Chongqing Tiandi Pedestrian Overpass
Chongqing Tiandi Pedestrian Overpass is located at the intersection of Changhe Road and Jiabin Road. At the north end of the overpass, there is a 13 m-long by 4.8 m-wide viewing platform. One side is equipped with a 3 m-wide stairway, and the other side has a 1.5 m-wide stairway and a 1.5 m-wide escalator, both connecting to the Jiabin Road sidewalk.
The main girder of the overpass spans Jiabin Road with span lengths of 26.75 m + 21.75 m + 26 m, totaling 74.5 m. The girder height is 1.1 m with a standard deck width of 4.8 m. Toward the south end, it widens to 9.15 m to connect with a landscaped walkway, and a 3 m-wide pedestrian stairway links to the Changhe Road sidewalk. The deck has a longitudinal slope transitioning from 0.5% to 5.23% and a ±1.0% cross slope.
Superstructure Design
The overpass uses a tapered steel box girder structure. The girder spans 74.5 m in length, with a constant height of 1.1 m and width varying from 4.8 m to 9.15 m. Cantilevered edges extend 0.8 m beyond the girder; the bottom plate width ranges from 3 m to 7.35 m. The support spacing alternates between 1.6 m and 3.6 m. The top and bottom decks are 14 mm thick, and the web plates are 12 mm thick. Plate stiffeners are installed at 0.4 m intervals, and transverse diaphragms at mid-span occur every 2 m. A 30 mm camber (pre-arched curvature) is built into the mid-span sections between piers P1–P2 and P3–P4, following a parabolic (second-order) curve.
Substructure
The steel platform and main girder rest on circular piers 0.8 m in diameter, supported by piles 1.2 m in diameter. The piers are clad in aluminum composite panels; the panel framing is made of aluminum-alloy steel tubing. The panel color is recommended to match the girder’s design but can be customized per owner requirements. The construction contractor must engage experienced manufacturers for detailed design and execution of the bridge’s architectural finish.
All pile foundations are rock-socketed, embedded at least three diameters into moderately weathered bedrock. The minimum single-pile axial compressive strength at the pile tip must be no less than 5.3 MPa, and the rock socket length at the bottom must exceed 5.0 m.
