In press-in piling, how can driving shoes help to reduce jacking loads?

Press-in piling involves the use of hydraulic rams to provide the force to jack the pile into ground. The hydraulic ram is part of machine called “Silent Piler” which uses jacked pile to provide reaction force for jacking.

The use of driving shoes could reduce the jacking load. The presence of driving shoes change the flow of soils around pile tip and this leads to reduced effective horizontal stress on internal pile shaft. As a result, this enhances a reduction in shaft friction which is the major element for making up the jacking load.

This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.