Construction Ground Freezing

Abstract

Controlled ground freezing for construction and mining applications has been in use for over a century. Frozen ground may be used to provide ground support, groundwater control, or structural underpinning during construction. Constructed prior to excavation, the frozen earth wall, for practical purposes, eliminates the need for sheeting of the earth, site dewatering, soil stabilization, or concern for movement of adjacent ground. It is a versatile technique that involves use of refrigeration to convert in situ soil pore water into ice. The ice becomes a bonding agent, fusing together adjacent particles of soil or blocks of rock to increase their combined strength and make them impervious to water seepage. Excavation and other work can then proceed safely inside, or next to, the barrier of strong, watertight frozen earth. It should be noted that it is essential that groundwater be present, supplied either by high water table or artificially.