Composite inflatable thermal insulation system for mass concrete warehouse surface

Abstract

The invention discloses a composite inflation thermal insulation system for a mass concrete warehouse surface, which comprises a control system, a thermal insulation structure covering the concrete warehouse surface and an air source unit, the thermal insulation structure is formed by connecting a plurality of thermal insulation units, and each thermal insulation unit comprises an upper protection layer, a lower protection layer and an inflation thermal insulation layer, the inflation heat preservation layer is of a honeycomb structure made of a polymeric membrane and is provided with a plurality of air chambers which are communicated with one another, and each air chamber is of a regular hexagon structure. The control system comprises a control terminal, a first temperature sensor, a second temperature sensor and a pressure sensor matched with each heat preservation unit. The thickness of the inflation heat preservation layer is adjusted by monitoring the temperature, flexible adjustment of the inflation thickness is achieved, the heat preservation requirement of the concrete surface in the cold season is met, the temperature difference between the interior of concrete and the concrete surface is reduced as much as possible, the influence of humidity in the external environment is small, and the heat preservation effect is remarkable; in addition, the heat-preservation concrete can be repeatedly used, so that the heat-preservation cost of the mass concrete is reduced.

Description

Technical Field

[0001] This invention relates to the field of winter insulation for large-volume concrete, and in particular to a composite air-filled insulation system for the surface of large-volume concrete slabs. Background Technology

[0002] In the construction of large-volume concrete structures (such as hydraulic dams, lock foundations, and nuclear power plant foundations), the heat released during concrete hydration and the ambient temperature jointly determine the evolution of the internal temperature field. During winter construction, the low ambient temperature rapidly carries away the heat of hydration from the concrete surface, leading to a significant temperature difference between the internal and surface layers, creating a temperature gradient and triggering temperature cracks. These cracks not only affect the overall structural integrity but also reduce durability, and can even cause a chain reaction of problems such as leakage and steel corrosion. Therefore, temperature control of large-volume concrete structures has a decisive impact on their durability during cold seasons.

[0003] Existing winter insulation measures for large-volume concrete surfaces mainly include fixed insulation sheds, electric blanket covering, and heat storage curing. Fixed insulation sheds are enclosed spaces constructed using steel pipe supports, tarpaulins, and blankets, supplemented by electric heating equipment. However, these sheds have long construction periods, poor wind resistance, and excessively high insulation costs. Electric blanket covering involves directly covering the concrete surface with electric blankets containing built-in resistance wires or heating coils, which easily leads to uneven temperature distribution, high power consumption, and safety hazards such as electric leakage and fire. Heat storage curing utilizes the low thermal conductivity of insulation materials (such as dry cotton wool and foam insulation boards) to slow down heat loss from the concrete. However, in rainy or snowy weather, these materials are prone to moisture absorption and freezing, causing a sharp decline in insulation effectiveness and often failing to meet insulation requirements. To address these issues, a series of improved insulation measures have emerged, but these measures still suffer from technical shortcomings such as lack of intelligent control, poor environmental adaptability, and high insulation costs. Summary of the Invention

[0004] In view of this, the present invention proposes a composite air-filled insulation system for large-volume concrete slab surfaces.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: The composite air-filled insulation system for large-volume concrete slabs, as described in this invention, includes a control system, an insulation structure covering the concrete slab surface, and an air source unit for inflating and deflating the insulation structure. The insulation structure is composed of multiple insulation units connected together. Each insulation unit includes an upper protective layer, a lower protective layer, and an air-filled insulation layer disposed between the upper and lower protective layers. The upper protective layer is an upper protective blanket made of wear-resistant waterproof fabric and flexible foam rubber. The lower protective layer is a lower protective blanket made of wear-resistant waterproof fabric and insulation material, wherein the insulation material in the lower protective layer is cotton wool or felt. The air-filled insulation layer has a honeycomb structure made of polymer film, which has multiple interconnected air chambers, and the air chambers are regular hexagonal structures. The control system includes a control terminal, a first temperature sensor, a second temperature sensor, and a pressure sensor associated with each insulation unit. The first temperature sensor is located at the bottom of the lower protective layer and is used to monitor the temperature of the concrete surface. The second temperature sensor is located on the upper surface of the upper protective layer and is used to monitor the ambient temperature. The pressure sensor is located inside the inflatable insulation layer. The first temperature sensor, the second temperature sensor, and the pressure sensor are all wirelessly connected to the control terminal.

