Download or read book A Study of the Deflections of a Curved Steel Girder Bridge written by Brian Joseph Rudie and published by . This book was released on 1997 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 National Research. This book was released on 2006 with total page 92 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 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 Heat curved Girders written by Marvin Henry Hilton and published by . This book was released on 1982 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present AASHTO bridge design specifications require that additional camber be built into steel girders that are to be heat curved. The additional camber is provided to allow for subsequent losses due to the dissipation of residual stresses imposed by the heat-curving process during fabrication of the girders. Many bridge engineers and steel fabricators, however, question whether the additional camber is necessary. To check the camber loss in a heat-curved girder bridge, a 140-ft., simply supported span was instrumented during construction of the bridge. The span was composed of four steel plate girders having radii of curvature varying from 802.51 ft. on the inside to 834.51 ft. on the outside of the alignment curvature. Girder deflection and camber loss were measured prior to and subsequent to the construction of the bridge deck. The AASHTO specifications for highway bridges indicate that losses of camber in heat-curved girders will occur both during construction of the bridge and subsequently under service loading. It is suggested that 50 of the camber loss will occur during construction and an additional 50% after the bridge has been subjected to several months of service loading. For the bridge investigated, some camber loss due to construction loading occurred shortly after placement of the concrete deck. The amount of loss, however, was only one-fourth of that determined from the AASHTO equation. In addition, there were no significant camber losses due to service loading over 6% months. The total loss under both construction and service loading was only 13% of that predicted by the AASHTO equation. Therefore, the results of the study suggest that the relationship given in the specifications for the calculation of the potential camber loss in a heat-curved girder is not applicable to girders having radii of curvature greater than 800 ft. The order of magnitude of the camber losses further suggests that the specifications may not be completely applicable to girders having radii of curvature less than 800 ft.
Download or read book Stresses in Steel Curved Girder Bridges written by Theodore V. Galambos and published by . This book was released on 1996 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt: Steel curved I-girder bridge systems may be more susceptible to instability during construction than bridges constructed of straight I-girders. The primary goal of this project is to study the behavior of the steel superstructure of curved steel I-girder bridge systems during all phases of construction, and to ascertain whether the linear elastic analysis software used by the Minnesota Department of Transportation (Mn/DOT) during the design process represents well the actual stresses in the bridge. Sixty vibrating wire strain gages were applied to a two-span, four-girder bridge, and the resulting stresses and deflections were compared to computational results for the full construction sequence of the bridge.
Download or read book Analytical Investigation of Curved Steel Girder Behaviour written by Michael Donald Simpson and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Horizontally curved bridges meet an increasing demand for complex highway geometries in congested urban areas. A popular type of curved bridge consists of steel I-girders interconnected by cross-frames and a composite concrete deck slab. Prior to hardening of the concrete deck each I-girder is susceptible to a lateral torsional buckling-type failure. Unlike a straight I-girder, a curved I-girder resists major components of stress resulting from strong axis bending, weak axis bending and warping. The combination of these stresses reduce the available strength of a curved girder versus that of an equivalent straight girder. Experiments demonstrating the ultimate strength characteristics of curved girders are few in number. Of the available experimental research, few studies have used full scale-tests and boundary conditions indicative of those found in an actual bridge structure. Unlike straight girders, curved girders are characterized by nonlinear out-of-plane deformations which, depending upon the magnitude of curvature, may occur at very low load levels. Because of the inherent nonlinear behaviour, some have questioned the application of the term lateral torsional buckling to curved girders; rather curved girders behave in a manner consistent with a deflection-amplification problem. Even with the advent of sophisticated analytical techniques, there is a glaring void in the documented literature regarding calibration of these techniques with known experimental curved girder behaviour. Presented here is an analytical study of the nonlinear modelling of curved steel girders and bridges. This is accomplished by incorporating large deflection and nonlinear material behaviour into three dimensional finite element models generated using the program ANSYS. Emphasis is placed on the calibration of the finite method with known experimental ultimate strength data. It is demonstrated that accurate predictions of load deformation and ultimate strength are attainable via the finite element method. The method is then extended to study the behaviour of a number of curved girders for which no experimental data exists. The influence of assumptions on the elastic stability behaviour of a curved beam is also examined by first formulating the total potential energy equation using a nonlinear strain definition. Then, the characteristic buckling equations are determined using the second variation of the total potential energy equation. Conclusion and recommendations are documented regarding the bifurcation and ultimate strength characteristics of curved girders. The finite element method is evaluated and as a tool for assessing curved girder and curved bridge behaviour.
Download or read book Engineering Research Series Research Report RR written by New York (State). Engineering Research and Development Bureau and published by . This book was released on 1975 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Influence Surface for Deflection of Curved Girder Bridges written by John Joseph Charland and published by . This book was released on 1970 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Construction Simulation of Curved Steel I Girder Bridges written by Ching-Jen Chang and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This study addresses the development of a prototype software system for analysis of horizontally curved steel I-girder bridges using open-section thin-walled beam theory. Recommendations are provided for the use of three-dimensional (3D) grid idealizations in analyzing curved I-girder bridge structural systems. The 3D grid idealizations account for the general displacements and rotations common within complex curved I-girder bridge structures, i.e., none of the displacement and rotational degrees-of-freedom are arbitrarily assumed to be equal to zero. Also, these idealizations account for the warping (or cross-bending) deformations of the I-girder flanges that dominate typical girder torsional responses. An approximate approach is investigated for capturing the influence of girder web distortion on composite I-girder responses. A key focus of this research is the development of prototype methods for simulating the construction of curved steel I-girder bridges, including erection of the steel and staged casting of the slab. The resulting capabilities allow engineers to evaluate the deflections, reactions and/or stresses at different stages of the steel erection or concrete slab construction, determine required crane capacities, tie-down, jacking or come-along forces, and calculate incremental displacements due to removal of temporary supports. Also, the capabilities can be used to determine the influence of different steel detailing methods on the bridge geometry, such as the web plumbness under the steel or total dead load. Key requirements necessary to ensure accuracy of the analysis results are addressed.
