The second bridge over the Pirai River is under construction in the city of Santa Cruz de la Sierra. It will become the main access route from Santa Cruz to the new residential development Urubó Village. The bridge is required to be a signature structure that helps to enhance the high quality standards of the residential and business development while also being in harmony with the environment. Pedelta was appointed by the developer Urubó Village to conduct the design of the bridge.
The structure is conceived as an extradosed bridge. This typology is a cost-effective solution for medium-length span structures and is optimal to span wide valleys while reducing the number of piers.
The bridge will be 400 m long, distributed in four spans of lengths 69+131+131+69 m. The 18 m wide deck will accommodate four traffic lanes and two pedestrian walkways. The deck is a prestressed concrete box girder to be erected using balanced cantilever segmental construction with form travellers. Flexible double-walled piers will be monolithically connected to the deck. They are designed in order to minimize the effects due to imposed deformations and improve the cost of construction and maintenance of the bridge by removing the need for bearings and temporary supports. The pylons above the deck will be A-shaped, oriented parallel to the axis of the bridge and accommodate 10 cable stays arranged in a harp shape, which improves visibility and transparency.
Design was carried out meeting AASHTO LRFD, PTI, and other internationally recognized codes and recommendations for this type of bridges. The complex structural design not only provides an efficient and constructible solution, but also helps to enhance the aesthetics of the structure by combining a centred harp arrangement of cable stays with a singular A-shaped pylon.