been built by Hyundai Engineering and Construction (Korea) as a 'design and build' contract. TY Lin Assoc. of San Francisco carried out the design as a sub-contractor for Hyundai. The approach roads were constructed by Samwhan Corporation (Korea). Specifications Sub-structure The bridge is supported on tubular steel piles, driven into the river bed. Sand was removed from within the piles by airlifting and replaced with concrete. Out of the 50 piers, 21 piers are supported on groups of three piles (each of 2.5 m diameter) and 29 piers on groups of two piles (each of 3.15 diameter). The driving of 121 piles started on October 15, 1995, and was completed in July 1996. The pier stems are founded on concrete pilecaps, whose shells were precast and infilled with in-situ reinforced concrete. The reinforced concrete pier stems support pierheads which contain bearings and seismic devices. These allow movement of the deck under normal loading conditions but lock in the event of an earthquake to limit overall seismic loads through the structure and minimise damage. Superstructure The main bridge deck is a multi-span precast prestressed concrete segmental structure, constructed by the balanced cantilever method. Each cantilever has 12 segments (each 4 m long), joined to a pierhead unit (2 m long) at each pier and by an in-situ stitch at mid span. The deck is internally prestressed and of single box section. The depth of the box varies between 6.5 metres at the piers to 3.25 metres at mid-span. An expansion joint is provided every 7 spans by means of a hinge segment at approximately quarter span. The segments were precast and erected using a two-span erection gantry. Gauge The Bangabandhu Bridge carries a dual broad and metre gauge railway track. It also carries pylons for a powerline. The extension of the bridge costed 134 million$ extra later on. Litigation Within a decade of inauguration, cracks were detected on the bridge prompting the authorities to impose limits on the number of vehicles allowed to cross at any given time. By early 2008, the government announced its intention to sue the South Korean conglomerate Hyundai for flawed design. Repair, strengthening and health monitoring During March 2006-June 2006, Bangladesh University of Engineering and Technology experts worked to identify the causes of extensive cracking of prestressed concrete deck, web and pear head units of almost all segments of the Bridge. The cracks were identified primarily