The process of wash boring consists in driving an inner tube of diameter 25 mm to 50 mm, inside an outer tube of diameter 100 mm to 150 mm. Whereas, percussion boring and rotary drilling are types of Deep boring.

Zero correction is obtained from load settlement curve. The zero correction should be deducted from observed settlements to get actual settlements.

However, if water table is situated below bearing surface of soil at a depth equal to width of foundation trench, no such reduction should be applied. But in this case, 50% reduction is applied. For intermediate depths of water table, proportion and percentage reduction should be applied.

Test Pit is excavated up to a depth about 1.50 m at which sufficiently hard soil is available. The various data of soil can be inspected, studied and classified accordingly. This method is useful when hard soil is available within a maximum depth of 1.50 m.

Composite pile is formed when it is a combination eir of a bored pile and driven Pile or of driven piles of two different materials. In this combination, advantage is taken of durability of concrete piles and cheapness of timber piles.

It is normally used in soft inorganic soils. Stone columns are essentially a method of soil reinforcement in which soft cohesive soil is replaced at discrete points by compacted stone or crushed rock in pre bored vertical hole to form columns or files within soil.

Plate load test method is one of methods of determination of bearing power of soil. Plate load test method is improved point method and it is widely used for determination of bearing capacity. Or methods for determination are method of loading, method of dropping weight, analytical methods and Presumptive method.

The bottom of timber sheet pile is chamfered so as to form a cutting edge and if necessary, both top and bottom are provided with suitable iron fittings. They usually consist of wooden boards 80 mm to 150 mm thick, 200 mm to 300 mm wide and 2 m to 4 m long.

This method is based on principle that each soil has different electrical resistivity, depending upon its water content, compaction and composition. For instance, saturated soil will have lower electrical resistivity as compared to loose dry gravel or solid rock.

The number of banks full of sand or arrange on rolled Steel section. The sand bag is on platform till settlement of ground ceases or stops. The loading should be applied without shock or impact at centre.