Design and Construction of the Deh Cho Bridge Challenges, Innovation, and Opportunities

摘要

The Deh Cho Bridge will be the first bridge structure crossing the Mackenzie, Canada's longest river. When the bridge is opened it will permanently replace ferry and ice road services along Highway 3 connecting Yellowknife in the Northwest Territories with Highway 1 in the South. The bridge's remote location in the North with severe winter conditions of up to -40 °C requires meticulous planning and is an extraordinary challenge for men and equipment (see Figure 1). Innovative design methods led to the design of a unique 1045 m long continuous cable supported superstructure with expansion joints only at the abutments. The design employs ecological light-weight design principles as well as fast-tracked fabrication and erection methods. Structural performance of the superstructure has been optimized for construction and service scenarios allowing a high degree of repetition as well as aesthetic proportions and rhythm. Serious design challenges often require new philosophies and strategies. On the other hand, they provide exceptional opportunities for innovation. The Assembly-line Design Approach, the Failure Mechanism Concept, and the Fuse Design Philosophy have been specifically developed for the Deh Cho Bridge with the purpose to cope with extraordinary schedule and design requirements.