Question
What are thought in determining whether casings have to be left in for mini-piles?
Answer
Contrary to most of pile design, design of min-piles is controlled by interior capacity in its place of outside carrying capacity due to their small cross-sectional area.
There are mostly two reasons to account for scheming mini-piles as friction piles-
(i) Because of its high slenderness ratio, a pile of 200mm diameter with 5meter extended has a shaft area of 100 times better than cross-sectional area. Therefore, shaft friction mobilized has to be greater than end resistance.
(ii) Settlements of 10-20 percent of pile diameter are essential to assemble full end bearing capacity, compared with 0.5-1 percent of pile diameter to develop maximum shaft conflict.