Pressure distribution under CFA rig
Pressure distribution under CFA rig
(OP)
Could someone provide information (or an internet link) on pressure distribution under a CFA (continuous flight auger) rig. Is the rig ballanced (i.e. exerting uniform pressure on the foundation soil) or is an eccentric pressure distribution within the foundation soil more appropriate. In the later case one would assume the manufacturer should have relevant information on eccentricity...
Thanks in advance for any information.
Thanks in advance for any information.





RE: Pressure distribution under CFA rig
RE: Pressure distribution under CFA rig
It is likely that my question is more appropriate for the rig manufacturers (could someone provide reference?) but I hoped that someone in the geotechnical community may be able to provide some insight....
RE: Pressure distribution under CFA rig
Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora.
RE: Pressure distribution under CFA rig
http://www.hjb.co.kr/equip_g/drill/supply/casagrande/b110b120.htm
More info is required including out-rigger arrangements, up-lift capacity, etc. Your best bet is to contact the actual contractor for details.
RE: Pressure distribution under CFA rig
Focht3: this question came up on a meeting due to some concerns with weak clay seams and burried services - I realized that I am not fully aware what the actual/working stresses in the subsoil are underneath a heavy rig - hence my posting....
In the meantime, I understand that some contractors use the front half (or the back half - depending where the mast is) of the tracks as an effective loading area, with uniformly distributed pressure underneath to account for non-uniform loading.
RE: Pressure distribution under CFA rig
RE: Pressure distribution under CFA rig
The thickness of a working platform is generally not calculated but chosen using rules of thumb between 30cm and up to 1 meter !This should be left to the contractor.
RE: Pressure distribution under CFA rig
Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora.