Methods of pile installation

Question

What are the various methods of installation of piles in a construction?

Answer 1

Methods of installation:

The various methods used for the installation of the piles are:

Dropping weights:

It is the most widely used method of inserting the pile in the desired foundation. It is also known as drop hammer. The weight is raised up to a suitable distance above the ground and then it is allowed to strike back on to the ground and hit the pile head. The weight can be up to half of the actual weight of the pile.

Diesel Hammer:

Diesel hammer can be used to produce to carry out rapid controlled explosion. In order to drive the pile in to the ground a ram is raised by the explosions. Although the ram is smaller than the weight used in the drop hammer the increased frequency of the blows can make up for this inefficiency. This type of hammer is most suitable for driving piles through non-cohesive granular soils where the majority of the resistance is from end bearing.

Jacking methods of insertion:

In underpinning existing structures the jacked piles are most suitable. By using the underside of the structure as a reaction the short length piles can be easily inserted in to the ground.

Vibratory methods of pile driving:

When there is a requirement of driving the piles in non cohesive granular soils, the vibratory methods prove to be more efficient and economical. Due to the vibration of the pile the soil grains which are present adjacent to the pile gets excited and thus make the soil almost free flowing. Due to this the friction existing near the pile shaft is reduced. The vibration can be produced by electrically, hydraulically powered contra-rotating eccentric masses attached to the pile head usually acting at a frequency of about 20-40 Hz. In moderately dense granular soil if the frequency of the machine is increased to 100 Hz then a longitudinal resonance can be gained and thus the speed of penetrating the pile inside the soil can go up to 20m/min.

But the biggest problem is that sometime the equipment may get damaged due to the vibration. Also vibration and noise propagation may be harmful for the settlement of any nearby construction.