Iowa State University needed a large pedestrian bridge that spanned over a parking lot and a busy four-lane street to allow fans safe access on game day from the new parking and tailgating lot into
Jack Trice Stadium. The concept for an open-air pedestrian bridge with no roof was conceived that would not only prove to be functional and secure, but a visually captivating and prominently visible entrance to the university campus.
Wells produced precast concrete columns and beams, double tees, solid slabs and architectural solid walls to create a stunning design for the bridge. Stretching an impressive quarter mile in length, the bridge includes two large stair towers crafted from architectural precast concrete panels,
embellished with ISU-themed lighting that provides safety and visibility to pedestrians.
Given the considerable span of the bridge, utilizing steel throughout the entire structure would have resulted in significant costs. With an emphasis on a cost effective and durable design, only a small amount of structural steel was used for the main span, while precast concrete was used for most
of the structure, including the walkway’s slab sections. The final design solution utilized 77-foot long, 42-inch-deep double tees, offering a cost-effective solution for the university. Other sections of the project encompass an elevated plaza connecting to the stadium, consisting of precast concrete
columns and beams with hollow core, and an additional smaller walkway, all of which demonstrated the versatile application of precast concrete to support the various scopes of the project.
To achieve the desired aesthetic of recessed lights in the upper deck or lid of the stair tower, a solution had to be found to allow for electrical wiring through the panels. Incorporating electrical boxes into wall panels posed a challenge due to the presence of structural strands. Overcoming this challenge involved using 8-inch wall panels to accommodate the electrical components while working within the
constraints of the structural strands within the wall panels.
The construction of the East Gateway Bridge showcases the ingenuity and efficiency that can be achieved in pedestrian bridge design and construction. By opting for cost-effective prefabricated
elements, Wells and other project partners successfully addressed dynamic loading concerns while providing a durable and long-lasting structure. |