Straight and curved steel I-girder bridges - Computational Analysis and Design of Bridge Structures - page 224

study was made with the consideration of creep and shrinkage that the deck
being constructed still matched up in elevation to the deck poured in the
previous phase, not causing noticeable misalignments in the deck.

7.4 2d and 3d IlluStrated exaMPle of a
Curved Steel I-gIrder BrIdge—roCk Creek
traIl PedeStrIan BrIdge, Maryland

The Rock Creek Trail Pedestrian Bridge serves as a connection for the
Rock Creek Hiker-Biker Trail and provides a safe crossway for pedestri-
ans and cyclists. The bridge spans over Veirs Mill Road (MD-586) near
Rock Creek Park in Montgomery County, Maryland. Table 7.2 lists the
parameters of the curved portion of the bridge. At the erection stage of
the construction process, the curved inner girder at the supports of Piers 1
and 3 was uplifted after the temporary supports were released. Due to the
aberrant response of the curved spans during construction, the spans were
modeled and studied for two stages: (1) bridge under construction with
dead load only and (2) bridge under live load. This two-span, two-girder

Table 7.2 Description of the Rock Creek Trail Pedestrian Bridge structure
Description Variable

Number of girders 2

Number of spans 2

Radius of curvature of girder 1 (inner) 220.0 ′ (67 m)

Radius of curvature of girder 2 (outer) 230.0 ′ (70 m)

Span lengths of girder 1 2 @ 161.33 ′ (49.2 m)

Span lengths of girder 2 2 @ 168.67 ′ (51.4 m)

Spacing between girders

10.0 ′ (3 m)

Roadway width 29.0 ′ (8.8 m)

Overhang width, left and right 2.33 ′ (0.7 m)

Curb width, left and right 1.33 ′ (0.4 m)

Design slab depth (excluding integral wearing
surface)

9.0 ″ (229 mm)

Integral wearing surface 0.5 ″ (13 mm)

Haunch depth and width 5.0 ″ and 24.0 ″ (127 and 610 mm)

Type of concentration Composite

Ultimate strength of concrete 4.0 ksi (27.6 MPa)

Yield strength of steel 50 ksi (A992) (345 MPa)

Live loading H-10 and pedestrian loading