Thomas J. Hatem Memorial Bridge Rehabilitation

Harford and Cecil Counties, Maryland

The Thomas J. Hatem Memorial Bridge carries 11 million vehicles per year between Harford and Cecil Counties along US 40 over the Susquehanna River. Opening in 1940, the existing 1.5 mile long bridge is comprised of 56 spans, is approximately 50’ wide, and is the oldest of the Maryland Transportation Authority’s seven toll facilities. Having provided a service life of over 70 years, the existing concrete and steel grid deck was in need of replacement in addition to numerous superstructure and substructure elements that required repair.

Wallace Montgomery (WM) was responsible for the preliminary and final design, and construction phase services associated with the $65 million dollar rehabilitation project. Work included preliminary evaluation of rehabilitation alternatives, MOT studies and design, design of permanent roadway and bridge signing, structural engineering design, historic recordation, erosion and sediment control design, environmental permitting, and construction phase services.

The project includes removal, replacement, and widening of the existing concrete filled steel grid deck with a new, lightweight, partially filled steel grid deck, including new concrete parapets and median barrier. The new deck and barriers were installed in four stages, while maintaining one lane of traffic in each direction at all times. The new lightweight deck offered a 20% weight reduction as compared to the original structure, increasing the bridge’s live load capacity. The new bridge deck is approximately 2’ wider than existing, increasing safety and available lane widths on the structure.

Rehabilitation of the existing superstructure, which is comprised of simple beam, Wichert girder; Wichert deck truss, and Wichert main through truss spans, included strengthening and repair to address Priority Items identified in Bridge Inspection Reports and critical members identified in bridge ratings. In total over 150 different repairs were completed at thousands of different locations across the bridge.

Concrete substructure repairs included localized concrete patching at numerous locations throughout the bridge. At seven locations, total pier replacement was found to be required based on preliminary investigations and testing carried out by WM. The pier replacements included a temporary support system to allow for pier replacement. In order to temporarily support the 800,000 pound reactions at the piers, temporary towers and foundations were designed by WM, and incorporated features such as helical piers to expedite construction.

Construction of this project began in spring 2008, and was completed ahead of schedule in June 2011. The Contractor on the project was the Joseph B. Fay Company.