March 13, 2015

Provide a suitable founding strata for each of the proposed high rise buildings by adoption of ground improvement techniques in Abu Dhabi.

Project Title

STEP Link Sewers

Location

Abu Dhabi

Country

United Arab Emirates

Client

Abu Dhabi Sewerage Service Company

Business Sectors

Geotechnical Engineering

Services (Technical Disciplines)

• 43km of link sewers
• 300 No. temporary shafts, up to 30m deep
• BLP role Geotechnical Consultant & Temporary Works Designers
• Significant hazards included Cavities and Groundwater Control

Project Objectives/Outcomes

This forward looking US$1.5bn project will transfer wastewater a distance of 40km through a sewer with diameters ranging from 200mm to 2800mm from Saatiyat Island to an area in Al Raha beach involving the construction of over 300 shafts.

Byrne Looby provided engineering design parameters for both the tunnels and shafts, scoped and supervised the additional ground investigations to inform the whole project, provided temporary works designs for the shafts and prepared construction impact assessments. Given that the tunnel passes through a sensitive urban area, monitoring is of critical importance. Byrne Looby prepared the instrumentation and monitoring plans including trigger alert levels.

Our Role

Byrne Looby undertook a risk management strategy including:

• Risk assessments for all shafts/tunnels
• Planned, scoped, tailored & supervised additional Ground Investigations.
• Prepared Ground Model and Geotechnical Interpretation Reports.
• Provision of ground contour plans, construction impact studies and the engineering parameters for the design of the shafts and tunnel.
• Provided Temporary Works Designs for the shafts which were combinations of secant pile walls, shotcrete lining and shotcrete lining with rock bolts.
• Prepared the instrumentation and monitoring plans including the monitoring of ground movements, ground water and ‘trigger’ alert levels.
• Undertook On-site inspections to validate design conditions.

Geoscience Ireland Contact

Michael Looby – MLooby@blpge.com