【Construction case】SJ-25A rotary jet drilling rig

Stratum situation

 

Location (province): Guangxi

Location (city): Fangchenggang

Drg model: SJ-25A

Drill configuration: 60 double spin drill rod

Process type: rotary spray reinforcement

Construction technology: double rotary spray

Stratigraphic condition: sediment at the bottom of rotary excavation pile hole

Construction Angle (°): 90

Hole depth (m): 32

 

 

Construction technology

 

Construction technology of high-pressure rotary spray treatment of pile foundation defects

 

Configuration:

 

1 SJ-25A high pressure rotary injection drill, 1 GPB-90 high pressure grouting pump, 15.0 cubic air compressor, 162 m 60 double rotary injection drill rods, 1 double pipe drill with nozzle, 2 cement slurry mixing drums, 1 clear bucket, high pressure grouting hose, compressed air hose (meters as required)

 

1、determine the number of holes according to the pile diameter;

 

2、The high-pressure rotary jet drill will put the drill pipe bit down to the defective section for high-pressure water repeated washing and cutting, and the compressed gas will return the cutting residue from the hole out of the hole;

 

3、The new building material-prestressed channel grouting is mixed evenly according to the standard, the pressure is 18MPa, the lifting speed is 10cm / min, the rotation speed is 15r / min, and the defect section is rotary jet grouting twice;

 

4、After the completion of grouting, seal the solid hole with a new building material- -bearing mortar.