Design and Construction of Pile Foundations in the Congested Part of Old Dhaka City of Bangladesh - Case Study on Mayor Mohammad Hanif Flyover-Paper

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The Mayor Mohammad Hanif Flyover is a 10.6 km elevated corridor in Old Dhaka, Bangladesh, comprising a 4.8 km main flyover and 11 ramps. Built to relieve severe congestion between Jatrabari and Gulistan, it crosses a densely developed area containing numerous water, sewer, gas, electricity, and telecommunications utilities.<br /><br />Its foundations comprise 2,366 cast-in-place bored piles across 315 substructure groups. Most piles are 1.2 m in diameter and 16.25–37.25 m long; smaller diameters were used where space was restricted. Because major utilities generally could not be relocated, each pile group and cap required site-specific design. The team used a three-stage process: cross-trenching to identify utilities, hand-dug pits to confirm pile positions, and further design adjustments where obstructions were found. This approach enabled construction while largely preserving utilities and avoiding major damage.<br /><br />Foundation design followed AASHTO LRFD 2007, supplemented by other standards. It addressed vertical, lateral, and uplift capacity, pile-group effects, groundwater, and negative skin friction. Geotechnical investigations included 102 boreholes, while pile capacities and integrity were checked using static and dynamic load tests.<br /><br />Three hydraulic drilling rigs installed the piles. C30 ready-mix concrete was placed by tremie, with permanent liners used where needed. Construction records, bore-bottom checks, and other quality-control procedures supported installation in challenging ground and confined work areas.<br /><br />The project required additional time, resources, and cost, and some pile caps had to be raised or enlarged, constraining road space and complicating utility maintenance. Nevertheless, the flyover opened in 2013, separating long-distance from local traffic and substantially improving travel times; the Jatrabari–Gulistan journey reportedly fell to about five minutes.

Keywords

Mayor Mohammad Hanif Flyover

Old Dhaka

Bangladesh

elevated corridor

Jatrabari

Gulistan

bored piles

utility relocation

foundation design

traffic congestion