An intelligent temperature control method for winter maintenance of large underground spaces in severe cold regions

Abstract

The present invention belongs to the technical field of temperature control for large underground spaces, and provides an intelligent temperature control method for wintering maintenance of large underground spaces in severely cold regions, solving the problem of cracking and deformation of concrete foundations caused by the expansion of the frozen soil volume during the freezing process during the wintering of projects under construction and delayed construction. The total heat consumption per unit time of the basement is calculated; the number of heaters required to maintain the preset wintering temperature of the basement is determined based on the total heat consumption per unit time of the basement and the power of a single heater; the heaters and air supply belts are placed in preset positions to form a temperature control system for the large underground space during the wintering; the temperature sensor transmits the detected basement temperature signal to the main control module, and the main control module controls the start and stop of the heater to maintain the basement at the preset wintering temperature. The present invention forms an intelligent temperature control system for the large underground space during the wintering by rationally calculating and planning the number and position of the heaters in the basement, and through the cooperation of the temperature sensor and the main control module.

Description

Technical Field

[0001] The present invention belongs to the technical field of temperature control of ultra-large underground spaces, and in particular relates to an intelligent temperature control method for wintering maintenance of ultra-large underground spaces in severely cold areas. Background Art

[0002] Construction projects in northern my country often require wintering for ongoing and delayed projects that span multiple years. During the winter, the frozen soil expands, generating expansive forces that can cause the foundation and superstructure to lift and deform. This can lead to cracks in the concrete foundation, damage to the waterproofing membrane below, and even endanger the safety of the foundation structure. Reinforcement measures, or even demolition and reconstruction, are necessary when work resumes in the spring. This not only causes financial losses for the construction company but also extends the construction period. To minimize and avoid this type of loss and waste, winter maintenance of buildings is crucial. Summary of the Invention

[0003] Aiming at the problem that during the wintering of projects under construction and delayed construction, the volume of the permafrost expands during the freezing process, causing cracks and deformation of the concrete foundation, damaging the waterproof membrane below the foundation, and even endangering the safety of the foundation structure, the purpose of the present invention is to provide an intelligent temperature control method for wintering maintenance of large underground spaces in severe cold areas. By intelligently setting up a large underground space wintering temperature control system, the method can achieve

[0004] To achieve the above objectives, the present invention adopts the following technical solution: an intelligent temperature control method for wintering maintenance of ultra-large underground spaces in severe cold regions, comprising the following steps:

[0005] S1: Calculate the total heat consumption per unit time of the basement based on the total volume and total heat dissipation area of ​​the basement, the thickness and material of the basement structure maintenance layer, and the temperature difference between the inside and outside of the basement;

[0006] S2: Determine the number of heaters required to maintain the preset wintering temperature of the basement based on the total heat consumption per unit time and the power of each heater;

[0007] S3: Determine the installation location of the basement heater and plan the route of the air supply belt connected to the heater. Place the heater and air supply belt in the preset location to form a large-scale basement temperature control system for wintering.

[0008] S4: A temperature sensor is installed in the basement. The temperature sensor transmits the detected basement temperature signal to the main control module. The main control module controls the start and stop of the heater to maintain the basement at a preset wintering temperature.

[0009] Preferably, in step S1, the calculation formula for the total heat consumption per unit time in the basement is:

[0010] Q0=Q1+Q2

[0011]

[0012]

[0013] Among them: Q0 is the total heat consumption of the basement per unit time; Q1 is the heat dissipation of the basement per unit time; Q2 is the heat loss during ventilation in the basement per unit time; is the total heat dissipation area of ​​the basement; K is the total heat transfer coefficient of the basement structure maintenance layer; T b The preset wintering temperature in the basement; T a is the temperature outside the basement; V is the total volume of the basement; N is the number of air changes per unit time; C a is the specific heat capacity of air; P a is the bulk density of air.

