ev, L. N. Sinyakov, UDC 627.824.3.065:624.131.7 and V. A. Mel'nikov On-site observations of earth dams and theoretical investigations confirm the possibility of the occurrence of zones with a loading condition under which continuity of the soil watertight element can be disturbed as a result of the effect of tensile forces~ Tension cracking is the most dangerous form of rupture of soil which can disturb the normal operation of the dam or lead to failure. The occurrence of tension cracks is promoted by nonuniform displacements which occur during compaction of the soil and are independent of the interaction of forces between elements of the dam, by the configuration of the canyon, and by the presence of irregularities on the surfaces between the dam and the foundation and canyon walls [i, 2].