|Ductile Iron Cast Iron
|2m, 4m, 3m, 6m
|Grey, Cement Color
|DN600 TO DN1200
|DUCTILE IRON JACKING PIPE
Groundwater Jacking Carbon Steel Tubing Explosionproof With Cement Lining
Selection of Jacking Method
Selection of jacking method needs to consider the following conditions; traffic, drive length, soil & groundwater conditions, sewer line route, diameter, traffic and neighborhoods at shafts, spoil removal and carry-in of pipes at shafts, subsurface obstacles and utilities, aerial power cable. Among them, the most important point is soil and groundwater conditions. The soil and groundwater conditions may require additional ground improvement works such as a chemical grouting. It is difficult to change jacking methods due to inoperable situation once a project begins. Therefore, the right method has to be chosen.
Open Hand Shield
Open hand shield method is mainly used when excavation face is stable with small influence of groundwater. Its system is quite simple. As excavation face is open, obstacles are removed easily. The open hand shield method is often used for short drive length.
In closed slurry shield jacking, the separation wall is placed behind the cutter head of the boring machine. Between separation wall and excavation face, slurry is injected to stabilize the face while keeping excavation smooth. Excavated material is transported from the tunnel face to outside of the shaft as waste slurry. Waste slurry is recycled after treatment at a separation plant.