Piles and caissons are structural elements that transfer load from a superstructure (i.e. building) to underlying soils or rock. Pile foundations are used when loads are too high to be supported by footings or mats. Load transferring is provided by "skin" friction between soil and the pile sides and by "end bearing" at the tip. However, pile settlement has to be limited within acceptable levels and may end up controlling the design pile capacity.

Piles and caissons may experience compression, tension, and lateral loads. These loads may be generated by static or dynamic forces (soil pressure, wind, earthquake, etc.). In many cases, pile group interaction has to be considered because closely spaced elements will have smaller capacities.Typical pile loads range from 30 Tons to 250 Tons.

Structuraly, piles can be: a) Concrete cased or uncased, b) Precast-prestressed concrete,c) Timber, d) Steel H or pipe sections, e) Plastic, and f) special systems.

Piles can be driven or drilled in place. Installation method depends on a wide range of factors such as local experience, settlement control, noise levels etc.

Caisson foundations are typically used when very high loads need to be supported. They are large diameter concrete elements installed with a casing that can be left in place. The caisson bottom can be expanded (i.e. bell bottom) to provide more bearing area or it may include a rock socket where required. Loads in the range of 2500 Tons are not uncommon for caissons.

Deep Excavation LLC can provide design services for your foundation project. We can also provide construction services through our affiliated contractors. Please contact us for further assistance.