Soil thermal resistivity and thermal stability measuring instrument. Volume 1. Determination of soil thermal stability and other soil thermal properties. Final report
Numerous considerations influence the thermal design of an underground power cable, including the soil thermal resistivity, thermal diffusivity and thermal stability. Each of these properties is a function of soil moisture which is, in turn, a function of past weather, soil composition, and biological burden. The Neher-McGrath formalism has been widely used for thermal cable design. However, this formalism assumes knowledge of soil thermal properties (resistivity and diffusivity). For design purposes, these parameters should be treated statistically, since weather varies greatly from year-to-year. As well, soil thermal property surveys are normally required along the route to assess the thermal qualitymore »