Challenge 11

Challenge-11

Ans of question-1

Empirical formula for pile load-

Pile load= [P/n ± (My * X/Sx^2) ± (Mx * Y/Sy^2)]=Tonne

Where, P=Vertical loads on group of piles.

n= No of piles.

Sx^2=Sum of square of distance of all piles in X direction.

Sy^2=Sum of square of distance of all piles in y direction.

My=Longitudinal moment= ton-meter

X= coordinate in longitudinal direction = meter

Y= coordinate in transverse direction = meter

[Note- The distance between one pile to another pile is in the range of 2D to 4D, where D is the dia of pile.]

Ans of question-2

Design philosophies of mono piles-

Monopiles are those types of pile in which we need not to be fixed the pile cap, and a group of pile are not to be required, only one pile is required for one pier.

Monopile

Monopiles are preferred in location where piling is very difficult and multiple pile casting may delay the project. For example, in sea links where sea bed is more than 25 to 30m bellow top of pile or if the sea bed has a hard rocky strata.

Design philosophies of group piles-

Group pile means a group of 4 to 6 no of pile construct bellow the pile cap, if we need lesser pile length as per soil bearing capacity then we construct group piles.

Piles are mainly designed for shear and flexture effects resulting from soil structure interaction with the vertical load of the structure on them. Minimum 4 % reinforcement is allowed as per IS code.

Group pile

Piles have to be properly socketed in rocky strata since the loading is mainly transferred through end bearing and there is a possibility of crushing of pile bottom tip due to such heavy loads.

Lesser spacing is adopted for piles in rocks.

Making the center of gravity of pile group with center of gravity of eccentric load reduces the push/pull load effects in the pile.