Deep Compaction of Granular Soils

Foundation engineering plays an increasingly important role in social and industrial development, for example in connection with major construction projects such as power stations or the expansion of infrastructure systems (railways, harbors, airports etc.). However, challenging foundation problems can also be encountered on smaller projects, for example when working in the vicinity of sensitive structures or installations. In many countries, limited availability of space, especially in urbanized areas, has led to the need to reclaim land from the sea or to build on ground with marginal or poor foundation conditions. Until recently, most major structures to be constructed on loose, compressible soils were founded on piles or other types of deep foundations. This has been an acceptable but costly solution to most foundation problems. However, soil improvement methods are being used increasingly in many countries, as they can be more cost-effective in many cases and may be adapted more easily to variable ground conditions and design requirements. Therefore, soil improvement methods have been among the most rapidly developing specialty areas of geotechnical engineering over the past 15 years and will continue to do so in the foreseeable future. Soil compaction can be used to improve the geotechnical properties of natural or man-made soil deposits, consisting primarily of granular materials, such as gravel, sand and silt. The objective of the present paper is to discuss the possible applications and limitations of deep compaction methods, to illustrate their practical applications and to outline new developments.