1. For Pile in clay strata which is subjected to shrinkage settlement


2. Lower of ground table causes settlement of ground causing negative skin friction.


3. Fill ground undergoes consolidation which causes negative skin friction.


4. Negative skin friction develops if soil sets re-moulded or disturbed due to the pile installation


5. If pile is installed in clayey soil with surcharge loading, negative skin friction may develop.

Whenever there is a chance of settlement of soil and clay soft layer is encountered, negative skin friction may get developed. It is required to take special care whenever there is a chance of development of negative skin friction.

Pile Driving Equipments
Pre-cast pile driving equipments consist of -

1. Pile frame


2. Pile hammer


3. Helmet


4. Follower