Soil strain measurements in areas of underground mining exploitation

The concept of a new method of measuring soil strains induced by underground mining exploitation is proposed. The method and an appropriate apparatus may be applied for long-term, extending for several years, measurements of Infinitezimal and finite strains. Examples of results are given illustrating a local three-dimensional state of strain, expressed as a function of time and a function of a certain situation of an exploitation front with respect to a measurement site. The existence of some relations between a surface deformation and an underground tremor and between strain and the changes in the seismic wave velocity in soil and apparent resistivity has also been shown.