In this chapter, the obtained experimental results are presented and analyzed from the thermal experiments that have been achieved on the different samples of natural soils. These soils can be used as backfill soil in buried cables. The obtained results are used to study the drying out phenomena and its effects on the cable insulation. These experiments study the temperature against heat flux density at infinity Pf value and the specification of the soil. An instrument simulates a real power buried cable is used. This apparatus was described in chapter five in detail.
Top6.1 The Recorded Temperature Against Time For The Tested Sand Types
The relationship between temperature against time for sand1 at (Qh=255, PF= ∞) is shown in (Figure 1a) .It is noticed that the temperature increases slightly with the increase of heating time while the heat flux density and moisture content are not changed. Also we can see that the temperature reached steady state after 10 hrs and then the temperature became constant with the increase of time. Before the steady state the rise of temperature was sharp.
Figure 1a. Temperature against time for Sand1 in case of pf=∞ Qh=255 (w/m2)
The relationship between temperature against time for sand 2 at the stated conditions of (Qh and PF) is shown in (Figure 2a) .From this figure it is noticed that the temperature increases slightly with the increase of heating time, heat flux density and moisture content are constant during the test. Similar results are obtained for lime, clay,mixture 1(50% sand 1 + 50% lime), mixture 2 (25% sand 1+ 75% Lime), mixture 3 (75% sand 1 + 25% Lime) and mixture 4 (75% sand 1 + 25% Lime) in Figures 3a, 4a, 5a, 6a, 5a, 6a, 7a, 8a and 9a.
Figure 2a. Temperature against time for Sand2 in case of pf=∞ Qh=255 (w/m2)
Figure 3a. Temperature against time for Sand3 in case of pf=∞ Qh=255 (w/m2)
Figure 4a. Temperature against time for Sand4 in case of pf=∞ Qh=255 (w/m2)
Figure 5a. Temperature against time for Mix1 in case of pf=∞ θa =255 (w/m2)
Figure 6a. Temperature against time for Mix2 in case of pf=∞ Qh=255 (w/m2)
Figure 7a. Temperature against time for Mix3 in case of pf=∞ Qh =255 (w/m2)
Figure 8a. Temperature against time for Mix4 in case of pf=∞ Qh=255 (w/m2)
Figure 9a.
Temperature against time for Mix5 in case of pf=∞ Qh=255 (w/m2)