• Steel and Composite Structures
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• v.38 no.6
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• pp.657-670
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• 2021

This paper presents a designing method for enhancing fire resistance of steel box bridge girders (closed steel box bridge girder supporting a thin concrete slab) through taking into account such parameters namely; fire severity, type of longitudinal stiffeners (I, L, and T shaped), and number of longitudinal stiffeners. A validated 3-D finite element model, developed through the computer program ANSYS, is utilized to go over the fire response of a typical steel box bridge girder using the transient thermo-structural analysis method. Results from the numerical analysis show that fire severity and type of longitudinal stiffeners welded on bottom flange have significant influence on fire resistance of steel box bridge girders. T shaped longitudinal stiffeners applied on bottom flange can highly prevent collapse of steel box bridge girders towards the end of fire exposure. Increase of longitudinal stiffeners on bottom flange and web can slightly enhance fire resistance of steel box bridge girders. Rate of deflection-based criterion can be reliable to evaluate fire resistance of steel box bridge girders in most fire exposure cases. Thus, T shaped longitudinal stiffeners on bottom flange incorporated into bridge fire-resistance design can significantly enhance fire resistance of steel box bridge girders.

• Corrosion Science and Technology
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• v.3 no.4
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• pp.166-171
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• 2004

Recent developments in Bridge Management Systems (BMS) and in Life-Cycle Cost (LCC) of bridges, have raised the need for evaluation procedure of future condition (Deterioration) of a bridge. Predicting future deterioration is not an easy task due to limited past data to extrapolate from and also due to difficulty in measuring actual deterioration such as section loss of steel on an actual steel bridge. Also, increase in live load and reduction of resistance are random variables, thus a probabilistic approach should be adopted for determining the future deterioration. Due to difficulties in evaluation of future deterioration on steel bridges, accepting uncertainties within a reasonable error, a deterministic procedure using bridge condition rating can be a useful tool for projection of future condition of bridges to identify repair and maintenance needs. The object of this paper is to determine applicability of evaluating deterioration of steel bridge components based on Bridge condition ratings. Bridge condition ratings of bridge components show wide variation for bridges of same age and does not directly correlate well with the age of the bridge and/or deterioration of the bridge. High uncertainty can be reduced by breaking down the rating and by sensitivity analysis. From refined condition rating data, generalized deterioration profile of structures based on age can be derived. Examples are shown for sample bridges in USA. Approximately, 3,000 short to medium span steel bridges were listed in the inventory database. Results show wide variation of rating factors but by subdividing the Bridge condition ratings for various categories general deterioration profiles of steel bridges can be determined.

• Steel and Composite Structures
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• v.26 no.5
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• pp.583-594
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• 2018

Although a lot of experimental and analytical investigations have been carried out for steel bridge piers made of SS400 and SM490, the formulas available for SS400 and SM490 are not suitable for evaluating ultimate load and deformation capacities of steel bridge piers made of high strength steel (HSS) SM570. The effect of various parameters is investigated in this paper, including plate width-to-thickness ratio, column slenderness ratio and axial compression force ratio, on the ultimate load and deformation capacities of steel bridge box piers made of SM570 steel subjected to cyclic loading. The elasto-plastic behavior of the steel bridge piers under cyclic loads is simulated through plastic large deformation finite element analysis, in which a modified two-surface model (M2SM) including cyclic hardening is employed to trace the material nonlinearity. An extensive parametric study is conducted to study the influences of structural parameters on the ultimate load and deformation capacities. Based on these analytical investigations, new formulas for predicting ultimate load and deformation capacities of steel bridge piers made of SM570 are proposed. This study extends the ultimate load and deformation capacities evaluation of steel bridge piers from SS400, SM490 steels to SM570 steel, and provides some useful suggestions.

• Steel and Composite Structures
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• v.27 no.3
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• pp.285-295
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• 2018

In this paper, the bearing capacity of a non-eccentric and eccentric tubular, concrete-filled, steel bridge pier was studied through the finite element method. Firstly, to verify the validity of the numerical analysis, the finite element analysis of four steel tube columns with concrete in-fill was carried out under eccentric loading and horizontal cyclic loading. The analytical results were compared with experimental data. Secondly, the effects of the eccentricity of the vertical loading on the seismic performance of these eccentrically loaded steel tubular bridge piers were considered. According to the simulated results, with increasing eccentricity ratio, the bearing capacity on the eccentric side of a steel tubular bridge pier (with concrete in-fill) is greatly reduced, while the capacity on the opposite side is improved. Moreover, an empirical formula was proposed to describe the bearing capacity of such bridge piers under non-eccentric and eccentric load. This will provide theoretical evidence for the seismic design of the eccentrically loaded steel tubular bridge piers with concrete in-fill.