[0006] The beneficial effects are as follows: This invention can monitor the temperature of the concrete surface and the ambient temperature in real time. By adjusting the thickness of the inflatable insulation layer through temperature monitoring, the thickness of the inflatable layer can be flexibly adjusted to meet the insulation needs of the concrete surface in cold seasons, minimize the temperature difference between the inside and surface of the concrete, and improve the quality of the concrete. In addition, this invention uses inflatable insulation, which has good insulation effect and is less affected by the humidity of the external environment. When the thickness of the inflatable insulation layer is 10cm, its insulation effect is equivalent to a 24cm thick cotton quilt in a dry state and a 60cm thick cotton quilt in a damp state, with significant insulation effect and reduced insulation cost. Furthermore, this invention can be reused multiple times, further reducing the insulation cost of large-volume concrete projects (such as hydraulic dams, lock foundations, and nuclear power plant foundations).

[0007] Preferably, the gas source unit includes a gas filling and emptying device and a gas filling and emptying pipeline, and each of the heat preservation units has a gas valve, and the heat preservation unit is connected to the gas filling and emptying pipeline through the gas valve.

[0008] The beneficial effects are: This invention utilizes an inflation / deflation device to inflate multiple insulation units, achieving rapid inflation of the insulation units; after the insulation is completed, the inflation / deflation device can also be used to quickly deflate the insulation, enabling rapid disassembly of the insulation structure of this invention. The control input terminal of the inflation / deflation device is communicatively connected to the control output terminal of a control terminal, allowing for automatic control of the inflation / deflation device via the control terminal.

[0009] Preferably, the air source unit further includes an auxiliary heating device installed on the inflation / deflation pipeline. During actual installation, the auxiliary heating device heats the air, thereby increasing the temperature of the inflatable insulation layer and ensuring insulation during cold waves in winter. The auxiliary heating device is preferably an electric heating device, but a heat exchanger can also be used.

[0010] Preferably, the thickness of the upper protective layer is 0.5 cm, the thickness of the lower protective layer is 1.0 cm, and the minimum inflation height of the inflatable insulation layer during cold waves or wintering is specified. h 2 for ;in, μ Poisson's ratio for concrete α c The thermal conductivity of concrete is m. 2 / d; Q The duration of a cold wave and temperature drop is expressed in days (d). λ c is the thermal conductivity of concrete, kJ / (m·h·℃).

[0011] More preferably, the control system of the present invention further includes a mobile terminal, which is communicatively connected to the control terminal, making it convenient for staff to view at any time and also convenient for remote operation.

[0012] Compared with the prior art, the advantages of the present invention are as follows: This invention can monitor the temperature of the concrete surface and the ambient temperature in real time. By adjusting the thickness of the inflatable insulation layer according to the temperature, the thickness can be flexibly adjusted to meet the insulation needs of the concrete surface in cold seasons, minimizing the temperature difference between the inside and surface of the concrete and improving concrete quality. In addition, this invention uses inflatable insulation, which has good insulation effect and is less affected by the humidity of the external environment. When the insulation material is in a damp state, the insulation effect of the 10cm thick inflatable insulation layer of this invention is equivalent to that of a 24cm thick cotton quilt in a dry state and a 60cm thick cotton quilt in a damp state, with significant insulation effect and reduced insulation cost. Furthermore, this invention can be reused multiple times, further reducing the insulation cost of large-volume concrete projects (such as hydraulic dams, lock foundations, and nuclear power plant foundations). Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the insulation structure and air source unit in this invention.

[0014] Figure 2 This is a schematic diagram of the heat preservation unit described in this invention.

[0015] Figure 3 This is a cross-sectional view of the insulation unit of the present invention (the inflatable insulation layer is in a partially folded state).

[0016] Figure 4 This is a schematic diagram of the inflatable insulation layer in the insulation unit of the present invention.

[0017] Figure 5 This is a circuit block diagram of the present invention.

[0018] Figure 6 This is a schematic diagram of the air valve of the present invention. Detailed Implementation

[0019] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. These embodiments are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operation processes.

