TBM tunnelling works has begun on the 11.8km long tunnel for the Xe-Pian Xe-Namnoy Hydropower Project in Laos. To witness the milestone, a ceremony was arranged and attended by officials from Client, Xe-Pian Xe-Namnoy Power Company, Contractor, SK Engineering & Construction, SELI Overseas, and TBM manufacturer TERRATEC.
The TBM had been previously tested at the TERRATEC factory in December. Since then, it was dismantled, transported to site and re-assembled within approximately three months.
After completion of the site testing, the TBM is now to advance through 500m of tunnel adit constructed by Drill & Blast. Once the TBM reaches the tunnel face, it will commence the boring and installing the segmental lining for the remaining 11.3km of tunnel.
The TBM, a TERRATEC 5.74m dia. Double Shield Hard Rock TBM, will have to excavate through two main formations, the “Tholam Formation” consisting of mudstones and siltstones and the “Champa Formation” including siltstones, sandstones and conglomerates.