| Construction details | High-density slurry type pipe jacking method with compatible type for underground obstruction |
|---|---|
| Method | Milling mole method |
| Completion date | May. 2014 |
| Location of Construction | Nishinari-ku, Osaka city, Osaka |
| Ordering party | Osaka City Waterworks Bureau |
| Pipe diameter | φ1000㎜ |
| Distance | L=411.6m |
| Type of soil | Sandy soil, Cohesive soil |
| Gravel size |
| Nominal diameter | φ1000mm |
|---|---|
| Distance of pipe jacking | 411.65m |
| Type of soil | Sandy soil, Cohesive soil |
| N value | 10 |
| Percentage of gravel | - |
| Maximum gravel size | - |
| Groundwater level | GL-1.32m |
| Overburden | 8.89ｍ |
| Underground obstacles | Steel sheet pile (typeⅢ) 1 place |
| Construction period | Day and night work (8.0h) Feb. 2014～May 2014 (4.0 months) |
About 161 m after launching, the first obstacle (Steel sheet pile type III) was cut. After that, normal pipe jacking was carried out for 7 m.
The second obstacle (Steel sheet pile type III) was cut & the remaining 244m was reached by normal pipe jacking.
In the section of about 9m across the national road, pipe jacking was carried out while chemical grouting in the TBM.
This work was a water pipe laying work, in which a φ800 mm water pipe was inserted after penetrating the φ1000 jacking pipe.
As a result of the construction, there was no metal reaction at the first obstacle (Steel sheet pile type III), & there was no actual discharge of metal pieces.
We proceeded with the pipe jacking while chemical grouting in the TBM, confirmed the metal reaction of the second obstacle (Steel sheet pile type III), started cutting the obstacle, & checked the discharge of steel pieces.
Check cutting powder (steel piece) with a magnet
Check cutting powder (steel piece) with a magnet
Status of chemical grouting in TBM
