malcolmwoodruff
Geotechnical
- Feb 4, 2005
- 2
In the UK bottom driven steel tube piles are frequently used for underpinning and small developments. They are normally driven to a set. However, each contractor uses their own pet formula for that set and all formulae that I have come across originate for top driven piles and I have seen no research that looks at losses etc. for bottom driven piles or what dynamic formula might be appropriate.
Furthermore, the piles are frequently used in low headroom situations so come in short sections. The bottom is crimped into a cruciform shape and the top of each section is swaged so that a 215mm od pile becomes 228mm od for a 100mm length every 2m which must affect the skin friction achieved.
Any thoughts on suitable dynamic design formulae, the losses to be taken into account and the effect of the enlargement on the available skin friction would be very welcome.
Furthermore, the piles are frequently used in low headroom situations so come in short sections. The bottom is crimped into a cruciform shape and the top of each section is swaged so that a 215mm od pile becomes 228mm od for a 100mm length every 2m which must affect the skin friction achieved.
Any thoughts on suitable dynamic design formulae, the losses to be taken into account and the effect of the enlargement on the available skin friction would be very welcome.
