Heat transfer in dry granular material is dominated by conduction among the grains. The quality and quantity of the contact dictate the preferred heat path. Owing to the high thermal conductivity and considerable mechanical strength, nanomaterials are suitable to improve the contact by filling inter- and intra-granular pores. A thermo-mechanical study with 0–5 weight percentage of 63 nm and 125 nm silicon carbide (SiC)/sand mixtures has been conducted. A numerical model based on a modified effective-medium approximation considering the effective mean free path is implemented in the lattice element method with gas theory to predict the ETC of the mixtures. The numerical modeling and experimental results showed satisfactory agreement to a large extent. To test the mechanical stability of the developed mix, direct shear test and consolidation tests have been performed on the nano-geomixture to observe changes in the mechanical strength due to a powder-like appearance of SiC. No significant reduction in strength and settlement behavior of the mixture has been reported. The developed nanocomposite could be used in energy geotechnics application.