Dynamic control system for pipe roofing freezing method

Abstract

The invention relates to the technical field of freezing control, in particular to a pipe roof freezing method dynamic control system which comprises a temperature detection device, the temperature detection device comprises a plurality of hard balls connected through a connecting rope, and a puncturing mechanism and a self-power-generating mechanism are arranged in each hard ball. The self-power-generating mechanism generates current to supply power to the temperature sensing element based on the action of the puncturing mechanism on the liquid storage ball, the function of automatically activating the temperature sensing element when the soil reaches the preset freezing temperature is achieved, and therefore unnecessary energy consumption is reduced; the freezing wall thickness of different depths is calculated by monitoring the temperature values of different depths in the inspection hole and the monitoring hole in real time, precise regulation and control of the power of the refrigeration compressor are achieved, the freezing efficiency and safety are improved, and the risks of environmental influence and structural damage caused by improper temperature control are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of freezing control, in particular to a dynamic control system of a pipe curtain freezing method. Background Art

[0002] With the rapid development of China's economy and the acceleration of urbanization, various forms of tunnels are constantly being built. The construction of large-section, shallow-buried and dark-excavated tunnels is inevitable and a huge challenge facing modern construction technology. The advance pre-support system for shallow-buried and dark-excavated large-section tunnels has attracted much attention from all parties. It can effectively maintain the stability of the heading face, control stratum deformation, and prevent accidents such as collapse. It is directly related to tunnel safety and economic benefits. The pipe curtain advance pre-support system is widely used for its advantages of high space utilization, construction safety and little impact on the surrounding environment. The pipe curtain method is a method of constructing large sections with small equipment. It has a flexible cross-section and can form almost any tunnel cross-section shape. It has strong geological adaptability. The water stop between pipe curtains relies on tooth groove lock seals or freezing, horizontal MJS and other processes to form a continuous water stop curtain. Tooth lock buckles are generally used for pipe curtains with low water content, low water level, and short straight distance; horizontal MJS is an all-round high-pressure jetting technology. This method has the characteristics of strong adaptability, small disturbance to the surrounding soil, high degree of automation, etc. Horizontal MJS is generally used for pipe curtains with low water content, low water level, large burial depth and short straight distance. Freezing technology has strong adaptability to the shape of surrounding structures. As long as the layout of the freezing holes is accurate and the freezing time is sufficient, frozen walls of different shapes can be formed; it has good water-proof performance, and the frozen wall has good continuity after the circle is crossed and has a certain strength; in addition, it has little pollution to the formation. Since the freezing method only increases the strength of the in-situ soil by lowering the temperature, it does not change the formation composition, so it has little pollution to the formation. The freezing method can be applied to complex formations with large water volume, high water level and rich water.

[0003] At present, the freezing construction of pipe curtains uses a certain number of jacking pipes to form a force-bearing structure. By installing freezing pipes in the jacking pipes, the water-bearing strata around the pipe curtains are frozen, the water in the strata freezes, and the loose water-bearing rock and soil are turned into frozen soil, increasing its strength and stability, isolating groundwater, so that underground engineering excavation and masonry operations can be carried out under the protection of the frozen wall. This construction method fully combines the advantages of artificial freezing method and pipe curtain method, becoming a new tunnel construction method.

[0004] At the same time, this method also has certain risks. Insufficient cooling or external heat sources can cause the range and strength of the frozen soil curtain to degrade, and the frozen soil can melt quickly under the action of flowing water. Improper freezing will cause frost heave and thaw settlement, which will have a certain impact on the environment and can be destructive in severe cases. Improper control of thaw settlement can lead to structural differential settlement and long-term settlement. At the same time, existing technologies are unable to adjust the power of the refrigeration compressor based on the temperature field conditions. Summary of the invention

[0005] In view of the above-mentioned prior art, the present invention provides a dynamic control system for a pipe curtain freezing method, which mainly solves the technical problems existing in the above-mentioned background technology.

