TERRATEC announced the completion of Samui Island Water Tunnel Project in Thailand. The tunnel was completed using a refurbished TERRATEC 3.2-m diameter Earth Pressure Balance Tunnel Boring Machine (EPBM) by contractor SCG (1995) Co. Ltd.
The project owner, Department of Public Work and Town & Country Planning Authority, contracted SCG (1995) Co. Ltd. to construct a 1.1km long tunnel for the Samui Island flood control system. The tunnel is designed to alleviate flooding and to drain the flood water on Samui Island from busy areas to the ocean.
Samui Island is an island off the east coast of Thailand and it is Thailand’s second largest island after Phuket. Each year, there are more than 2.7 million tourists. The island faces severe flood problems and the tunnel is intended to ease the flood water. Being part of the main Ring Road revitalization and improvement project, the water tunnel will significantly improve the rainwater collection from roadway run-off along Samui’s main ring road.
Featuring a classic soft ground open spoke cutterhead design, with knife bits to assist break-in and break-out of the steel fiber reinforced concrete shaft eyes, the EPB coped extremely well with the geological conditions along the alignment, which consist of dense sand, stiff to hard clay and decomposed rocks with a groundwater head of about 2 bars.
The receiving shaft, sized in 5 x 9 m, is located at the bottom of two hills where the flood occurs. The flood water will be drained through the new tunnel and connected with a 500-m open canal to the ocean. With TERRATEC’s non-tuck hose system, muck can be easily transferred to muck cars and out to the surface.
Machine operation was assisted at all times by TERRATEC’s experienced Field Service staff, providing quality after-sales support to ensure optimum performance and successful project completion. Tunneling operations were closely observed throughout the maneuver via a settlement monitoring program.
Prior to the Samui Island Water Tunnel project, the 3.20-m diameter TERRATEC S48 Earth Pressure Balance Tunnel Boring Machine (EPBM) was operated for Bangkok Metropolitan Electricity Authority’s (MEA) Phra Khanong Cable Tunnel Project in Bangkok, Thailand. The machine was operated by Thai contractor Nawarat Patanakarn PCL to excavate a sharp 32-m radius curve as it exited the project’s launch shaft in order to negotiate the piles of an adjacent expressway ramp.
To achieve this challenging curved alignment, the TERRATEC machine was manufactured with an extreme X-type articulation system that provided a maximum articulation angle of 6.6 degrees. Designed to accommodate a new high-voltage cable system, the Phra Khanong Cable Tunnel Project was the first of a series of planned tunneling projects by the MEA that were being built to meet increased power demands in the Thai capital.
TERRATEC has a well-established regional base in Thailand, having sold its first machine in the country more than 10 years ago for the Metropolitan Rapid Transit (MRT) Blue Line Extension Project. With outstanding tailor-made robust TBM design, prompt onsite assistance, readily available stock of TBM spares and specialized TBM support throughout the tunneling operation, TERRATEC has become the country’s leading TBM supplier.