EFFECTS OF BENTONITE ON SKIN FRICTION OF BORED PILES

Bored piles are commonly used to support heavily loaded structures in Malaysia. Bored
piles transfer the applied loads to the ground via skin friction of pile shaft and end
bearing of pile toe. During excavation of borehole, bcntonite is sometimes used to
support the wall of the borehole or to avoid soil collapse in the borehole. This report
studies the effects of bentonite on the skin friction of bored piles. Static load tests were
conducted on five bored piles located on Kuala Lumpur Kenny Hill Formation, where
three of' them were constructed with bentonite and the rest of' them without. The
ultimate pile capacity of each pile is obtained from the load-settlement curves using
Davisson's method. The actual field parameters such as skin friction and end bearing
resistance are then back-calculated using probabilistic inverse method. Comparison is
done between the parameters of' bored piles constructed with and without bentonite.
The result shows a smaller value of skin friction for bored piles constructed with
bentonite compared to the bored piles constructed without bentonite.