[0020] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0021] Taking hydraulic dams as an example, hydraulic dams are large-volume concrete structures and are often quite tall. In actual construction, they are typically poured in sections (with a pouring height of approximately 3 meters). Each poured section of concrete requires curing, and in winter, the concrete surface needs to be insulated to prevent excessive temperature differences. The following section uses the insulation of one section of concrete as an example to illustrate the invention in more detail: Combination Figure 1-5 As can be seen, this invention proposes a composite air-insulated thermal insulation system suitable for large-volume concrete slab surfaces, including a control system, an insulation structure covering the concrete slab surface, and an air source unit for inflating and deflating the insulation structure. The insulation structure is composed of multiple insulation units 100 connected together. Each insulation unit 100 has three layers of insulation, including an upper protective layer 101, a lower protective layer 102, and an air-insulated layer 103 disposed between the upper and lower protective layers 101 and 102. The upper protective layer 101 is an upper protective blanket made of wear-resistant waterproof cloth and flexible foam rubber, and the lower protective layer 102 is a lower protective blanket made of wear-resistant waterproof cloth and insulation material. The insulation material in the lower protective layer 102 is cotton wool or felt. The air-insulated layer 103 has a honeycomb structure made of polymer film, which has multiple interconnected air chambers with a regular hexagonal structure (see details). Figure 4 ); The control system includes a control terminal, a first temperature sensor, a second temperature sensor, and a pressure sensor that is paired with each thermal insulation unit 100. The first temperature sensor is arranged at the bottom of the lower protective layer 102, and the probe of this sensor protrudes downward from the lower protective layer 102 for monitoring the temperature of the concrete surface. The second temperature sensor is arranged at the top of the upper protective layer 101, and the probe of this sensor is located in the external environment for monitoring the external environmental temperature. The pressure sensor is arranged in the inflatable thermal insulation layer 103. The first temperature sensor, the second temperature sensor, and the pressure sensor are all wirelessly connected to the control terminal, and can transmit the monitored temperature signals and pressure signals to the control terminal in real time, thereby achieving real-time monitoring of the temperature and the pressure in the inflatable thermal insulation layer 103.

[0022] After the pouring is completed, the composite inflatable thermal insulation system of the present invention can be covered on the concrete surface. The two temperature sensors are used to monitor the temperature of the concrete surface and the external environmental temperature in real time, and the pressure sensor is used to monitor the pressure of each thermal insulation unit 100 in real time. The thickness of the inflatable thermal insulation layer 103 of the thermal insulation unit 100 can be flexibly adjusted according to the temperature change situation to meet the thermal insulation requirements of the concrete surface in cold seasons, minimize the temperature difference between the inside and the surface of the concrete as much as possible, improve the quality of the concrete, and further improve the construction quality of the entire project. In addition, the present invention uses inflatable thermal insulation, which has good thermal insulation effect and is less affected by the humidity in the external environment. Moreover, the present invention can be reused multiple times, reducing the thermal insulation cost of mass concrete projects.

[0023] The thermal insulation unit 100 of the present invention is integrally in a rectangular structure or a square structure. For convenient connection, each long-edge edge of the thermal insulation unit 100 has a lapping edge with a width of not less than 20 cm, and the lapping edges between the thermal insulation units 100 are lapped together. To ensure the integrity and stability of the thermal insulation structure, magnets can be installed on the lapping edges of the thermal insulation unit 100, and the adsorption of the magnets is used to further ensure the reliable connection between the thermal insulation units 100.

[0024] During actual installation, if the surface area of the concrete is large, the gas source unit can be two or more, and each gas source unit corresponds to a certain number of thermal insulation units 100 to meet the rapid inflation requirement. Figure 1As can be seen, the air source unit includes an inflation / deflation device and inflation / deflation pipelines. The inflation / deflation pipelines include a main pipeline 203 and multiple branch pipelines 204 connected to the main pipeline 203. The main pipeline 203 uses rigid PVC pipe to ensure the stability of the air path; the branch pipelines 204 use flexible hoses for flexible installation. Each insulation unit 100 has an air valve 205 (with a quick-connect plug) that communicates with the air chamber of the inflatable insulation layer 103. Each branch pipeline connects to the air valve 205 of one insulation unit 100, thus achieving quick connection between the air source unit and the insulation unit 100 and facilitating disassembly. Alternatively, the insulation unit 100 can have two air valves 205, enabling rapid inflation and deflation of each insulation unit 100.

[0025] Of course, in actual installation, multiple adjacent insulation units 100 can also be modularized, that is, the air valves 205 of the air-filled insulation layer 103 of adjacent insulation units 100 are connected through connecting pipes, so that multiple insulation units 100 can be interconnected, and multiple insulation units 100 can be simultaneously inflated and deflated, thereby improving work efficiency.

[0026] In actual installation, to improve the level of automation, the control input terminal of the inflation / deflation device 201 is communicatively connected to the control output terminal of the control terminal, allowing the control terminal to control the start and stop of the inflation / deflation device 201. For short-term heat preservation scenarios, an electric air pump can also be used to replace the larger inflation / deflation device.

