This latest EPB TBM will be used by Gulermak-Sam India JV for Gujarat Metro Rail Corporation Ltd to complete the Phase 1 tunnelling works, which comprise a 7km tunnel and six underground stations. Terratec has also supplied three refurbished TBMs to the project.
The EPBM has a robust mixed-face, dome-style cutterhead designed to work effectively in the soil composed of sand, clay, gravel and silt.
For added versatility, Terratec has designed the cutterheads to allow the cutting tools to be exchanged for 17in (432mm) disc cutters, allowing the EPB TBM to bore through diaphragm walls and cope with unexpected obstacles, such as old wells or foundations.
As the four TBMs progress, they will install 1,500mm x 275mm universal-style pre-cast concrete lining rings, which consist of five segments plus a key.
Work on the Surat Metro, in the western state of Gujarat, began in January 2021 and the project is due to be completed by December 2023. The rapid transit rail system will consist of two corridors with a combined length of 40.35km.
The geological conditions along the tunnel alignments are sand, clay, gravel and silt. A twin bored underground tunnel will be built between the northern ramp and Surat Railway Metro station, and cut and cover will be used for the six underground stations. The work consists of two packages: Package UG-01 covers Kapodra, Labheshwar Chowk and Central Warehouse stations; Package UG-02 covers Chowk Bazar, Maskati Hospital and Surat Railway stations.
In all, Phrase 1 comprises 20 metro stations on the first corridor from Sarthana to Dream City and 18 on the second corridor from Bhesan to Saroli.
