| 摘 要： | Radioisotope S^35 carried by Na2SO4 solution is a. good tracer for studying watersalt movement in soil layer. Examination of radioisotope S^35 as a tracer for the water-salt movement has been performed in laboratory by making use of simulated soil columns as well as in an experimental highway subgrade. The results indicate: (1)the maximum penetrating depth of atmospheric precepitatious in some arid regions in Northwestern China is about 20--30 centimeters; (2) an excess of water for construction usage for example, in the range of 30-40 kg/m^2 may probably lead to a upward migration of the salts from lower soil layers into the foundation and consequently cause damage to buildings.
|