[0006] A first aspect of the present invention provides a dynamic control system for a pipe curtain freezing method, comprising a refrigeration system and a control center, wherein the control center is connected to the refrigeration system signal, and further comprising a temperature detection device, wherein the temperature detection device comprises a plurality of hard spheres, each of which is connected to each other by a connecting rope, wherein a liquid storage ball, a puncturing mechanism, a storage mechanism and a self-generating mechanism are provided inside the hard sphere, wherein the storage mechanism is used to store different liquid storage balls, wherein the puncturing mechanism is connected to a temperature conduction rod, wherein the temperature conduction rod extends to the outside of the hard sphere, wherein a temperature sensing element is detachably provided on the outer surface of the hard sphere, wherein the self-generating mechanism generates an electric current to power the temperature sensing element based on the action of the puncturing mechanism on the liquid storage ball, and the temperature sensing element is connected to the control center signal.

[0007] Optionally, a connecting tube and a closing cover threadedly connected to the connecting tube are provided at the top of the hard sphere, and rope buckles are provided at the closing cover and the bottom of the hard sphere. A partition plate is provided inside the connecting tube, and the partition plate divides the internal space of the connecting tube into a first area and a second area. The bottom of the partition plate is connected to the storage mechanism.

[0008] Optionally, the storage mechanism includes a collecting net, the collecting net includes a left collecting net and a right collecting net, one end of the left collecting net is connected to the partition plate, the other end is connected to the inner wall of one side of the hard sphere, and the center of the left collecting net is set below the first area, one end of the right collecting net is connected to the partition plate, the other end is connected to the inner wall of the other side of the hard sphere, and the center of the right collecting net is set below the second area.

[0009] Optionally, the puncturing mechanism includes a cold-shrinking hemisphere, a deformable arc wire and a puncturing needle. There are multiple cold-shrinking hemispheres, which are respectively arranged on both sides of the inner wall of the hard sphere. Each cold-shrinking hemisphere is connected to the temperature conduction rod. An elastic wire is fixedly connected between the multiple cold-shrinking hemispheres. The puncturing needle is arranged on the upper half of the elastic wire, one of the puncturing needles is aimed at the left collecting net, and the other puncturing needle is aimed at the right collecting net.

[0010] Optionally, the liquid storage ball includes an aqueous solution electrolyte ball, and the aqueous solution electrolyte ball enters the left collecting net or the right collecting net from different internal spaces of the connecting cylinder.

[0011] Optionally, the self-generating mechanism includes a cathode and an anode, the cathode and the anode are both arranged directly below the storage mechanism, and the anode and the cathode are connected via a transmission line.

[0012] Optionally, recessed areas are provided on both sides of the outer surface of the hard sphere, and conductive sheets are provided inside the recessed areas. The conductive sheets are connected to the transmission line, and the recessed areas are used to accommodate the temperature sensing element, and the conductive sheets are used to supply power to the temperature sensing element.

[0013] Optionally, the temperature sensing element includes a temperature sensor and a wireless communication unit, and the temperature sensor and the wireless communication unit are integrated in a box body. The size of the box body is consistent with the size of the recessed area, the temperature sensor is connected to the wireless communication unit signal, and the wireless communication unit is connected to the control center signal.

[0014] Optionally, different numbers of hard spheres are selected based on the depths of the inspection hole and the monitoring hole, connected to each other, and placed in the inspection hole and the monitoring hole.

[0015] A second aspect of the present invention provides a non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program includes a dynamic control system for the pipe curtain freezing method as described in any one of the above

[0016] The beneficial effects of the present invention are as follows: a dynamic control system for a pipe curtain freezing method provided by the present application selects different numbers of hard spheres, connects the hard spheres with connecting ropes and then vertically places them into inspection holes and monitoring holes. Multiple hard spheres are in a suspended state in the inspection holes and monitoring holes, and each hard sphere corresponds to a depth. The ambient temperature is transmitted to the puncturing mechanism through a temperature sensing rod arranged on the hard sphere. When the ambient temperature is lower than a certain threshold, the puncturing mechanism punctures the liquid storage ball, and the self-generating mechanism generates current based on the action of the puncturing mechanism on the liquid storage ball to power the temperature sensing element. At this time, the temperature sensing element realizes the monitoring of the soil temperature in the corresponding depth area, and the temperature values ​​at different depths in the inspection holes and monitoring holes are monitored in real time to infer the thickness of the frozen wall at different depths, and the temperature field conditions in the frozen area are inverted. The control center adjusts the power of the refrigeration compressor based on the corresponding temperature field conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a structural schematic diagram of a dynamic control system of a pipe curtain freezing method in an embodiment of the present application;

