Skew composite bridges — analyses for ultimate load

1995 ◽  
Vol 22 (6) ◽  
pp. 1092-1103 ◽  
Author(s):  
Alaa Helba ◽  
John B. Kennedy
Keyword(s):  
Finite Element ◽  
Ultimate Load ◽  
Ultimate Limit State ◽  
Yield Line ◽  
Skew Bridges ◽  
Truck Loading ◽  
Composite Bridges ◽  
Composite Bridge ◽  
Bridge Models ◽  
Line Analysis

The ultimate limit state design for composite skew bridges with slab-on-I-steel girders requires a reliable prediction of their ultimate load capacity. In this paper, the results from a yield-line analysis of prototype composite bridges subjected to OHBDC truck loading are presented and compared with the results from a nonlinear finite element analysis of such prototype skew bridges. The favourable comparison between the two sets of results indicates that the collapse loads of skew composite bridges can be reliably and readily predicted by the yield-line method of analysis. Equations useful for the design and analysis of skew bridges are given. The experimental results from five composite bridge models tested to failure verify and substantiate the analyses. Results of the ultimate loads of six other skew composite bridge models with punched-to-failure deck slabs are also shown. A general and simplified method relating OHBDC truck loading to the collapse load predicted using the yield-line analysis is presented. Key words: analysis, bridges, composite, design, failure patterns, finite element, models, skew, yield-line.

Redistribution of longitudinal moments in straight, continuous concrete slab – steel girder composite bridges

2006 ◽  
Vol 33 (4) ◽  
pp. 471-488 ◽  
Author(s):  
A Ghani Razaqpur ◽  
Afshin Esfandiari
Keyword(s):  
Finite Element ◽  
Concrete Slab ◽  
Limit State ◽  
Slab Thickness ◽  
Ultimate Limit State ◽  
Bridge Design ◽  
Moment Redistribution ◽  
Composite Bridges ◽  
Composite Bridge ◽  
Aashto Lrfd

The effect of loading and geometric parameters on the transverse and longitudinal redistribution of moments in continuous composite bridges, comprising a concrete slab on parallel steel girders, is investigated with the nonlinear finite element method. Fifty bridges are analyzed over their entire range of loading up to failure, and their moment redistribution factors are determined and compared with the relevant predictions of the Canadian Highway Bridge Design Code (CHBDC) and the AASHTO LRFD Bridge Design Specifications. The parameters studied included truck position along the bridge, number of loaded lanes, bridge width, number of girders, slab thickness, degree of composite action, and presence of diaphragms. The study reveals that among the preceding parameters only the number of loaded lanes and the bridge width significantly affect transverse redistribution of moments at ultimate limit state (ULS). However, most of the preceding parameters affect longitudinal redistribution at ULS. Finally, it is demonstrated that plastic analysis of composite multi-girder continuous bridges, treated as an equivalent beam, provides a reasonable estimate of their longitudinal moment redistribution capacity at ULS. It is demonstrated that the actual load-carrying capacity of a composite bridge may be more than 50% higher than that predicted by the CHBDC or AASHTO code. Such higher predicted capacity may obviate the need for retrofit in some cases.Key words: analysis, bridge, composite, concrete, distribution, finite element, inelastic, load, steel.

Ultimate loads of orthotropic bridges continuous over isolated interior supports

1985 ◽  
Vol 12 (3) ◽  
pp. 547-558 ◽  
Author(s):  
John B. Kennedy ◽  
Ibrahim S. El-Sebakhy
Keyword(s):  
Prestressed Concrete ◽  
Structural Engineering ◽  
Ultimate Load ◽  
Test Results ◽  
Yield Line ◽  
Yield Line Theory ◽  
Truck Loading ◽  
Line Theory ◽  
Prestressed Concrete Bridge ◽  
Bridge Models

The collapse loads of orthotropic bridges continuous over isolated interior column supports are predicted by means of the yield-line theory. Equations for the collapse loads are derived for bridges of skew and rectangular planforms, and for an arbitrary angle of inclination of the line joining the centres of the interior columns. The analytical results are verified by experimental test results from prestressed concrete bridge models. Uniformly distributed and concentrated loads as well as Ontario Highway Bridge Design truck loading can be accommodated. A design example illustrating the use of the derived equations is presented. Key words: bridges (orthotropic), isolated supports, model tests, skew, structural engineering, ultimate load.

