Girders Research Papers - Academia.edu (original) (raw)

This paper is aimed at studying the elastoplastic behavior of longitudinally stiffened girder webs subjected to patch loading and bending. The investigation is carried out by means of nonlinear finite element analysis to study the... more

This paper is aimed at studying the elastoplastic behavior of longitudinally stiffened girder webs subjected to patch loading and bending.
The investigation is carried out by means of nonlinear finite element analysis to study the structural behavior of the girder components
(flanges, web and stiffener) at ultimate limit state. Initial geometrical imperfections, plastic material behavior and large deflection effects
are considered in the model. For the numerical model validation, the computer results from the simulations are compared with
experimental results taken from the literature. A parametric study was carried out in order to investigate the influence of the applied
bending moment and the relative location of the stiffener on the ultimate strength to patch loading.

The process of designing a typical simply supported girder for service loads is well established. However, the fact that the girder will be suspended by cables during the erection phase affects the safety of the girder. Initial camber,... more

The process of designing a typical simply supported girder for service loads is well established. However, the fact that the girder will be suspended by cables during the erection phase affects the safety of the girder. Initial camber, such as in the case of prestressed concrete girders, aggravates the problem. The presence of cambet causes the resultant of the load to be located above the center of torsion of the member, thus causing an increase in torsional moment with increasing lateral displacement. This behavior reduces the critical buckling load of the member and the safety of the girder. This paper presents the differential equations necessary to obtain the critical buckling load for a cambered member subjected to its own weight during lifting. Support conditions considered include: (1) Simply supported; (2) suspended by cables at the ends; and (3) suspended by cables located an equal distance from the ends of the member. Finally, sample graphs of the results are included to show the significance of camber in calculating the critical buckling load of a member.

In this study, a three dimensional finite element analysis was utilized to study the behavior of reinforced concrete T-girders with and without web openings under pure torsion by using ANSYS APDL 15.0 program. Fourteen reinforce concrete... more

In this study, a three dimensional finite element analysis was utilized to study the behavior of reinforced concrete T-girders with and without web openings under pure torsion by using ANSYS APDL 15.0 program. Fourteen reinforce concrete T-girders were analyzed; one of the girders (without web openings) was modeled as a control girder. The analysis variables considered for the other girders are: size, shape, position of web openings, number of web openings and the method was used to strengthen the member at openings, (using internal deformed steel bars as in the case where the openings are planned before casting the girders). To study the general behavior of finite element models, torque-angle of twist plots at the end of the span near the loaded arms were represented. From this relation, it was showed a decreasing in the strength of the T-girders with web openings under the torsional loads and increasing of the angle of twist. The results were analyzed in terms of torque twist characteristics; ultimate torque, crack patterns, crack width, warping and stresses. These terms were presented and a comparison between the finite element results was made.

Steel girder bridges in particular can suffer the consequences of skew, and addressing the topic of how to mitigate the effects of skew in these structures is important. This paper addresses skew in several contexts, including how skew... more

Steel girder bridges in particular can suffer the consequences of skew, and addressing the topic of how to mitigate the effects of skew in these structures is important. This paper addresses skew in several contexts, including how skew affects the behavior of steel girder bridges and their components as well as the impacts of skew on the detailing, fabrication, and erection of steel girder bridges. In addition to discussing the problems associated with skew, the paper offers ideas and techniques for minimizing or avoiding skew and for analyzing, understanding, and mitigating the effects of skew when it cannot be avoided.

The U.S. Departments of Transportation adopted the AASHTO LRFD Bridge Design Specifications during the year 2007, which is mandated by AASHTO and FHWA. The application of LRFD specification initiated numerous research works in this field.... more

The U.S. Departments of Transportation adopted the AASHTO LRFD Bridge Design Specifications during the year 2007, which is mandated by AASHTO and FHWA. The application of LRFD specification initiated numerous research works in this field. This investigation addresses the LRFD and Standard design methodologies of concrete deck slab, deck overhang, barrier and combined barrier-bridge overhang. The purpose of this study is to propose a simplified manual design approach for the barrier-deck overhang in concrete bridges. For concrete deck slab overhang and barrier, application ofNational Cooperative Highway Research Programcrash test is reviewed. The failure mechanism, design philosophy and load cases including extreme event limit states for barrier and overhang are discussed. The overhang design for the combined effect of bending moment and axial tension is probably the most important part of the design process. The overhang might be a critical design point of the deck with significantl...

Out-of-plane stresses due to the wedging effect of the strands caused high stress concentration at the end of the transition zone of Florida bulbtee girders. Adding the hydrostatic stresses due to grout pressure in the posttensioning... more

Out-of-plane stresses due to the wedging effect of the strands caused high stress concentration at the end of the transition zone of Florida bulbtee girders. Adding the hydrostatic stresses due to grout pressure in the posttensioning ducts severed the tensile stresses in the web section and caused some crack initiation between the ducts and on the surface of the girders. Other related factors were found to contribute to these stresses. Among these factors were the shape of the posttensioning ducts, and the type of the duct material. Two fully instrumented 22.9-m-long Florida bulbtee end girders were prepared and tested under typical field conditions. Testing results indicated that stress accumulation due to the grout pressure was more severe in ducts with oval cross sections than in the round ones. Although steel ducts were used in the full-scale field testing, a comparative study using 3D nonlinear finite-element analyses showed that cracking was even more severe when using high-de...

This paper presents finite-element and fracture mechanics studies of plate girders with corrugated webs. The failure mode of this type of girder under fatigue loading is distinguished by its location in the tension flange and is discussed... more

This paper presents finite-element and fracture mechanics studies of plate girders with corrugated webs. The failure mode of this type of girder under fatigue loading is distinguished by its location in the tension flange and is discussed in detail. A comprehensive nonlinear finite-element ...