Ways to develop methods of determining permeability of nonsaturated soils

1. To determine the impermeability of unsaturated soils to water in hydrotechnical construction, calculation methods based on consideration of the number and size of water-conducting channels with consideration of the regularities established theoretically and experimentally can be used in preliminary stages. 2. It is advisable to use field methods for a more reliable evaluation of the water permeability of unsaturated soils. 3. Along with hydraulic testing, methods of air testing wells and pits should be used widely. The reliability of the results of air testing has been established theoretically and experimentally. 4. The experience of surveys for hydrotechnical construction in the USSR showed the effectiveness of the given methods of determining the water permeability of unsaturated soils.