• Journal of the Korean Society for Railway
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• v.9 no.6 s.37
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• pp.717-724
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• 2006

The major objective of this study is to investigate the effects and application of improvement for railway steel plate girder bridge by resilient panel track system. It analyzed the mechanical behaviors of steel plate girder bridge with applying resilient panel track system on the finite element analysis and laboratory test for static & dynamic characteristics. As a result, the improvement of steel plate girder bridge with resilient panel track systems are obviously effective for the static & dynamic response which is non-ballast steel plate girder bridge. The analytical and experimental study are carried out to investigate resilient panel track system decrease vertical acceleration and deflection on steel plate girder bridge for serviceability. And the resilient panel track system reduced dynamic maximum displacements (about 59%) and stresses (about 82%), the increase of dynamic safety is predicted by adopting resilient panel track system. From the dynamic test results of steel plate girder bridge, it is investigated that vertical acceleration and deflection is very low with applying resilient panel track system. The servicing steel plate girder bridge with resilient panel track system has need of the reasonable improvement measures which could be reducing the effect of static and dynamic behavior that degradation phenomenon of structure by an unusual response characteristic and a drop durability.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.437-446
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• 2006

The major objective of this study is to investigate the effects and application of improvement for railway steel plate girder bridge by resilient panel track system. It analyzed the mechanical behaviors of steel plate girder bridge with applying resilient panel track system on the finite element analysis and laboratory test for static & dynamic characteristics. As a result, the improvement of steel plate girder bridge with resilient panel track systems are obviously effective for the static & dynamic response which is non-ballast steel plate girder bridge. The analytical and experimental study are carried out to investigate resilient panel track system decrease vertical acceleration and deflection on steel plate girder bridge for serviceability. And the resilient panel track system reduced dynamic maximum displacements(about 59%) and stresses(about 82%), the increase of dynamic safety is predicted by adopting resilient panel track system. From the dynamic test results of steel plate girder bridge, it is investigated that vertical acceleration and deflection is very low with applying resilient panel track system. The servicing steel plate girder bridge with resilient panel track system has need of the reasonable improvement measures which could be reducing the effect of static and dynamic behavior that degradation phenomenon of structure by an unusual response characteristic and a drop durability.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.2
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• pp.175-182
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• 2010

A composite safety barrier for bridge has been developed and the performance of the composite safety barrier for bridge has been compared with the steel safety barrier for bridge through computer simulation. As the structural strength performance, the composite safety barrier for bridge is superior to the steel safety barrier for bridge according that the deformation of the composite safety barrier for bridge is 17.0% of that of the steel safety barrier for bridge. As the passenger protection performance, the composite safety barrier for bridge is superior to the steel safety barrier for bridge according that THIV and PHD of the composite safety barrier for bridge are 47.1% and 49.0% respectively of those of the steel safety barrier for bridge. As the behavior of the vehicle after crash, the composite safety barrier for bridge is superior to the steel safety barrier for bridge showing the increased exit velocity and the reduced exit angle. Both of the steel and composite safety barrier for bridge are not scattered in the analysis.

• Steel and Composite Structures
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• v.43 no.3
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• pp.353-362
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• 2022

Bridge fire hazard has become a growing concern over the last decade due to the rapid increase of ground transportation of hazardous materials and resulting fire incidents. The lack of fire safety provisions in steel bridges can be a significant issue owing steel thermal properties that lead to fast degradation of steel properties at elevated temperatures. Alternatively, the development of composite action between steel girders and concrete decks can increase the fire resistance of steel bridges and meet fire safety requirements in some applications. This paper reviews the fire problem in steel bridges and the fire behavior of composite steel-concrete bridge girders. A numerical model is developed to trace the fire response of a typical bridge girder and is validated using measurements from fire tests. The selected bridge girder is composed by a hot rolled steel section strengthened with bearing stiffeners at midspan and supports. A concrete slab sitting on the top of the girder is connected to the slab through shear studs to provide full composite action. The validated numerical model was used to investigate the fire resistance of real scale bridge girders and the effect of the composite action under different scenarios (standard and hydrocarbon fires). Results showed that composite action can significantly increase the fire resistance of steel bridge girders. Besides, fire severity played an important role in the fire behavior of composite girders and both factors should be taken into consideration in the design of steel bridges for fire safety.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.561-564
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• 2004

Steel sheet pile can be alternative material for bridge abutment for. The steel sheet pile bridge abutment is new and replacement bridge abutment due to its aesthetically attractive and cost effective. Use of embedded steel sheet piling brings savings in dead load, provides a compliant retaining wall, and permits speedier construction. In addition, for replacement bridge projects, traffic interruption can be minimized. It is hoped that this study will encourage designers and constructors to consider a steel substructure option more frequently during the conceptual and preliminary design phases of projects and thereby to take advantage of the potential to construction more efficiently. In this paper, an analysis of stress and strain for steel sheet pile bridge abutment was conducted. From the analysis results, the stress and strain characteristics of steel sheet pile bridge abutment with variations of steel sheet pile parameters is suggested.

• Steel and Composite Structures
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• v.44 no.6
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• pp.753-768
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• 2022

In this study, a graphical automatic system is developed in order to investigate the stress redistribution of structural members in a steel cable-stayed bridge. The generalized Maxwell model is selected for stress relaxation estimation, and it is carefully verified and applied to all the cable members of a steel cable-stayed bridge to investigate its stress relaxation. A set of stress relaxation parameters in all cables is determined using the fmincon optimization function. The stress redistribution of the steel cable-stayed bridge is then analyzed using ABAQUS. To shorten the investigation time, all the aforementioned phases are built up to be an automatic system. The automatic system is then employed to investigate the effect of cable cross-section areas and girder spans on stress redistribution. The findings from these studies show that the initial tension in the cables of a steel cable-stayed bridge should be kept to less than 55% of the cable's ultimate strength to reduce the effect of cable stress relaxation. The cable space in a steel cable-stayed bridge should be limited to 15,000 mm to minimize the effect of cable stress relaxation. In comparison to other structural members of a steel cable-stayed bridge, the girders experience a significant stress redistribution.