In freezing process method, area surrounding excavation is frozen and thus a solid wall of frozen Earth is formed. The principle of ground freezing is use of refrigeration to convert in-situ pore water to Ice.

Reinforced cement concrete has more weight and refore it creates difficulties in handling and floating Caisson in early stage of construction. Therefore it becomes economical to construct a Steel Caisson with concrete filling.

The freezing is a powerful versatile tool for foundation engineering for temporary ground support, groundwater control and structural underpinning. A portion of slope is frozen and this position act as a temporary Dam to support soil and it prevents earth slides.

Cellular cofferdam consists of diaphragm cells or circular cells or modified circular cells or cloverleaf cells. In case of circular cofferdams with diaphragm cells, series of arcs are connected to straight cross wall. The radius of arcs is generally made equal to distance between cross-walls.

In case of extremely loose and soft ground which requires immediate support as excavation progresses, arrangement of Runner as shown in above given figure is adopted.

The materials commonly employed for construction of dike are earth, rock and sand bags. The dike are generally employed for a short duration, particularly to enable construction of a more durable cofferdam behind m.

In case of multistage system of well points, deep well pumps should be used when instability of side slopes is expected. As deep well pumps are expensive, y are adopted on important works.

To determine Static formulas, samples of soils through which piles are to be driven are tested in laboratory and properties of different soils are studied in detail. These results from laboratory tests are n used to determine bearing capacity of a pile of a given length, shape and size.

Above given Eytelwein formula is for drop hammers.
Where, R1 = safe load on a pile in kg.
S = final settlement of pile in centimetre.
Eytelwein formula assumes of a factor of safety of 6.

A Well Point is a pipe about 1 m long and diameter is about 40 mm to 50 mm. The whole system comprises of a Riser, swinger arm, header and toger work as a well point system.