Project Description
The Gazapa Bridge is part of the new network extension project in the city of Cucuta. Completed in 2008, it stretches 240 m across the wide Pamplonita River to provide an additional and more direct connection between the city and the East ring road, which has considerably relieved congestion.
The bridge is composed of three spans of lengths: 60+120+60 m. The deck is a continuous girder which is monolithically connected to two hollow concrete piers of 11 m in height and a cross-section with dimensions 5.6x4 m. Together they form a portal frame supported by neoprene bearings at the abutments. The deck is 10.9 m wide and consists of a single-cell, post-tensioned concrete box girder, with a variable depth of 2.5 to 6.75 m. The foundations of the bridge consist of 1.5 m diameter piles.
Design/Construction Approach
Due to the significant height of the bridge and to minimize the environmental impact on the river, the balanced cantilever method was selected. This construction method requires careful displacement prediction and control, and for that reason advanced bridge design software was used (RM Bridge). Since the width of the deck is approximately 20% of the main span length, important shear lag effects were considered in order to correctly predict the stresses and displacements of the bridge in every construction phase.