The geometric design of curved incrementally launched prestressed concrete bridges

Incrementally launched prestressed concrete bridges may be constructed either straight or on a curved alignment. The geometric design of launched straight bridges, with or without a vertical curve, or horizontally curved bridges on a straight grade is relatively straightforward. However, the geometric design of launched bridges which are curved in both plan and elevation is somewhat more complex. The geometric design of launched prestressed concrete bridges is an important structural design consideration, since out-of-tolerance positioning of launched concrete bridges can induce large forces into the bridge superstructure. This paper presents one approach for the geometric design of launched concrete bridges which are curved in both plan and elevation. The design theory is discussed and spreadsheets are presented to facilitate design calculations. (a) For the covering entry of this conference, please see ITRD abstract no. E214936.