【Construction Case】TD-375 tunnel boring drilling rig

Project Difficulties

Small conduit grouting effect is very poor

Poor cement slurry penetration effect

How will Anman TD-375 save the day

effectively solve the problem of tunnel grouting?

Please continue to read on!

 

Stratigraphic Situation

 

Location (Province):Yunnan

Location (City):Lincang

Drilling Rig Model: TD-375 Tunneling Drilling Rig

Drilling tool configuration: 89 double drill pipes

Process type: Horizontal rotary spraying

Construction process: Single rotary spraying

 

Stratigraphic situation:

The tunnel surrounding rocks are semi-formed sandstone, semi-formed mudstone, semi-formed sandstone interspersed with mudstone and lignite, etc. The rock quality is soft; it has the characteristics of poor cementation, extremely soft rock quality, large pore space, full water, water loss and dry cracking surrounding rocks with very poor self-stability.

 

 

Construction angle(°):-2

Pile diameter(mm):600

Hole depth(m):10

Construction efficiency(min):230

Pure drilling time(min):90

Pure dismantling time(min):4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Construction Technique

 

TD-375 horizontal rotary spraying supporting:

XPB-90EX high-pressure pump, BZ-8 mixing station set

Construction parameters: 

single weight method, slurry pressure 30MPA, 2.4 single nozzle, rotating speed 18R/min, lifting speed 6-12cm/min (according to the range of adjustment of the site stratum changes), water-cement ratio 0.7-0.8 (later changed to 1.0 due to frequent clogging of the grouting pump). Pile diameter is greater than 600mm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1、Adjusting the position of the hole.

2、Drilling with cement slurry, the first two meters of fast entry, slurry pressure of 5MPa. subsequent drilling with 10MPa uniform speed, and always pay attention to the orifice back to the slurry situation and rotary pressure.

3、Drilling to the bottom of the hole according to the initial data operation, see the orifice return slurry situation to adjust the speed, such as the emergence of part of the continuous non-return slurry re-spray, until the return of slurry.

4、Drill rod lifting pre to the hole remaining 0.5 meters in advance to prepare the blockage, the two sides with rapid plugging of the hole. Above using the spacer pile method, back to the pile after 12 must return to the pile, the purpose of reducing pile damage to increase the pile and pile occlusion.

——Anman drilling rig sales service: Fu mingliang