Variable Soil Thermal Resistivity - Steady-State Analysis

The detrimental effects of moisture migration in soils on the ampacity of buried cable systems is an old fact recognized by cable engineers. Yet, no direct method to take this phenomenon into consideration has been available in the past to determine the proper ratings of power cables. The effects of soil moisture content on the variation of the thermal resistivity of the soil are discussed and equations established to determine the effective thermal resistivity when moisture migration has occurred and a final steady state has been reached.