Project Description:
In order to meet the demands from the contractor, Golder Associates AB, sub-contractor PEAB was looking for new drilling technology to reinforce the unique Banco building in Old Town, Stockholm. A total of 400 holes were to be drilled with casing. New piles are then driven down in the cased holes. Pneumatic drilling was ruled out due to danger of damaging the building. Drilling with top hammer or water hammer were the only alternatives.
Result:
After test drilling with Wassara with good results it was decided to introduce the Wassara technology in parallel with traditional top hammer drilling. Towards the end of the project the conclusion was that drilling with Wassara was 2-3 times more efficient compared to top hammer drilling.
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Equipment: |
Hammer |
Wassara W100 |
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Bit |
Ring bit |
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Pump |
WASP |
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Drilling fluid |
Clean water |
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Drill pipe |
1000mmx89mm, pipe thickness 6,3 mm |
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Rig |
Comacchio, rebuilt by Geomek |
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Formation |
Old wood piles, old filling material, clay |