1967pradyot
Geotechnical
- Apr 9, 2003
- 22
I have a problem in hand for which I wish to hear a solution from our experts.
The structure is a monolithic river bridge. The foundation proposed is 1.5m bored cast-in-situ pile of around 30.0m deep. The sub-soil in general consists of alternate layer of sand and clay.The top layer is 10.0-11.0m thick sand, followed by 3.0-4.0m thick silty clay. Silty sand of 4.0 - 5.0m thick is underlain to silty clay. Below which 8.0-10m thick stiff clay and 4.0-5.0m thick silty coarse sand. Foundation tip is in silty coarse sand. Use of Bentonite is not permitted.
I would like to know whether this pile can be bored without permanent casing? If so, how? If temporary casing of 30m is used, how to extract it without using vibrohammer. Or, any other suitable method which can stabilise the hole without casing. Geomud is used but of no use. If you have any earlier experiences please share the same.
Thanks
The structure is a monolithic river bridge. The foundation proposed is 1.5m bored cast-in-situ pile of around 30.0m deep. The sub-soil in general consists of alternate layer of sand and clay.The top layer is 10.0-11.0m thick sand, followed by 3.0-4.0m thick silty clay. Silty sand of 4.0 - 5.0m thick is underlain to silty clay. Below which 8.0-10m thick stiff clay and 4.0-5.0m thick silty coarse sand. Foundation tip is in silty coarse sand. Use of Bentonite is not permitted.
I would like to know whether this pile can be bored without permanent casing? If so, how? If temporary casing of 30m is used, how to extract it without using vibrohammer. Or, any other suitable method which can stabilise the hole without casing. Geomud is used but of no use. If you have any earlier experiences please share the same.
Thanks