[0014] Preferably, the total heat dissipation area A of the basement includes the area A1 of the basement top, the side area A2 of the basement holes, and the area A3 of the concrete layer of the basement side walls.

[0015] Preferably, the basement structure maintenance layer includes multiple structural layers arranged in sequence, and the calculation formula of the total heat transfer coefficient K of the basement structure maintenance layer is:

[0016]

[0017] Where: d1 is the thickness of the first structural layer; λ1 is the heat transfer coefficient of the first structural layer; d n is the thickness of the nth structural layer; λ n is the heat transfer coefficient of the nth structural layer.

[0018] Preferably, the basement structure maintenance layer includes a reinforced concrete layer, an extruded board layer and a perlite layer arranged in sequence from the inside to the outside.

[0019] Preferably, in step S3, air heaters are required to be arranged at the stairwells, elevator entrances and reserved openings in the basement, and the remaining air heaters are evenly arranged in the basement, and all the air heaters are numbered in the main control module.

[0020] Preferably, in step S4, temperature sensors are arranged at the corners of the basement, the remaining temperature sensors are evenly arranged in the basement, and all temperature sensors are numbered in the main control module.

[0021] Preferably, in step S5, a threshold value of the basement temperature is set in the main control module. When it is detected that the basement temperature reaches the lower limit of the threshold, the main control module controls the heater to start until the temperature reaches the upper limit of the threshold, and the main control module controls the heater to stop.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention reasonably calculates and plans the number and position of heaters in the basement, and forms an intelligent temperature control system for wintering in a large basement space through the cooperation of temperature sensors and main control modules. It solves the problem of cracking and deformation of concrete foundations caused by the expansion of the frozen soil volume during the freezing process during the wintering of projects under construction and delayed construction, which damages the waterproof membrane below the foundation and even endangers the safety of the foundation structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 is a flow chart of the present invention;

[0026] Figure 2 It is a schematic diagram of the arrangement of the heater of the present invention;

[0027] Figure 3 Schematic diagram of the arrangement of the temperature sensor of the present invention;

[0028] Figure 4 It is a structural schematic diagram of the heater of the present invention.

[0029] In the figure: 1-heater; 2-air supply belt; 3-connecting pipe; 4-air outlet; 5-temperature sensor; 6-basement. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention are clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other implementations derived by ordinary technicians in this field based on the embodiments of the present invention without creative work are within the scope of protection of the present invention.

[0031] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which the present invention can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in the present invention without affecting the efficacy and purpose that can be achieved by the present invention. It should be noted that in this specification, relational terms such as first and second are only used to distinguish one entity from other entities, and do not necessarily require or imply any actual relationship or order between these entities.

[0032] The present invention provides an embodiment:

[0033] like Figures 1 to 4 As shown, an intelligent temperature control method for winter maintenance of a large underground space in a severely cold region includes the following steps:

[0034] S1: Calculate the total heat consumption per unit time of the basement based on the total volume and total heat dissipation area of ​​the basement, the thickness and material of the basement structure maintenance layer, and the temperature difference between the inside and outside of the basement;

[0035] S2: Determine the number of heaters required to maintain the preset wintering temperature of the basement based on the total heat consumption per unit time and the power of each heater;

[0036] S3: Determine the installation location of the basement heater and plan the route of the air supply belt connected to the heater. Place the heater and air supply belt in the preset location to form a large-scale basement temperature control system for wintering.

[0037] S4: A temperature sensor is installed in the basement. The temperature sensor transmits the detected basement temperature signal to the main control module. The main control module controls the start and stop of the heater to maintain the basement at a preset wintering temperature.

[0038] The calculation formula for the total heat consumption per unit time in the basement is:

[0039] Q0=Q1+Q2

[0040]

[0041]

[0042] Among them: Q0 is the total heat consumption of the basement per unit time; Q1 is the heat dissipation of the basement per unit time; Q2 is the heat loss during ventilation in the basement per unit time; is the total heat dissipation area of ​​the basement; K is the total heat transfer coefficient of the basement structure maintenance layer; T b The preset wintering temperature in the basement; Ta is the temperature outside the basement; V is the total volume of the basement; N is the number of air changes per unit time; C a is the specific heat capacity of air; P a is the bulk density of air.

[0043] The basement structure maintenance layer includes multiple structural layers arranged in sequence. The calculation formula for the total heat transfer coefficient K of the basement structure maintenance layer is:

[0044]

[0045] Where: d1 is the thickness of the first structural layer; λ1 is the heat transfer coefficient of the first structural layer; d n is the thickness of the nth structural layer; λ n is the heat transfer coefficient of the nth structural layer.

[0046] In this example, assuming a unit time of 1 hour, the basement structure maintenance layer includes, from the inside out, a reinforced concrete layer, an extruded board layer, and a perlite layer. The reinforced concrete layer has a thickness d1 of 0.35 m and a heat transfer coefficient λ1 of 1.74; the extruded board layer has a thickness d2 of 0.08 m and a heat transfer coefficient λ2 of 0.03; and the perlite layer has a thickness d3 of 0.5 m and a heat transfer coefficient λ3 of 0.07. Substituting these data into the calculation formula for the total heat transfer coefficient K of the basement structure maintenance layer, the total heat transfer coefficient K for the basement structure maintenance layer is 0.1.

[0047] In this embodiment, the total heat dissipation area A of the basement 6 includes the area A1 of the basement top, the side area A2 of the basement hole, and the area A3 of the concrete layer of the basement side wall. The area A1 of the basement top is measured and calculated to be 25190m 2 The side area A2 of the basement hole was measured and calculated to be 287.3m 2 The area A3 of the concrete layer of the basement side wall is measured and calculated to be 383.1m 2 ; Preset wintering temperature T in basement 6 b Take 5℃; the temperature outside the basement 6 is T a Take -20℃; substitute it into the calculation formula of the heat dissipation Q1 per unit time in the basement, and we can get Q1 as 80142KJ.

[0048] In this embodiment, the total volume V of the basement 6 is measured and calculated to be 95722m 3 Since the basement entrance is blocked in this embodiment, the ventilation frequency N within 1 hour is 0, and the specific heat capacity of air C a Take 1KJ / kg, the air density P a Take 1.37kg / m 3 , substituting it into the heat loss Q2 during ventilation in the basement per unit time, we can obtain that Q2 is 0.

[0049] In summary, the total heat consumption Q0 in the basement within 1 hour is 80142KJ.

[0050] In this embodiment, the power of the heater 1 is 20kW, and the heat generated by one heater 1 per hour is 72000KJ. The thermal efficiency of electric heating is close to 1, and the loss is not considered here; assuming that the time required for the basement 6 to heat up from -20°C to 5°C is set to 0.7h, the required heat is 95722×1×1×1.37×(20+5)÷3.6=910689KJ. The calculation of heat here is the same as Q2, because the heat discharged by one ventilation is equivalent to the heat required for the basement 6 to heat up from the temperature outside the basement to the preset wintering temperature inside the basement. The heat required to raise the temperature of basement 6 from -20°C to 5°C divided by the time required is the net heat required by heater 1 per hour, 910689 / 0.7=1359858 kJ. Adding this to the heat dissipation in the basement for 1 hour is the total heat provided by n heaters 1 per hour: 1359858+80142=1440000 kJ. Calculation shows that the number of heaters 1 required is 1440000 / 72000=20.

[0051] Heaters 1 need to be arranged at the stairwells, elevator entrances and reserved openings in the basement. The remaining heaters 1 are evenly arranged in the basement, and all the heaters 1 are numbered in the main control module. The heater 1 is connected to the air supply belt 2 through a connecting pipe 3. Several air outlets 4 are set on the air supply belt. The length of the air supply belt is set according to the air supply length of the heater 1; temperature sensors 5 need to be arranged at the corners of the basement. The remaining temperature sensors 5 are evenly arranged in the basement, and all the temperature sensors 5 are numbered in the main control module.

