Permafrost or permanently frozen ground is a widespread phenomenon in the northern hemisphere. About one-fifth of all land area of the world is underlain by permafrost.

Wherever present, permafrost affects in one way or another (or is itself affected by) every field of human endeavor. The consideration of permafrost is vital in planning transportation routes, settlements, pipelines, drilling operations, etc. Roads, railroads, and buildings, inappropriately located or improperly designed and built, are likely to be damaged and rendered useless. Drilling tools may freeze in the hole, causing the abandonment of a project. In the permafrost area, the problem of water supply claims foremost attention.

Stresses that develop in freezing ground may exceed 2,000 kilograms per square centimeter. Just as the Russians have done in the past, we are learning, in the hard way, that it is uneconomical if not futile to "fight" the natural forces of frost by using stronger materials, more rigid designs, or to resort to periodic and costly repairs, which rarely if ever succeed in a permanent righting of the situation. Successful solution of permafrost problems depends on a thorough understanding and correct quantitative evaluation of the component elements and on the planning of the project in such a way that the frost forces are utilized to play into the hand of the engineer and not against it. A thorough and comprehensive survey of the permafrost conditions should therefore constitute a prelim nary and an integral part of any engineering project.

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