relation of tip shape and piles end bearing
relation of tip shape and piles end bearing
(OP)
Please tell me if there is any relation between tip shape of a precast concrete driven pile and its end bearing? if dimension of the section of pile is 400x400mm with a piramid tip, is it suitable to design the tip with a 300mm height piramid? The SPT of soil at the tip is greater than 50.





RE: relation of tip shape and piles end bearing
Respect end bearing I assume the same assumption may be made regardless of the shape of the tip shape, since piles will be driven more or less to same refusal status by the driving machines.
RE: relation of tip shape and piles end bearing
RE: relation of tip shape and piles end bearing
RE: relation of tip shape and piles end bearing
RE: relation of tip shape and piles end bearing
The HP stinger will dictate the end bearing capacity of the driven pile as a unit. The weakest joint is the splice between concrete and steel. This joint will always break first than any portion of pile. Before the tip hits the rock, assuming the pile "runs" during "pushing" thru the soft overlay, there will be a sudden stop in the rate of penetration and hammer will bounce quite a bit. Assuming the tip is still intack (you can lose it like a torpedo) when that big bang of the hammer hit the pile, this is where cracking and spalling occurs. The WEAP and PDA picture showing stresses, energy and the whole shebang will tell you the capacity, stresses and all the good stuff you want to knonw. Pile driving formulas do not tell much but should you elect to use one, the Danish formula will give better results as it is more used often. Stingers are not intended to "seat" piles in rock, they are intended to penetrate intermediate hard pan layers before you get to the desired tip. The design objective is to satisfy required BRG/Tension and lateral capacity/delta of the given pile. There are lots of projects that I got involved where the stingers were eventually cut-off & scrapped.
Roque Engineers
RE: relation of tip shape and piles end bearing
RE: relation of tip shape and piles end bearing
Good thread.
RE: relation of tip shape and piles end bearing
how can i design a pile in expansive soils, economically and safetly ( pls give me a guid lines )..
regards