expansive soils, problems and remedies

Expansive soils problems have received the attention of researchersand engineers in the field of Soil Mechanics and Foundation Engineeringover a period of many years in many countries all over the world. Sinceproblems with such soils have been associated with particular geographicareas and climates, and are inherently of a complicated nature, engineer-ing solutions have tended to be empirical. Only in recent years havetheoretical and experimental approaches been developed which promise toprovide a more thorough basis for understanding the basic phenomenainvolved and for developing sound design criteria.The specific behavior of the expansive soils and their dangerouseffect on structures was recognized and studied first by Kar1 Terzaghiin 1930. He observed the differential swelling of the soils whichcaused damages to a building in Texas. Since that time, the amount ofdamage caused by expansive soils to buildings, houses, highways andunderground utilities, led to several studies to overcome these problems.To imagine the size of the problem, it has been estimated that theexpansive soils cause more damage than earthquake, tornados, hurricanesand floods combined in the United States.Expansive soils problem represents a widewor1d problem, tending tobe concentrated in the arid and semi-arid areas. Expansive soils coverone-fourth of the United States, in Texas northward through Oklahoma,