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displacements between the deck slab and bearing supports. The study pro-
posed a simplified method for the calculation of these displacements based
on the elastic girder stresses and transverse girder stiffnesses, which were
shown to compare well with results given by the finite element method.
In addition, the proposed method was shown to give results that compared
well with experimental data from a 0.4-scale model subject to shake table
excitation. Furthermore, parametric studies were described and showed that
typical I-girder superstructures were able to accommodate large transverse
drifts (up to 17% of the girder height) while remaining in the elastic range.
These large drifts were possible without distress to the slab-to-girder con-
nection, by omitting shear studs over a short length of the girder at the sup-
port cross-frame locations. Based on the preceding text, a step-by-step
procedure was proposed for evaluating the transverse displacement, stiffness,
and capacity of the steel girder superstructures in the region of the end and
intermediate supports. The developed finite element model was developed
for a 9.14 m length of the bridge girder, equal to half of the actual bridge
model girder length, with symmetrical boundary conditions at midspan,
using elastic shell elements for the flanges and web. The finite element model
was generated using SAP2000 [6.20]. Rows of shear studs were placed every
460 mm for the partially composite bridge model except the ends of the
bridge. Elements and restraints were used in the finite element model to
allow for each shear stud to connect the girder to an assumed transversely
rigid deck slab resulting in a constant transverse displacement in the top
flange. Contact between the deck slab and top flange was modeled using
rigid pin-ended links between the deck slab and edge of the flange. Web
stiffeners were modeled using elastic shell elements at the cross-frame loca-
tions, with intermediate stiffeners between the cross frames generally
neglected except in specific cases where the effect of these was investigated.
A rotational spring at the base of the girder was used to model the rotational
bearing stiffness.
mation of the long-term performance of selected pilot bridges and to
develop a methodology to assess bridge performance. The author discussed
that finite element modeling of the pilot bridges was intended not only to
assist with instrumentation decisions but also to provide further insight into
the behavior of these bridges, which cannot be achieved solely from field
testing of the bridges. Finite element models were developed to study the
effect of the inclusion of various bridge parameters in the model, such as
bridge skew, degree of composite action, thermal gradient, and level of
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