Location: Milwaukee, Wisconsin
One of two auxiliary interstates in the metropolitan area, the 3.75-mile Lake Freeway spur route serves the lakefront and the Port of Milwaukee and connects downtown with the southeastern suburbs of St. Francis, Cudahy, and South Milwaukee. The project, which included major improvements to the freeway and the Daniel Hoan steel tied-arch bridge, ensures connectivity with the Port of Milwaukee and economic vitality far into the future.
Michael Baker International was the prime consultant, and engineering services included preliminary and final roadway and structure design; development of plan, specification, and estimate packages; preparation of an environmental report; agency, railroad, utility, and subconsultant coordination; survey; traffic analysis; safety analysis; traffic control; construction staging; risk assessment; constructibility reviews; construction sequencing; and bridge load rating calculations.
The project was divided into three major segments: the I-794 East-West, from the Milwaukee River to the Lake Interchange, which included removal and replacement of numerous viaducts and ramps; the Lake Interchange segment, from IH 794 East-West to the Hoan Bridge, which included concrete overlay and rehabilitation; and the Hoan Bridge from Lake Interchange to Carferry Drive, which included removal and replacement of the bridge deck, miscellaneous structural repairs and modifications, blast cleaning, and repainting. The rehabilitation and redecking included more than 30,000 feet of bridge structures.
This high-profile project involved extensive stakeholder, utility, railroad, and agency coordination. Michael Baker performed in-depth investigations to optimize constructibility, phasing, construction durations and staging, and contract packaging, to minimize public and stakeholder impacts. Complex staging plans and a traffic management plan were required due to the 50,000 average daily traffic and to accommodate traffic through the Lake Interchange. Michael Baker completed the final design on an aggressive schedule, completing 2,500 bridge plan sheets in just eight months. Michael Baker provided constructibility reviews throughout the design process to address issues such as complex staging and scheduling, contractor access, and navigational clearance. Michael Baker was actively involved in the construction, though the design liaison process provided valuable insight on complex design issues.
The Hoan Bridge is a three-span, steel, half-through arch with spans of 270 feet, 600 feet, and 270 feet. The project involved numerous structural steel repairs and the replacement of the deck using staged construction that was investigated using a three-dimensional finite-element model. Load factor rating and load and resistance factor ratings were required for all of the bridges down to the foundation. Additional bridge types included post-tensioned concrete box girders; complex steel girder floor beam stringers, using a three-dimensional grid analysis; and steel plate girders. The project also included the replacement of deteriorated concrete barriers, sign bridge repair and replacement, and incorporation of intelligent transportation system components into the final design. Design tasks also included repainting the entire structure and a number of other bridge repairs, including joint and bearing replacements.