The subject matter of this thesis is the study of the mechanical behavior of clay and residual soils subjected to a series of tests with temperatures ranging from 20 to 70ºC. The experimental program consisted of Atterberg limits, consolidation tests with incremental loading (SIC), triaxial consolidated undrained tests (CIU) and direct shear tests on both soil types under saturated conditions. Samples for Atterberg limit tests have been pre-heated in oven to the specified temperature. Heating control and thermal distribution systems have been specially developed for insuring an homogeneous temperature throughout the consolidation, triaxial and direct shear tests. The thermal balance times for the two soils were achieved by means of a calibration method developed for the heating system. Transducers and load cell calibration were carefully calibrated acording to the temperature range for the testing program. It may be concluded that pre-heating to temperatures below 70ºC has no influence on the Atterberg limits results for both soils. Consolidation tests have shown that heating on samples leads to an increase in compressibility and also on the coefficient of consolidation. From the triaxial tests it was observed that an increase in temperature leads to an increase in strength and to smaller excess porepressures during undrained shear tests. The increase in shear strenght with temperature observed on triaxial tests was also confirmed by direct shear tests. These effects were more significant in clay than in residual soil.