Malé-Thilafushi Bridge Project

The Malé-Thilafushi Bridge project, a $500M initiative backed by India, aims to connect Malé, the capital of the Maldives, to the islands of Villingli, Gulhifalhu, and Thilafushi. This ambitious project is the largest infrastructure endeavor in the Maldives' history, with 6.74 km of bridges and viaducts and 210,000 cubic meters of reclaimed land. Module-3, 4, 12 & 17, are three-span bridges comprised of precast segmental post-tensioned concrete box girder continuous superstructures that are integrally connected to the piers. We conducted the detailed design for Module 17 bridge and transverse analysis for the other navigation bridges.

The Module17 bridge is a 337m long bridge with a span arrangement of 96m - 148m - 93m. Its 25m wide precast box girder has a depth varying from 8.5m at main piers to 4.0m at mid-span and ends. The 4m long typical segments, cast using the long-line method, weigh about 215MT, reduced to 2.5m length near supports. In executing such a deep box girder segment, careful attention was given to reinforcement detailing to facilitate easier reinforcement placement and concreting.

Main piers are supported by six 2.5m bored piles, and transition piers by four 2.0m piles. Influenced by wind loads and marine actions, the design accounts for long unsupported pile lengths of 35m-57m due to high scour.  Our team actively participated in technical discussions and helped establish a comprehensive design approach, which included rigorous checks during service and construction stages. L-Pile was used to optimize the foundation design and accurately capture group effects, producing PY curves for scour conditions. The piles were thoroughly assessed for intermediate construction stages during balanced cantilevering before closure.