scholarly journals Development of innovative designs of bridge barrier system incorporating reinforcing steel or GFRP bars

2021 ◽  
Author(s):  
Hamidreza Khederzadeh
Keyword(s):  
Finite Element ◽  
Finite Element Modeling ◽  
Research Program ◽  
Ultimate Load ◽  
Phase Iii ◽  
Element Modeling ◽  
Yield Line ◽  
Gfrp Bars ◽  
Load Carrying ◽  
Actual Size

In harsh environment, corrosion of steel reinforcement causes durability problems. Glass Fiber Reinforced Polymer (GFRP) has emerged as an alternative to corrosion-related problem of steel bars in development of sustainable bridge deck and barrier walls. The current research program has been divided into five phases. In phase I, an extensive study has been conducted on pullout strength and bond behavior of pre-installed GFRP bars into concrete slabs and concrete cubes. In phase II, based on the Canadian Highway Bridge Design Code (CHBDC) factored applied moment at deck-wall junction, three configurations of GFRP-reinforced barrier detailing, using High-Modulus (HM) and Standard-Modulus (SM) GRFP bars, were proposed. The proposed barriers were tested by constructing five actual-size, 1.0-m long, PL-3 barrier models to determine their ultimate load carrying capacities and failure modes. In phase III, a full-scale PL-3 barrier made of GFRP-HM bars, with headed-end anchors as connecting bars to the deck slab, was constructed and tested under transverse static loading at both interior and exterior locations to-collapse to determine its crack pattern, failure mode and static ultimate load carrying capacity. In phase IV, from the trapezoidal failure pattern observed during testing the GFRP-reinforced PL-3 barriers, the research program was extended to revisit the triangular yield-line failure patterns in steel-reinforced PL-2 and PL-3 barriers specified in AASHTO-LRFD specifications. Experimental static tests to-collapse were conducted on constructed actual-size PL-2 and PL-3 steel-reinforced barriers, leading to more accurate expressions for their transverse load capacities developed based on the yield-line theory. In phase V, non-linear finite element analysis was conducted on GFRP-reinforced bridge barriers tested in phase III. The finite-element modeling was conducted to solely simulate the experimental test results for future research. A good agreement between experimental observations and numerical finite-element modeling was observed. Finally, this research led to (i) a more accurate design procedure for the GFRP - and steel-reinforced barrier wall and the barrier-deck joint, and (ii) design tables for the applied moment and tensile forces to be used to design the deck slab and the barrier deck-junction to resist transverse loading resulting from vehicle impact.

Finite element modelling and design of composite bridges with profiled steel sheeting

2016 ◽  
Vol 20 (9) ◽  
pp. 1406-1430 ◽  
Author(s):  
Ehab Ellobody
Keyword(s):  
Finite Element ◽  
Boundary Conditions ◽  
Finite Element Model ◽  
Failure Modes ◽  
Element Model ◽  
Finite Element Models ◽  
Test Results ◽  
Composite Bridges ◽  
European Code ◽  
Composite Bridge

This article discusses the non-linear analysis and design of highway composite bridges with profiled steel sheeting. A three-dimensional finite element model has been developed for the composite bridges, which accounted for the bridge geometries, material non-linearities of the bridge components, bridge boundary conditions, shear connection, interactions among bridge components and bridge bracing systems. The simply supported composite bridge has a span of 48 m, a width of 13 m and a depth of 2.3 m. The bridge components were designed following the European code for steel–concrete composite bridges. The live load acting on the bridge was load model 1, which represents the static and dynamic effects of vertical loading due to normal road traffic as specified in the European code. The finite element model of the composite bridge was developed depending on additional finite element models, developed by the author, and validated against tests reported in the literature on full-scale composite bridges and composite bridge components. The tests had different geometries, different boundary conditions, different loading conditions and different failure modes. Failure loads, load–mid-span deflection relationships, load–end slip relationships, failure modes, stress contours of the composite bridge as well as of the modelled tests were predicted from the finite element analysis and compared well against test results. The comparison with test results has shown that the finite element models can be effectively used to provide more accurate analyses and better understanding for the behaviour and design of composite bridges with profiled steel sheeting. A parametric study was conducted on the composite bridge highlighting the effects of the change in structural steel strength and concrete strength on the behaviour and design of the composite bridge. This study has shown that the design rules specified in the European code are accurate and conservative for the design of highway steel–concrete composite bridges.