Download or read book A Study of Girder Deflections During Bridge Deck Construction written by Marvin Henry Hilton and published by . This book was released on 1971 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: Problems involved in obtaining the desired thickness of bridge decks were investigated. The study, which was limited to decks which were longitudinally screeded during construction, included (1) field measurements of the girder deflections during construction, and (2) a theoretical frame analysis of the girder deflections under the field loading conditions. Each of the two spans investigated were simply supported steel plate girder designs. When full span length longitudinal screeding is used, the finished grade elevations are set on the screeding edge of the machine, and remain independent of the bridge girder deflections during deck placement. Consequently, any factor affecting the girder deflections, and thus the forming elevations, will, in turn have bearing on the final thickness of a bridge deck. In addition, all factors which, in effect, cause the deck forming to be too high at the time the concrete is screeded to grade have the potential of causing a shy deck thickness. The most significant factors were found to be: (1) Plan dead load deflection values which are in error, (2) the differential temperatures existing between the top and bottom flanges of the girders during concrete placement as opposed to those that may have existed when the forming elevations were established, and (3) the transverse position of the concrete dead loading at the time a final screeding pass is made over a given point on a span. Based on the results of the study, certain recommendations are offered regarding the computation of dead load deflections and precautions to be observed during construction when longitudinal screeding of the concrete deck is used.
Download or read book Development of a Design Guideline for Phase Construction of Steel Girder Bridges written by Atorod Azizinamini and published by . This book was released on 2003 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Steel Bridge Erection Practices written by Fred R. Beckmann and published by Transportation Research Board. This book was released on 2005 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 345: Steel Bridge Erection Practices examines steel bridge erection practices for I-girder, tub-girder, and box-girder bridges; particularly curved, skewed, and staged structures. The report focuses on the impact of design and analysis practices on erection; methods used to predict erection deflections as a function of bridge type and complexity; shop-assembly practices and alternate methods of ensuring properly assembled geometry; stability issues; field connection practices; examples of structures in which erection practices have caused problems; owner requirements for erection procedures, implementation of requirements, and the impact of procedures on the quality of erection; and current and proposed research.
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 Proceedings of SECON 23 written by Moncef Nehdi and published by Springer Nature. This book was released on 2023-11-02 with total page 1053 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gathers peer-reviewed contributions presented at the 4th International Conference on Structural Engineering and Construction Management (SECON’23), held in Angamaly, Kerala, India, on 7-9 June 2023. The meeting served as a fertile platform for discussion, sharing sound knowledge and introducing novel ideas on issues related to sustainable construction and design for the future. The respective contributions address various aspects of numerical modeling and simulation in structural engineering, structural dynamics and earthquake engineering, advanced analysis and design of foundations, BIM, building energy management, and technical project management. Accordingly, the book offers a valuable, up-to-date tool and essential overview of the subject for scientists and practitioners alike, and will inspire further investigations and research.
Download or read book Concrete Dead Load Deflections of Continuous Steel Girder Composite Bridges written by Hani Melhem and published by . This book was released on 1996 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: The changes in the properties of a multi-span continuous steel girder composite bridge during construction can cause final dead load deflections that are quite different from the calculated theoretical values. The casting rate and the sequence of span casting affect the development of concrete stiffness which can significantly affect the final dead load deflections. The study involved two activities: collecting data from the testing of concrete cylinders and laboratory-size beams representative of composite bridge girders and developing a computer program that calculates dead load deflections during construction based on the data from the laboratory testing. The 300 concrete cylinders were tested at ages varying from 2 to 36 hours after pouring to establish stress-strain relations in axial compression. The four composite beams (20 ft (6.1 m) long) with 16 strain gages and 4 deflection gages were tested by applying small incremental loads starting soon after the concrete was poured. Based on these measurements, the change in stiffness of the composite beam was computed and the concrete properties evaluated. The test results helped obtain a relationship that describes the variation of the concrete Young's Modulus with time varying from 2 to 36 hours. Best results were obtained between 4 and 19 hours. The relationship established seems logical and appeared to be consistent in all tests. It was implemented in the computer program and is most valid for ages up to 10 hours. The additional concrete stiffness gained after 10 hours is based on the slope of the curve at 10 hours and a limitation factor that determines the characteristic length of the transition polynomial and which specifies how soon the curve should be asymptotic to the standard value of the 28-days modulus of elasticity. The computer program was verified, however, additional research is needed to test the program more rigorously, to study the effect of concrete confinement and the use of plasticizers, and to compare the results of additional test data with actual field measurements. The effect of the weight of construction equipment should also be studied. Excessive bridge deflection could be avoided with a better understanding of the factors and parameters that affect the deflection.
Download or read book Report No FHWA RD written by United States. Federal Highway Administration. Offices of Research and Development and published by . This book was released on 1979 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt:
