The Snowy 2.0 Hydro Project has reached another milestone with the second tunnel excavation now completed at Lobs Hole in New South Wales.
The 2.93 kilometre emergency, cable and ventilation tunnel (ECVT) has been excavated and fully lined with 13,140 concrete segments by tunnel boring machine (TBM) Kirsten.
Snowy Hydro 2.0 chief executive officer Dennis Barnes said the projoect is progressing well, despite recent geological challenges.
“We are extremely pleased the ECVT excavation has been completed and the whole project team is excited to be moving into the next critical phase of construction,” Barnes said.
“Our huge power station cavern will be located about 800 metres underground and will be one of the largest and deepest in the world.
“We are also using drill and blast methods to construct cross passages linking the ECVT with the MAT.”
TBM Kristen is also being modified to excavate the inclined pressure shaft and line it with locally manufactured concrete segments.
“The shaft is 1.45 km long and excavating a segment lined tunnel of this length at a very steep 47% incline using an 11-metre diameter TBM is without precedent internationally,” Barnes said
The modifications include altering the levels of the TBM’s tanks and mechanical equipment so they remain horizontal when travelling up the incline.
Subscribe to Trenchless Australasia for the latest project and industry news.