diagram of the system for providing dryness in the plan is shown in Fig. 7. Cross-
section A-A is shown in Figure 8.
The system for ensuring dryness has a recessed part of the structure (1), protected
from the outside along the perimeter and from below by a continuous clay screen (2),
a water basin (3), the volume of which is filled with water-permeable soil-filler and
contains several threads of a heat-conducting electric cable (4), parameters which are
determined by heat engineering calculation.
Figure 6. Scheme of operation of the security system of the in-depth parts
of structures
In the upper part of the header (3), perforated in the upper part of the horizontal
drain (6), the parameters of which are determined by hydraulic calculation, and the
drainage water is collected in a standard drainage well (7), arranged along the perimeter
of the deepened part of the structure (1).
The dryness maintenance system works as follows.
On the thread of the thermal conductive electrical cable (4), gradually starting
from the uppermost one, a voltage is applied. The electric current passing through the
filaments of the cable (4) heats them, after which a layerwise (top-down) heating of the
soil-the filler of the header (3) and the conversion of the ball water accumulated in each
into a vapor-like state occurs, followed by the lifting of this substance along the water
header (3) upwards.
Reaching the blind area (5), the vapor-like substance turns into water, due to the
decrease in the temperature gradient and under the action of gravitational forces, it
starts moving down the water basin (3), where it is intercepted by a horizontal drain
(6) perforated in the upper part and diverted to the drainage pit (7) (see Figure 6, 7).
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