Experimental Study on Seismic Performance of Reactive Power Concrete Box Piers

Designing the reasonable cross-section and the structural conformation, three Reactive power concrete box piers samples were designed and studied under the constant axial force and reversed horizontal loads. The effect of the reversed horizontal load on the seismic performance of RPC box pier was studied. Such seismic performance as ductility, hysteresis curve, skeleton curve, etc. of RPC box piers is studied by pseudo-static test on three RPC box piers. The simulation results shows that RPC box piers exists excellent performance of resisting seismic force, the direction of horizontal load significant affect that performance, and the performance of resisting seismic force for the pier loaded by the force from main axial direction are better than that from other direction.

Innovative Design and Construction of Chesapeake and Delaware Canal Bridge

An outstanding accomplishment of bridge design, construction, and management, the Chesapeake and Delaware (C&D) Canal Bridge demonstrates that precast, segmental, cable-stayed bridges can be an economical and aesthetically pleasing solution in an area of the country where steel bridges are predominant. The C&D Canal Bridge is the first major concrete segmental cable-stayed bridge structure to be completed in the Northeast. The $58 million C&D Canal Bridge is a precast concrete, segmental structure 1417 m (4,650 ft) in length. Twin parallel box girders were designed to provide six lanes of travel with a total bridge width of 38.7 m (127 ft), with each precast box girder containing three 3.65-m (12-ft) lanes and two 3-m (10-ft) shoulders. Innovative construction techniques, economy, and aesthetics were the primary focus of the construction and design solutions used for the 229-m (750-ft) cable-stayed main-span crossing. The bridge was completed on schedule, with no claims or suits, at a cost slightly under the original bid. A quality-based selection process for the bridge designer, a prequalification process for the selection of the contractor, a disputes review panel, and informal partnering during construction all contributed greatly to a very successful project. The use of precast concrete elements provided an efficient and time-saving technique for the construction of this bridge. In addition, precast concrete box girders, box piers, and delta frames were designed to anchor the cable stays and make the parallel trapezoidal box girders monolithic throughout the main span.