This D&B project was awarded to Hyundai Engineering & Construction and consists of 1 km of 1m diameter foul sewer, 5km of 3.0m and 2.4m diameter utility service tunnels and storm water tunnels. The tunnels were constructed as part of the 12km Lusail Expressway which will link the heart of Doha with the north of the city. The utility service tunnels and storm water tunnels required the construction of fifteen 7.5m diameter permanent shafts, constructed within 11m diameter temporary secant pile shafts.
Our role included the selection of the tunnel alignment and shaft locations, design of all permanent and temporary shafts, designs associated with all tunnel and shaft linings, cable supports, ventilation system, drainage, heat detection, alarms, lighting, security and low voltage power supply. This included obtaining design and construction approval from Ashghal, Civil Defence and Kahramaa approval. The role included the geotechnical instrumentation and monitoring plans to ensure tunnelling and diaphragm wall movements and ground movement assessments met design risk assessments, trigger levels, and dewatering targets.