[0027] In actual installation, the air valve 205 has a manual knob 205a and a quick-connect plug 205b. For concrete insulation with a relatively small area, a portable air inflator can be used. Connect the quick-connect plug 205b to the air valve 205 on the insulation unit 100, and tighten the manual knob 205a after inflation. See details below. Figure 6 ; If the area of ​​the dam concrete slab is large and the number of insulation units is large, the air valve 205 on the insulation unit 100 is preferably a solenoid valve, which facilitates the connection with the branch pipeline. The on and off of the air valve 205 can be controlled by the control terminal, thereby improving the air filling and releasing efficiency of the insulation unit.

[0028] The gas source unit of the present invention also includes an auxiliary heating device 202 disposed on the inflation / deflation pipeline. During actual installation, the auxiliary heating device 202 can heat the air, thereby increasing the temperature of the inflatable insulation layer 103 and ensuring insulation during cold winter periods. Preferably, the auxiliary heating device 202 is an electric heating device.

[0029] The control system of the present invention also includes a mobile terminal, which is communicatively connected to the control terminal. Staff can use the mobile terminal to view the status of the insulation unit 100 and the temperature of the concrete surface in real time. In cold weather, the mobile terminal can be used to remotely operate the insulation unit 100 to fill it with hot air to ensure the insulation effect.

[0030] During the cold season, the air thickness of the air-filled insulation layer 103 can be determined based on the heat release of the concrete to meet actual insulation requirements and avoid cracks caused by large temperature differences, especially during cold waves. The specific calculation process is as follows: The "Design Code for Concrete Gravity Dams" (SL319-2018) specifies that several insulation layers are attached to the concrete surface. The total thermal resistance of the three-layer insulation of this invention can be calculated based on the thermal resistance of each insulation layer. Specifically, the thermal resistance of each insulation layer... R i Total thermal resistance of the three insulation layers R 总 The calculations are shown in formulas (1) and (2) respectively: (1) (2) In the formula, h i For the thickness of the insulation layer, λ i The thermal conductivity of the insulation material used in the insulation layer. k 1 Wind speed correction factor (for airtight insulation layers) k 1 =1.3), k 2 This is a moisture level correction factor (3-5 if the insulation material is damp; 1 if the insulation material is dry); 1 / β 0 The thermal resistance between the outermost insulation layer (in this invention, the outermost insulation layer is the upper protective layer) and the air. (in the formula) υ a For wind speed, this invention uses [the wind speed] in the calculation. υ a =6.0m / s calculation β ).

[0031] The equivalent heat transfer coefficient of concrete surface releasing heat to the surrounding medium through the insulation layer β The calculation formula is as follows: (3) In this invention, the upper protective layer 101 is a protective blanket made of wear-resistant waterproof fabric and flexible foam rubber, with a thickness of 0.5 cm and a thermal conductivity of 0.15 kJ / (m·h·℃). The inflatable insulation layer 103 uses gas insulation, with a maximum inflation thickness of 15 cm and a thermal conductivity of 0.08 kJ / (m·h·℃) when at rest. The lower protective layer 102 is a protective blanket made of wear-resistant waterproof fabric and insulation material. The insulation material in the lower protective layer 102 is cotton wool or felt, with a filling thickness of 1 cm and a thermal conductivity of 0.17 kJ / (m·h·℃). In a dry state... k 1 =1.3, k 2 =l, the comprehensive heat release coefficient of the three-layer insulation structure in this invention is calculated by the above formulas (1)-(3). β The heat retention capacity is 0.70–12.5 kJ / (m·h·℃) (the thickness of the inflatable insulation layer 103 is calculated as 0–15 cm). With an inflatable thickness of 10 cm, the insulation effect of this invention is equivalent to that of a 24 cm thick cotton quilt; in a damp state, k 1 =1.3, k 2 =3, when the inflation thickness is 10cm, its insulation effect is equivalent to a 24cm thick cotton quilt in a dry state and a 60cm thick cotton quilt in a damp state. Therefore, it can be seen that the insulation structure covering the concrete silo surface in this invention has a significantly better insulation effect than an ordinary cotton quilt.

[0032] In practical use, the calculation process for the minimum inflation thickness of the inflatable insulation layer 103 in this invention is as follows: To ensure that the surface temperature stress of concrete does not exceed the allowable stress during a cold wave, the equivalent heat transfer coefficient required for the concrete surface to release heat to the surrounding medium through the insulation layer is... β Calculate using the following formula: (4) (5) (6) (7) In the formula, m Poisson's ratio for concrete λ c α is the thermal conductivity of concrete. c The thermal conductivity of concrete, Q Indicates the duration of the cold wave and temperature drop; r 1 To account for the influence coefficient of concrete creep, E For concrete elastic modulus, tm This refers to the average age of concrete during the cold wave and temperature drop period. a This is the coefficient of expansion of concrete. A This refers to the temperature drop; s a This refers to the allowable stress of concrete. s 0 Stress caused by other factors; P These are parameters related to the duration of cold waves.