Shear distribution in simply supported skew composite bridges

1995 ◽  
Vol 22 (6) ◽  
pp. 1143-1154 ◽  
Author(s):  
Tarek Ebeido ◽  
John B. Kennedy
Keyword(s):  
Parametric Study ◽  
Load Distribution ◽  
Experimental Program ◽  
Distribution Factor ◽  
Simply Supported ◽  
Shear Distribution ◽  
Truck Loading ◽  
Composite Bridges ◽  
Bridge Models ◽  
Composite Steel

Composite steel–concrete bridges remain one of the most common types built. Proper design of new bridges and evaluation of existing bridges requires accurate prediction of their structural response to truck loads. The American Association of State Highway and Transportation Officials has traditionally applied a load distribution factor for both moment and shear. The Ontario Highway Bridge Design Code (OHBDC) considers several parameters in establishing load distribution factors for moment. However, the method is limited to bridges with skew parameters less than a certain value specified in the code. The presence of skew reduces the longitudinal moments in the girders. However, it also causes high concentration of shear in the girder closest to the obtuse corner and reduces shear concentration in the girder closest to the acute corner as well as in the interior girders. Therefore, shear should be considered in the design of such bridges. In this paper, the influence of skew on the shear distribution factor is investigated. The influences of other factors such as girder spacing, bridge aspect ratio, number of lanes, number of girders, end diaphragms, and intermediate cross-beams are presented. An experimental program was conducted on six simply supported skew composite steel–concrete bridge models. Results from a finite element analysis showed excellent agreement with the experimental results. An extensive parametric study was conducted on prototype composite bridges subjected to OHBDC truck loading. The parametric study included more than 400 cases. The data generated were used to develop empirical formulas for shear distribution factors for OHBDC truck loading and also for dead load. An illustrative example is presented. Key words: bridges, codes of practice, composite, distribution, reaction, reinforced concrete, shear, skew, structural engineering, tests.

scholarly journals Development of innovative designs of bridge barrier system incorporating reinforcing steel or GFRP bars

2021 ◽  
Author(s):  
Hamidreza Khederzadeh
Keyword(s):  
Finite Element ◽  
Finite Element Modeling ◽  
Research Program ◽  
Ultimate Load ◽  
Phase Iii ◽  
Element Modeling ◽  
Yield Line ◽  
Gfrp Bars ◽  
Load Carrying ◽  
Actual Size

In harsh environment, corrosion of steel reinforcement causes durability problems. Glass Fiber Reinforced Polymer (GFRP) has emerged as an alternative to corrosion-related problem of steel bars in development of sustainable bridge deck and barrier walls. The current research program has been divided into five phases. In phase I, an extensive study has been conducted on pullout strength and bond behavior of pre-installed GFRP bars into concrete slabs and concrete cubes. In phase II, based on the Canadian Highway Bridge Design Code (CHBDC) factored applied moment at deck-wall junction, three configurations of GFRP-reinforced barrier detailing, using High-Modulus (HM) and Standard-Modulus (SM) GRFP bars, were proposed. The proposed barriers were tested by constructing five actual-size, 1.0-m long, PL-3 barrier models to determine their ultimate load carrying capacities and failure modes. In phase III, a full-scale PL-3 barrier made of GFRP-HM bars, with headed-end anchors as connecting bars to the deck slab, was constructed and tested under transverse static loading at both interior and exterior locations to-collapse to determine its crack pattern, failure mode and static ultimate load carrying capacity. In phase IV, from the trapezoidal failure pattern observed during testing the GFRP-reinforced PL-3 barriers, the research program was extended to revisit the triangular yield-line failure patterns in steel-reinforced PL-2 and PL-3 barriers specified in AASHTO-LRFD specifications. Experimental static tests to-collapse were conducted on constructed actual-size PL-2 and PL-3 steel-reinforced barriers, leading to more accurate expressions for their transverse load capacities developed based on the yield-line theory. In phase V, non-linear finite element analysis was conducted on GFRP-reinforced bridge barriers tested in phase III. The finite-element modeling was conducted to solely simulate the experimental test results for future research. A good agreement between experimental observations and numerical finite-element modeling was observed. Finally, this research led to (i) a more accurate design procedure for the GFRP - and steel-reinforced barrier wall and the barrier-deck joint, and (ii) design tables for the applied moment and tensile forces to be used to design the deck slab and the barrier deck-junction to resist transverse loading resulting from vehicle impact.

