Umbrella Steel Pipe Roofing
In recent years, the application of umbrella steel pipe roofing method as long distance fore-pile has become a standard auxiliary method in tunneling projects. The special drill tools (NATMTECH drill system) make it possible to use the same drill jumble on site for the pipes’ installation, which brings greater convenience for the contractors.
In the aforementioned method, rigid steel pipes are installed toward the tunnel’s longitudinal direction to form an umbrella pipe group and then injected with cement or urethane series grout to form a pre-supporting roof. The resulting grout consolidation doubles the support effect of the pipe group with its surrounding geology. This is why the resin grout or micro fine cement grout with better penetration and shorter gel time is more preferable by tunnel engineers.
In the aforementioned method, rigid steel pipes are installed toward the tunnel’s longitudinal direction to form an umbrella pipe group and then injected with cement or urethane series grout to form a pre-supporting roof. The resulting grout consolidation doubles the support effect of the pipe group with its surrounding geology. This is why the resin grout or micro fine cement grout with better penetration and shorter gel time is more preferable by tunnel engineers.
Features
Specification
EN standards from S235 ~S355
ASTM A53 Grade B
JIS G3444 STK 400 and 500
CNS 2056 G3030 heavy duty
ASTM A53 Grade B
JIS G3444 STK 400 and 500
CNS 2056 G3030 heavy duty
A.Installation by the same drill jumble on site. Thus, no special drill machines or personnel are required.
B.Working process conforms to the tunneling cycle time.
C.The NATMTECH drill system, composed of simple and robust drill tools, leads the steel pipes step by step into the borehole.
D.Drilling and installing the steel pipes simultaneously minimizes the impact from interruptions by the surroundings.
B.Working process conforms to the tunneling cycle time.
C.The NATMTECH drill system, composed of simple and robust drill tools, leads the steel pipes step by step into the borehole.
D.Drilling and installing the steel pipes simultaneously minimizes the impact from interruptions by the surroundings.
Diameters are ranged from
2.0” O.D. 60.5 mm
2.5” O.D. 76.3 mm (general choice)
3.0” O.D. 89.0 mm
3.5” O.D. 101 mm
4.0” O.D. 114.3 mm (general choice)
5.0” O.D. 139.7 mm
The efficient installation length is generally 12m or above. However, longer installation depth may be required depending on different geology conditions.
2.0” O.D. 60.5 mm
2.5” O.D. 76.3 mm (general choice)
3.0” O.D. 89.0 mm
3.5” O.D. 101 mm
4.0” O.D. 114.3 mm (general choice)
5.0” O.D. 139.7 mm
The efficient installation length is generally 12m or above. However, longer installation depth may be required depending on different geology conditions.