[0033] Among them, during the wintering period, the b-value of concrete surface insulation and r Calculate using the following formulas respectively: (8) (9) Based on the above formulas (3) and (4), the cold wave and overwintering time (let) can be calculated. h 上 =0.5cm h 下 =1cm), then the minimum thickness of the air-filled insulation layer 103 in the middle layer is... h 2 for During winter, the inflation thickness can be flexibly adjusted according to actual needs to meet the insulation requirements of the concrete slab surface.

[0034] In practical use, the insulation unit 100 of the present invention can be laid sequentially on the concrete slab surface after pouring, and the air valve 205 can be connected to the branch pipe. The inflation and deflation device 201 can be started to inflate the air insulation layer 103 of the insulation unit 100 until the preset pressure is reached. Then, multiple air valves 205 and inflation and deflation device 201 can be closed to achieve pressure maintenance of each insulation unit 100. When a cold wave occurs, hot air can be added to the inflatable insulation layer 103 of the insulation unit 100 to improve the insulation effect and reduce the temperature difference between the concrete surface and the surrounding environment. After the insulation is completed, the air source unit will be disassembled and the insulation units 100 will be removed one by one for future use, improving the recycling rate and reducing the insulation cost.

[0035] In summary, this invention monitors the temperature of the concrete surface and the ambient temperature, and adjusts the thickness of the inflatable insulation layer accordingly, enabling flexible adjustment of the inflatable thickness to meet the insulation needs of the concrete surface during cold seasons. This minimizes the temperature difference between the inside and surface of the concrete, improving concrete quality. Furthermore, this invention uses inflatable insulation, which provides excellent insulation performance and is less affected by humidity in the external environment. When the insulation material is damp, a 10cm thick inflatable insulation layer provides the same insulation effect as a 60cm thick quilt, significantly reducing insulation costs. Moreover, this invention can be reused multiple times, further reducing insulation costs for large-volume concrete projects (such as hydraulic dams, lock foundations, and nuclear power plant foundations).

Claims

1. A composite air-filled insulation system suitable for large-volume concrete slab surfaces, characterized in that: The system includes a control system, an insulation structure covering the concrete slab surface, and an air source unit for inflating and deflating the insulation structure. The insulation structure is composed of multiple insulation units connected together. Each insulation unit includes an upper protective layer, a lower protective layer, and an inflatable insulation layer disposed between the upper and lower protective layers. The upper protective layer is an upper protective blanket made of wear-resistant waterproof fabric and flexible foam rubber. The lower protective layer is a lower protective blanket made of wear-resistant waterproof fabric and insulation material, and the insulation material in the lower protective layer is cotton wool or felt. The inflatable insulation layer is a honeycomb structure made of polymer film, which has multiple interconnected air chambers, and the air chambers are regular hexagonal structures. The control system includes a control terminal, a first temperature sensor, a second temperature sensor, and a pressure sensor associated with each insulation unit. The first temperature sensor is located at the bottom of the lower protective layer and is used to monitor the temperature of the concrete surface. The second temperature sensor is located on the upper surface of the upper protective layer and is used to monitor the temperature of the concrete surface. The pressure sensor is located inside the inflatable insulation layer. The first temperature sensor, the second temperature sensor, and the pressure sensor are all wirelessly connected to the control terminal.

2. The composite air-filled insulation system for large-volume concrete slabs according to claim 1, characterized in that: The gas source unit includes a charging and discharging device and a charging and discharging pipeline. Each of the insulation units has a gas valve, and the insulation unit is connected to the charging and discharging pipeline through a quick-connect gas valve.

3. The composite air-filled insulation system for large-volume concrete slabs according to claim 2, characterized in that: The gas source unit also includes an auxiliary heating device installed on the gas filling and discharging pipeline.

4. The composite air-filled insulation system for large-volume concrete slabs according to claim 1, characterized in that: The upper protective layer has a thickness of 0.5 cm, the lower protective layer has a thickness of 1.0 cm, and the minimum inflation height of the inflatable insulation layer during cold waves or wintering is specified. h 2 for ;in, μ Poisson's ratio for concrete α c The thermal conductivity of concrete is m. 2 / d; Q The duration of a cold wave and temperature drop is expressed in days (d). λ c is the thermal conductivity of concrete, kJ / (m·h·℃).

5. The composite air-filled insulation system for large-volume concrete slabs according to claim 1, characterized in that: It also includes a mobile terminal, which is communicatively connected to the control terminal.

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