Project Description

Pedelta designed an arch bridge over the Torola River, in northern El Salvador.  This structure is necessary to cross the future reservoir created by El Chaparral Hydroelectric Plant, which is currently under construction. The project comprised the detailed structural design and analysis of the arch bridge as well as the design of the roadway access to both bridge approaches.

The arch bridge is a 143 m structure with an 8.5 m wide concrete deck. The deck structure is supported by two parallel cast-in-place reinforced concrete arches to be erected using cantilever construction methods and tiebacks.

The arch main span is 80 m long with a vertical clearance of 21 m. The deck is a continuous concrete girder with a double-tee as its cross-section, to be built using span-by-span construction methods and traveler form as falsework.

Design/Construction Approach

The substructure is designed using shallow foundation techniques with vertical anchorages on some of its footings to provide an extra load needed for stabilization during the different construction stages.

One of the main challenges of this type of bridge lies on the erection method, because the arch is built in cantilever and must be suspended by cable stays until it is closed. A temporary tower has been designed to anchor the front and back cable stays during this construction stage.

Client
Comisión Ejecutiva Hidroeléctrica del río Lempa
Location
Carolina (El Salvador)
Key Elements
Concrete Arch, Temporary Cable Stays, Cantilever Construction
Services
Feasibility Studies/Conceptual Design
Detailed Design