We have a 1.5 to 1.7m diameter caissons to be drilled into approximately 10 m of soft clay and 12 m of Queenston shale with an RQD of 28 to 35 %. Can Kobelco Rig or Link-Belt Rig do the job?
Not sure why you would question if such rigs can do the job. Clay and a RQD of 28% is pretty mundane stuff. In fact, I don't know if you can call 28% quality real rock!
Regards,
Qshake
Eng-Tips Forums:Real Solutions for Real Problems Really Quick.
I remember drilling solid stem augers during site investigations some 15 feet or so into the weathered Queenston Shale - but for other's information, the shale also contains small bandings (say 4 to 6 inches thick) of limey-shale as well. It is a bit harder. Qshake is right - any "big" rig should be able to socket into this material without much problem. Again, several of the Toronto-area drilled shaft contractors would be more knowledgeable.
Thanks all for the inputs. We did contact some drilling contractors. They thought they can drill into whethered shale, top 5-6m below caly, but not into sound shale , bottom 6m of the caisson.
The rigs are mounted on cranes with 2 kelly bars.
Might be so - but your RQD values were pretty low - even in what you are calling sound shale now (not supported by the RQD). They could probably star drill pretty quickly through the shale if you need to make socket. Otherwise - why not use a belled caisson (assuming that your problem is bearing).
BigH it apparently happens on the last entry of the thread. For example your present post (17 Mar 08 at 13:32) has "Foundation Design Program" and "Construction Engineering" links.
Regards,
Qshake
Eng-Tips Forums:Real Solutions for Real Problems Really Quick.
Qshake, I don't see any notes or links on any of BigH's responses.
BigH's last response said only the following: "Might be so - but your RQD values were pretty low - even in what you are calling sound shale now (not supported by the RQD). They could probably star drill pretty quickly through the shale if you need to make socket. Otherwise - why not use a belled caisson (assuming that your problem is bearing)."
I figured it out. Every other post has a white background and so does the bottom of the screen. So for the posts that are white it appears as though the adverts are withing the last posts. Those that are purple, the adverts are easily distinguishable as being adverts at the bottom of th page.
Regards,
Qshake
Eng-Tips Forums:Real Solutions for Real Problems Really Quick.
If you look more closely, you will notice that the last "white" posting is actually very slightly shaded with blue. The advert section below the "white" posting is a cleaner white.