulted in an unexpected excellent correlation. AUTHOR: Gendy, A
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ABSTRACT: The purpose of this paper is to investigate the dynamic behavior of horizontally curved I-girder bridges due to one or two trucks (side by side) moving across rough bridge decks.
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is applied to computation of the eigenvalues of small-amplitude free vibration for horizontally curved beams, including a warping contribution. Natural frequencies are calculated for single-span, curved, wide-flange uniform beams having a range of nondimensional parameters representing variations in warping stiffness, torsional stiffness, radius of curvature, included angle of the curve, polar mass moment of inertia, and various end conditions.
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6. ABSTRACT: This paper presents a method for determining the dynamic impact factor of horizontally curved steel box-girder bridges under vehicle loadings.The two-dimensional planar grid analogy is used to model box bridges.
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ABSTRACT: In 1992 the Federal Highway Administration (FHWA) , along with 13 states, began a project to study the behavior of horizontally curved steel bridges.
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ABSTRACT: Curvature greatly complicates the behavior of curved plate girders used in bridges. The outof-plane "bulging" displacement of the curved web results in an increase in stress, which must be considered in the design of plate girders with significant curvature.
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For straight girders, there is no advantage in using a compact compression flange with a noncompact web. For curved girders, however, the compact flange permits a larger lateral moment to be carried in combination with a given vertical moment.
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Presented in the paper are some of the major design considerations that are normally not considered in the straight bridge design. Likewise, erection of horizontally curved girders requires careful precautions that are normally extended in the erection of straight girders.
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The superior torsional stiffness of box girders, however, cannot be realized until the composite concrete deck has been hardened. For noncomposite dead loads, top flange diagonal bracing in horizontally curved girders acts as primary load carrying members.
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, 761–778. This paper summarizes the implementation and execution of a reasonably comprehensive set of finite element parametric Background Research Pertaining to Updated AASHTO LRFD Specifications for Steel Structures, Third Edition Prepared by Donald W
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As part of the Federal Highway Administration's curved steel bridge research project (CSBRP) , to further perform experimental and analytical study on the fundamental behavior of horizontally curved steel bridges, static load tests on a fullscale composite curved steel I-girder bridge were conducted.
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This study addresses the design and analysis of a full-scale horizontally curved composite test bridge selected to examine the system and component responses of a representative curved composite structure under all loading stages: non-composite dead load, composite service live load, and ultimate loading. The curved composite test bridge is designed at or above a number of maximum limits in AASHTO (2003 and 2004)
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. The findings from this and other research support the potential liberalization of the AASHTO strength design provisions for horizontally curved I-girder bridges.
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A total of 154 rolled and 123 welded I-section member LTB tests, and 11 rolled and 36 welded I-section member FLB tests, are considered.Reliability indices are estimated for Load and Resistance Factor Design (LRFD) of buildings based on the test statistics combined with established statistics for material and fabrication bias factors and the ASCE 7 load model.
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Several models that are well established in civil engineering practice as well as a number of other recently proposed models are considered.Since the model developed in Basler's seminal research is the method of choice in current American practice, the report focuses on the merits and limitations of the alternative models relative to Basler's. Statistical analyses are conducted on the predictions by the various models using an updated data set from 129 experimental shear tests, including 30 hybrid and 11 horizontally curved I-girders.
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Specifications, the AASHTO Guide Specifications for Curved Steel Bridge Design (2002) , and several additional references and analytical solutions of important note.
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As part of the Federal Highway Administration's curved steel bridge research project (CSBRP) , to further perform experimental and analytical study in the fundamental behavior of horizontally curved steel bridges, response of the superstructure of full-scale simple-span composite curved steel I-girder bridge during all phases of construction sequence was monitored.
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and a transverse stiffener spacing such that the ratio do/D was 3 for S1 and 1.5 for S1-S (producing do/R = 0.0575 and 0.0287)
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