Thermophysical Properties of Bentonite–Sand/Fly Ash-Based Backfill Materials for Underground Power Cable

The surrounding (backfill) materials around the underground power cable systems are essential for dissipating heat away from it, during exertion phases. dissipation restrains thermal instability and risk of progressive drying backfill materials, thus reducing stress on cable. Thermal indicates reduction in properties (conductivity or diffusivity) due to migration moisture because accumulation. Thus, should have adequate water retention capacity transfer source area with minimal migration. bentonite has high capacity, but low conductivity, whereas sand/fly ash exhibits higher conductivity than bentonite. addition promotes holding thermophysical sand fly ash. Therefore, this study presents bentonite–fly (B–F) bentonite–sand (B–S), at varying weight-percent Various compositions mixtures were compacted dry densities, contents variation measured using a dual needle probe ‘KD2 Pro’ room temperature. deals systematic evaluation volumetric specific diffusivity against density content. threshold content (TWC) been determined diffusivity–water curve, it correlated plastic limit (PL) optimum (OMC). Thereafter, efficacies two prediction models also evaluated statistically respect experimental results.