Blending engineering and art
HNTB designed a 1,750-foot flyover that gives users of the Lakefront Trail a safe thoroughfare through one of the most congested points in the trail, Navy Pier, the top tourist attraction in the city. The design of the 16-foot wide flyover utilizes a central steel spine and a longitudinal spine-rib support system that allows the bridge to curve up, down and around.
Torsion is addressed through supporting columns topped with a saddle-like configuration that transitions the load downward. Specially designed lugs were created to link expansion joints to provide torsional continuity and allow for temperature-driven expansion and contraction. They also support any torque coming through the joint from imbalances that may occur on the surface, or vibrations from asymmetrical loading.
An LED lighting system illuminates the flyover, and a stainless-steel curb cover extends along the deck edges to create an even more uniform shape and appearance.