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An introduction to geotechnical engineering / Введение в геотехническую инженерию
Geotechnical engineering is concerned with the application of civil engineering technology to some aspect of the earth, usually the natural materials found on or near the earth's surface. Civil engineers call these materials soil and rock. Soil, in an engineering sense, is the relatively loose agglomerate of mineral and organic materials and sediments found above the bedrock. Soils can be relatively easily broken down into their constituent mineral or organic particles. Rock, on the other hand, has very strong internal cohesive and molecular forces which hold its constituent mineral grains together. This is true for massive bedrock as well as for a piece of gravel found in a clay soil. The dividing line between soil and rock is arbitrary, and many natural materials encountered in engineering practice cannot be easily classified. They may be either a "very soft rock" or a "very hard soil." <...>