ISO2531 Standard Jacked Pipe Ductile Iron Wear Resistant For Steam Supply
OVERVIEW
This kind of pipe is able to bear huge jacking pressure. As well owns enough intensity to endure
internal and external pressure. It also possesses perect characteristic of anti-corrosion and durability. In addition, the inherent flexibility enables it to adapt ground displacement.
Pipe jacking is a trenchless method of new pipe installation Factory made pipe sections are jacked or pushed behind the tunnel boring machine or other tunnel excavation methods. Jacking force is transmitted from thrust wall installed in the drive shaft. Pipe jacking is used for the following cases.
1.Heavy traffic roads and crossing s of railways, rivers, and massive structures
2.Sensitive environment & neighborhood
The followings need to be considered when jacking is adopted.
1 High water table and difficult soil condition may require special work
2 Jacked pipe may subside in soft ground.
3 H andling unexpected subsurface obstacles may face difficulties while jacking
4 Experience d operators and well organized construction work are necessary.
5 Location of shafts is important . Drive shaft may affect surrounding grounds.
Earth Pressure Balance
In closed earth pressure balance shield jacking, separation wall is placed behind the cutter head of boring machine. Excavated soil with or without plasticizer is filled between separation wall and excavation face to stabilize the face. By controlling the amount of excavated soil removed from the tunnel face, excavation and jacking are operated.