By rosebell
Following that on May 16 TBM Florence was halted due to facing hard and abrasive rock that impinged the shield, now thai TBM that is ecavating the Snowy 2.0 headrace tunnel has restarted.
Considering that specialist contractors have been using high-pressure water jetting to remove the rock Since May 21, earlier this month Snowy Hydro reported that TBM Florence had moved forward in small increments several times and the machine remained fully operational.
Snowy 2.0 HydroLinking the underground power station to the upper Tantangara reservoir on the New South Wales pumped hydro project, the 16km headrace tunnel’s digging is up to Florence.
As Snowy delivery team states, due to the further highly variable ground conditions, advancement will continue to vary, particularly as Florence navigates the curve leading to the main tunnel alignment.
Additionally, excavation of the 6km tailrace tunnel that is up to TBM Lady Eileen Hudson has reached halfway in excavating, whereas this machine also had completed the 2.8km main access tunnel to the power station. Th tailrace tunnel is going to connect the underground power station to the lower Talbingo reservoir.
While conveyor belt extension and service modifications have been carried out recently, boring to join the tailrace tunnel with the Talbingo intake excavation can start.
Connecting the underground power station to the headrace tunnel that leads to the upper Tantangara reservoir, excavation of the 1.6km inclined pressure shaft (IPS) continues by TBM Kirsten. Kirsten has installed 14 trial rings in the IPS, using locally manufactured concrete segments designed for the high water pressures that will be experienced in the IPS.
Considering that the shaft’s incline reaches 47%, the Snowy team says tunneling the IPS will be a pioneering engineering challenge.
As one of the largest shafts of its type in the world, digging process of the Marica surge shaft has reached 95m, while mechanical excavation, including rock breakers and excavators, and drill and blast continues.
