Examples of Finite Element Models of Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 607

was developed using ANSYS [6.10]. The concrete slab was connected to the
steel girder by headed studs with a diameter of 22 mm. The stud spacing was
initially set to 200 mm. The steel girder was represented by shell elements
(SHELL63) available in ANSYS element library, the concrete slab was mod-
eled with solid element (SOLID45), and spring elements (COMBIN14)
were chosen to represent the headed shear studs. In the study, the corre-
sponding nodes of the concrete slab and steel girder were connected by
spring elements in the longitudinal direction and coupled in the other direc-
tions. The characteristic of the spring element was derived from load-slip
curves obtained by stud push-out tests [ 7.12 ] . The change of the stud stiffness
during the design life was not taken into account. The train type considered
in the study [ 7.11 ] was a high-speed train. It was composed of a locomotive
followed by eight-passenger cars and another locomotive. The length of the
locomotive was 19.7 m, while the length of the passenger car was 26.1 m.
The average static axle loads for the locomotives and passenger cars were
176.4 and 112.9 kN, respectively. The train speed was set to 300 km/h.
The dynamic response of the bridge was predicted through a moving load
model and, alternatively, through a train-bridge interaction model. In the
moving load model, the train was simplified as a series of moving loads,
while the train-bridge interaction model incorporated subsystems for the
train and the bridge. Each vehicle is considered as an independent entity
with one car body, two bogies, and four wheel sets. The bogies and the
wheel sets were linked by horizontal and vertical springs and dampers.
The train subsystem and the bridge subsystem were coupled by the interac-
tion forces and the compatibility of the displacements at the contact points
[6.13]. It was shown that during the train passage, variable amplitudes of
fatigue loading were generated. Since the train-bridge interaction model
predicted the most realistic behavior of the bridge subjected to moving
trains, it was recommended for further studies.
Brackus [ 7.13 ] discussed that full-depth, precast panel deck systems were
becoming common in bridge installation and repair. Therefore, the struc-
tural behavior of these systems was the subject of the analyses performed
in the study. A steel I-girder bridge containing a precast panel deck system
was demolished and provided two full-scale specimens for this project.
Destructive testing was performed on the specimens to investigate three fail-
ure modes comprising flexural, beam shear, and punching shear. Finite ele-
ment models were developed using ANSYS [6.10] software to replicate
experimental behavior. It was found that the elastic, postelastic, and ultimate
behavior of the full-scale bridge sections containing precast panel deck