Reclamation for a Bulk and Container Terminal Complex in a High Seismicity Region

The Pacific coast of Colombia is currently home to one of the biggest maritime infrastructure projects under development in Latin America. Located on the Aguadulce Peninsula, facing the Port of Buenaventura, with an area of more than 35 hectares, the land reclamation project is a key part of an $800 million program to develop the Boscoal (bulk handling) and SPIA (container) terminals. The Aguadulce Peninsula is a greenfield site, located in one of the highest seismic regions in the world. The site is characterized by the presence of thick layers of very soft marine sediments overlying stiffer layers of clay and mudstone. The site experiences heavy rainfall all year long and the portions of both terminals facing the sea can be exposed to tidal variations of up to 5 meters. This paper describes the technical solutions for the land reclamation implemented in the different upland portions of the two terminals and how the technical and logistic challenges brought about by the presence of soft soils, the high seismicity of the region, the remoteness of the site and lack of good fill soils were overcome. Because of the high cost of importing good quality fill materials, optimization of available in-situ materials for reuse as part of the land reclamation was necessary. Thus, a land reclamation concept consisting of lime stabilization of suitable in-situ soft materials was implemented. A combination of sheetpile bulkheads with tie-backs and soil-filled bags retained the stabilized soil fill. In areas with shallow soft soils, the reclamation involved partial removal of soft soils, whereas in areas with very thick soft soil layers subject to heavy operational loads, unsuitable soils were improved with rigid inclusions in varying patterns. To ensure adequate bearing capacity and global stability for the reclaimed zones, an extensive geo-structural study was undertaken. The studies examined the effects of the operational and seismic loads on the stability of the different fill retaining systems and backfilled zones during and after construction. When constructed, the upland portions of the terminals will provide the needed container and bulk storage needs of the terminals.