Monitoring and Defect Detection of an All-Composite Road Bridge

2000 ◽  
Author(s):  
Roger M. Crane ◽  
John W. Gillespie ◽  
Dirk Heider ◽  
Douglas A. Eckel ◽  
Colin P. Ratcliffe
Keyword(s):  
Structural Integrity ◽  
Theoretical Calculations ◽  
Detection Algorithm ◽  
Mode Shapes ◽  
Manufacturing Defects ◽  
Vibration Data ◽  
Composite Bridges ◽  
Longitudinal Joint ◽  
Composite Bridge ◽  
Sandwich Core

Abstract This paper presents the results of an ongoing investigation into the use of broadband vibration data to monitor the structural integrity and health of an all-composite road bridge. Bridge 1-351 on Business Route 896 in Glasgow, Delaware, was replaced with one of the first state-owned all-composite bridges in the nation in the fall of 1998. The bridge consists of two E-Glass/vinyl ester sandwich core sections (13-ft × 32 ft) joined by a longitudinal joint in the traffic direction. Each sandwich core section consists of a 28-inch deep core and 0.4-0.7-inch thick facesheets. Vibration data were obtained from the upper and lower surfaces of the bridge using a mesh of 1050 test points. From the modal information and the visualization of the data, several aspects of the structural behavior of the bridge were obtained. These characteristics include the interactions between the bridge and abutments; the effectiveness of the longitudinal joint to couple the deck sections; the effectiveness of the core to couple the face sheets; and the structural integrity and dynamic consistency of the entire structure. Mode shapes and natural frequencies were determined and are correlated with theoretical calculations and vibration analyses conducted for this bridge. A novel algorithm using the vibration data is being developed that enables local perturbations sensitive to the state of the material (e.g. manufacturing defects, material degradation or service damage) to be detected and spatially located in the bridge. This technique has been successfully validated for locating damage in 1-D beam structures and is being extended to the 3-D sandwich configuration of the bridge. By coupling this damage detection algorithm with the more conventional modal technique, the quality assurance/quality control and health monitoring of large composite bridge can be obtained.

Permafrost Thawing-Pipeline Interaction Advanced Finite Element Model

2009 ◽  
Author(s):  
Jianfeng Xu ◽  
Basel Abdalla ◽  
Ayman Eltaher ◽  
Paul Jukes
Keyword(s):  
Finite Element ◽  
Energy Demand ◽  
Large Scale ◽  
Limit State ◽  
The Arctic ◽  
Ultimate Limit State ◽  
Fe Model ◽  
Field Development ◽  
Thaw Settlement ◽  
Permafrost Thawing

The increasing energy demand has promoted the interest in exploration and field development in the Arctic waters, which holds one quarter of the world’s petroleum reserves. The harsh conditions and fragile environment in the arctic region introduce many challenges to a sustainable development of these resources. One of the key challenges is the engineering consideration of warm pipelines installed in permafrost areas; found mainly in shallow waters and shore crossings. Evaluations have to be made during the pipeline design to avoid significant thaw settlement and large-scale permafrost degrading. In this paper, a three-dimensional (3D) finite element (FE) model was developed to study the interaction between buried pipelines transporting warm hydrocarbons and the surrounding permafrost. This interaction is a combination of several mechanisms: heat transfer from the pipeline, results in permafrost thawing and formation of thaw bulb around the pipeline. Consequently, the thaw settlement of soil beneath the pipeline base results in bending strains in the pipe wall. For safe operations, the pipe should be designed so that the induced strains do not exceed the ultimate limit state conditions. The developed model helps in accurate prediction of pipe strains by using finite element continuum modeling method as opposed to the more commonly used discrete (springs) modeling and hand calculations. It also assesses the real size of the thaw bulb and the corresponding settlement at any time, thus preventing an over-conservative design.

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