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Pile Design and Construction Practice, Fifth edition

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Chapter 3<br />

Piling equipment <strong>and</strong> methods<br />

There was a world-wide increase in the construction of heavy foundations in the period from<br />

1950 to the 1970s as a result of developments in high office buildings, heavy industrial<br />

plants <strong>and</strong> shipyard facilities. The same period also brought the major developments of<br />

offshore oilfields. A high proportion of the heavy structures required for all such developments<br />

involved piled foundations, which brought about a great acceleration in the evolution<br />

of piling equipment. There were increases in the size <strong>and</strong> height of piling frames, in the<br />

weight <strong>and</strong> efficiency of hammers, <strong>and</strong> in the capacity of drilling machines to install piles<br />

of ever-increasing diameter <strong>and</strong> length. The development of higher-capacity machines of all<br />

types was accompanied by improvements in their mobility <strong>and</strong> speed of operation.<br />

The development of piling equipment proceeded on different lines in various parts of the<br />

world, depending mainly on the influence of the local ground conditions. In Northern<br />

Europe the precast concrete pile continued to dominate the market <strong>and</strong> this led to the<br />

development of light <strong>and</strong> easily h<strong>and</strong>led piling frames. These were used in conjunction with<br />

self-contained diesel hammers <strong>and</strong> winches, with the minimum of labour <strong>and</strong> without the<br />

need for auxiliary craneage, steam boilers, or air compressors. The stiff clays of the midwestern<br />

states of America <strong>and</strong> the Great Lakes area of Canada favoured large-diameter<br />

bored piles, <strong>and</strong> mobile rotary drilling machines were developed for their installation. In<br />

contrast, the presence of hard rock at no great depth in the New York area favoured the<br />

continuing development of the relatively slender shell piles driven by an internal m<strong>and</strong>rel.<br />

The growth of the offshore oil industry in many parts of the world necessitated the development<br />

of an entirely new range of very heavy single-acting steam <strong>and</strong> hydraulically powered<br />

hammers designed for driving large-diameter steel piles, guided by tubular-jacket structures.<br />

In the present day, the increasing attention which is being given to noise abatement is<br />

influencing the design of pile hammers <strong>and</strong> the trend towards forms of pile that are installed<br />

by drilling methods rather than by hammering them into the ground.<br />

Great Britain has a wide variety of soil types <strong>and</strong> the tendency has been to adopt a range<br />

of piling equipment selected from the best types developed in other parts of the world for<br />

their suitability for the soil conditions in any particular region.<br />

With the advances in the techniques of installing large-diameter bored piles, <strong>and</strong> the<br />

increasing acceptance of these types for the foundations of heavy structures, it did appear at<br />

one stage that the capability of the bored pile to carry very heavy loads would outstrip that<br />

of the driven pile. However, with the stimulus provided by the construction of marine<br />

facilities for large tankers <strong>and</strong> deep-water oil-production platforms, the driven type of pile<br />

can now be installed in very large diameters that approach <strong>and</strong> in some cases exceed those<br />

of the larger bored piles. <strong>Pile</strong>s are also being used to support heavier loads <strong>and</strong> to deeper

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