The use of artificial foundation soil cooling is used in various environments and provides benefits such as significantly decreasing construction periods and decreasing metal use in foundations due to a decreased length and number of piles required for proper support.
Temperature stabilizers are used for artificial freezing of thawed soils and for cooling of permafrost soils. In particular, temperature stabilizers are used to stabilize foundation soils to increase the load-bearing capacity of soil and pile foundations during construction, operation, and repair of pipelines and other structures of oil and gas transportation systems, maintenance of oil and gas fields, and other industrial and commercial structures installed in a permafrost zone.
Temperature stabilizers include leak-tight pipe constructions filled with a cooling agent. Temperature stabilizers include an aboveground portion (a condenser) and an underground portion (a vaporizer).
An effective method to maintain or to increase the frozen condition of the soil (i.e., decrease the temperature of the soil or reduce an increase in the temperature of the soil) in foundations of structures utilizes relatively low outdoor air temperatures along with vapor-liquid thermal siphons that are called temperature stabilizers. The operation of temperature stabilizers may vary by season, depending on an ambient air temperature.
A thermal siphon including a condensing section, a vaporizing section with a negative tilt, and a power fluid in the vaporizing section is disclosed by U.S. Pat. No. 4,961,463 (published on Sep. 10, 1990, IPC E02D13/115). This thermal siphon is inserted into soil without a well.
Compared with such designs of temperature stabilizers, the use of a well with a thermal siphon will allow replacement of temperature stabilizers without the use of any drilling equipment.
A temperature stabilizer that is placed in a well includes a cylindrical body with a top lid and a lower bottom. This stabilizer is disclosed by S. N. Okunev et al., Practice of temperature soil stabilizing systems for oil pipelines “ESPO” and “Vankor mine of OPS PURPE”, materials of the international conference “Permafrost Resources of Polar and Mountain Regions. Condition and Prospects of the Engineering Permafrost Study, pp. 139-141, Tyumen, 2008).
The disadvantage of this solution is the need to use disposable materials (such as construction foam) during installation of the temperature stabilizer into the well. The disposable materials can only be used in certain temperatures. Another disadvantage is the need to remove sealing materials and to clean the internal surface of the well prior to replacement of the temperature stabilizer during operation.
The closest solution is a temperature stabilizing device that contains a well. A cavity of the well is filled with a non-freezing liquid, and cooling elements are installed into the well. The top of the well and the cooling pipe are equipped with a lid having a hole to receive the cooling element, and a filling port with a plug (disclosed by RF patent No. 11671, published on Oct. 6, 2012, E02D3/115).