Ma’ameer Culvert Tunnelling Project

Approach

We used two of our own Iseki TCC 1200 machines with a third setup for jacking the rig, so that when one tunnel was complete, the next machine was in place and ready to start on the same day thanks to the advanced setup put in place.  The level and line were maintained perfectly.

Access to our data logging system was also given to consultants SSH to monitor the targets in real time.

The approach also involved marking settlement points all over the road and utilities with checks taking place every three days – resulting in no settlement.  It was critical to grout after each tunnel was complete including the annulus between the pipes and the ground with cement.

Scope

Joseph Gallagher Middle East was appointed to install 12 x 1200 internal-diameter tunnels under one of the busiest carriageways in Bahrain connecting the water bodies on either side whilst maintaining the flow and preventing any stagnation.

It was considered a VIP project with daily updates requested from the Prime Minister and Minister of Works.

The single biggest challenge encountered was the crossing of a huge number of utilities and the existing culvert in 12 parallel lines. These were gas lines, water lines, electric cables, fibre-optic cables, communications cables coupled by, the works taking place beneath one of Bahrain’s busiest carriageways. However, having the right approach to complete this work resulted in the works being completed ahead of schedule and to excellent standard.

Added Value 

Community Involvement - a number of engineering students from the University of Bahrain visited the site to learn about microtunnelling methods and see the Iseki machinery in action.

Project Highlights

• Record installation times achieved
• Two of our Iseki microtunnelling machines were used simultaneously with the sequence of installation designed to minimise any potential settlement
• Average production, including setup and relocation, exceeded 37m in 12-hour-shift with each tunnel being 120m long
• Programme delivery was anticipated at 104 days - the JGL team delivered the works in 40 days, with an average number of 25 operatives working across both shifts.