[0052] A threshold for the basement temperature is set in the main control module. When it is detected that the basement temperature reaches the lower limit of the threshold, the main control module controls the heater 1 to start, and until the temperature rises to the upper limit of the threshold, the main control module controls the heater 1 to stop.

[0053] The foregoing description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be readily conceived by a person skilled in the art within the technical scope disclosed herein should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. An intelligent temperature control method for winter maintenance of large underground spaces in severe cold regions, characterized in that: The following steps are involved: S1: The total heat consumption per unit time of the basement is calculated based on the total volume and total heat dissipation area of ​​the basement, the thickness and material of the basement structure maintenance layer, and the temperature difference between the inside and outside of the basement. In step S1, the total heat consumption per unit time of the basement is calculated as follows: Among them: Q0 is the total heat consumption of the basement per unit time; Q1 is the heat dissipation of the basement per unit time; Q2 is the heat loss during ventilation in the basement per unit time; is the total heat dissipation area of ​​the basement; K is the total heat transfer coefficient of the basement structure maintenance layer; T b The preset wintering temperature in the basement; T a is the temperature outside the basement; V is the total volume of the basement; N is the number of air changes per unit time; C a is the specific heat capacity of air; P a is the bulk density of air; S2: Determine the number of heaters required to maintain the preset wintering temperature of the basement based on the total heat consumption per unit time of the basement, the power of a single heater, and the time required for the basement to heat up; S3: Determine the installation location of the basement heater and plan the route of the air supply belt connected to the heater. Place the heater and air supply belt in the preset location to form a large-scale basement temperature control system for wintering. S4: A temperature sensor is installed in the basement. The temperature sensor transmits the detected basement temperature signal to the main control module. The main control module controls the start and stop of the heater to maintain the basement at a preset wintering temperature.

2. The intelligent temperature control method for winter maintenance of large underground spaces in severe cold regions according to claim 1 is characterized by: The total heat dissipation area A of the basement includes the area A1 of the basement top, the side area A2 of the basement holes and the area A3 of the concrete layer of the basement side walls.

3. The intelligent temperature control method for winter maintenance of large underground spaces in severe cold regions according to claim 1 is characterized by: The basement structure maintenance layer includes multiple structural layers arranged in sequence. The calculation formula of the total heat transfer coefficient K of the basement structure maintenance layer is: Where: d1 is the thickness of the first structural layer; λ1 is the heat transfer coefficient of the first structural layer; d n is the thickness of the nth structural layer; λ n is the heat transfer coefficient of the nth structural layer.

4. The intelligent temperature control method for winter maintenance of large underground spaces in severe cold regions according to claim 3 is characterized by: The basement structure maintenance layer comprises a reinforced concrete layer, an extruded board layer and a perlite layer which are arranged in sequence from the inside to the outside.

5. The intelligent temperature control method for winter maintenance of large underground spaces in severe cold regions according to claim 1 is characterized by: In step S3, air heaters are required to be arranged at the stairwells, elevator entrances and reserved openings in the basement, and the remaining air heaters are evenly arranged in the basement, and all the air heaters are numbered in the main control module.

6. The intelligent temperature control method for winter maintenance of large underground spaces in severe cold regions according to claim 5 is characterized by: In step S4, temperature sensors are arranged at the corners of the basement, and the remaining temperature sensors are evenly arranged in the basement, and all temperature sensors are numbered in the main control module.

7. The intelligent temperature control method for winter maintenance of large underground spaces in severe cold regions according to claim 1 is characterized by: In step S5, a threshold value of the basement temperature is set in the main control module. When it is detected that the basement temperature reaches the lower limit of the threshold, the main control module controls the heater to start, and until the temperature rises to the upper limit of the threshold, the main control module controls the heater to stop.

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