Precast Options for Bridge Superstructure Design

Precast construction offers many options for bridge owners and designers: Traditional solutions are I-girders, slab girders and box girders with traditional I-girders being replaced by a new family of more efficient bulb T girders with depths ranging from 1200 to over 2400 mm. Box and trapezoidal girders provide lower span/depth ratios and are more aesthetically pleasing. Each province has their own limitations on the size and weight of bridge members that can be transported by road. Spliced girder construction can be used when these limits are exceeded; here girder elements can achieve spans of 60 to 80 m. Custom solutions can be explored for large projects where the tooling-up costs can be spread over a large number of similar precast concrete components. The fast erection of precast bridge components can speed up bridge construction. Installation in urban areas can occur in off-peak and at night to minimize traffic interruptions. Multiple cranes, barges, temporary bridges, launching trusses can be implemented on difficult sites to help protect the environment. Safe efficient precast concrete construction with built-in durability will ensure the lowest total cost of ownership for the traveling public. For the covering abstract of this conference see ITRD number E