[0018] Figure 2 This is a schematic diagram of the internal structure of a hard sphere in an embodiment of the present application;

[0019] Figure 3 This is a schematic diagram of the layout provided in the embodiment of the present application;

[0020] Description of Figure Numbers:

[0021] 1 connecting tube, 2 closing cover, 3 rope buckle, 4 dividing plate, 5 first area, 6 second area, 7 left collecting net, 8 right collecting net, 9 hard sphere, 10 hemisphere that shrinks when cold, 11 deformable arc wire, 12 piercing needle, 13 temperature sensing rod, 14 cathode, 15 anode, 16 recessed area, 17 liquid storage ball, 18 inspection hole, 19 temperature sensing element, 20 control center, 21 refrigeration compressor. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further elaborated in detail below in conjunction with the drawings and specific embodiments of the specification. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. In the following description, the expression "some embodiments" is related to a subset of all possible embodiments, but it should be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict.

[0023] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present invention. However, it is apparent to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features well known in the art are not described.

[0024] It should be understood that the present invention can be implemented in different forms and should not be interpreted as being limited to the embodiments proposed herein. On the contrary, providing these embodiments will make the disclosure thorough and complete, and the scope of the present invention will be fully conveyed to those skilled in the art. And the purpose of the terms used herein is only to describe specific embodiments and is not intended to be a limitation of the present invention. When used herein, the singular forms of "one", "one" and "said / the" are also intended to include plural forms, unless the context clearly indicates another way. It should also be understood that the terms "compose" and / or "include" when used in this specification determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0025] It should also be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "inside", "outside", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0026] In order to fully understand the present invention, a detailed structure will be proposed in the following description to illustrate the technical solution proposed by the present invention. The optional embodiments of the present invention are described in detail as follows, but in addition to these detailed descriptions, the present invention may also have other implementations.

[0027] At present, the steps of the pipe curtain freezing method construction generally include: drilling holes in the ground and injecting freezing liquid into the soil through these holes, and freezing the soil into a solid state by injecting liquid refrigerant in a specific area around the ground. The liquid refrigerant can be low-temperature salt water or liquid nitrogen, etc., and its function is to reduce the temperature of the soil and freeze it by absorbing heat. During the freezing process, the moisture in the soil will also solidify into ice, increasing the stability of the soil. Subsequently, the soil in the frozen area will form a stable frozen soil layer, which can provide support and prevent soil collapse. When construction is carried out in the frozen area, frozen soil walls or other supporting structures can be used to maintain the stability of the underground space, but in the current construction process of the pipe curtain freezing method, the soil at different depths will freeze unevenly, and temperature sensors need to be laid at different depths to realize temperature detection. The current laying process usually requires distributed optical fiber and energy agencies to continuously power the temperature sensor and realize signal transmission. The laying process is relatively cumbersome, and when the soil at the corresponding depth is not frozen, the temperature sensors at different depths are also working continuously, and their energy consumption is large.

[0028] Based on this, this application provides a dynamic control system for pipe curtain freezing method, please refer to the attached Figures 1 to 3The system includes a refrigeration system and a control center 20. The refrigeration system includes a freezing pipe, a refrigeration compressor 21, and a condenser. The freezing pipe, the refrigeration compressor 21, and the condenser are connected in sequence using a circulation pipeline. A liquid refrigerant is sealed in the circulation pipeline, and the liquid refrigerant flows along the circulation pipeline. The control center 20 is connected to the refrigeration compressor 21 by signal. It also includes a temperature detection device. The temperature detection device includes a plurality of hard spheres 9, each of which is connected by a connecting rope. A liquid storage ball 17, a puncture mechanism, a storage mechanism, and a self-generating mechanism are provided inside the hard sphere 9. The storage mechanism is used to store different liquid storage balls 17. The puncture mechanism is connected to a temperature conduction rod, and the temperature conduction rod extends to the outside of the hard sphere 9. The outer surface of the hard sphere 9 is also detachably provided with a temperature sensing element 19. The self-generating mechanism generates current based on the action of the puncture mechanism on the liquid storage ball 17 to power the temperature sensing element 19. The temperature sensing element 19 is connected to the control center 20 by signal.

[0029] When in use, an inspection hole 18, a monitoring hole, and a freezing hole are set in the area to be frozen, and liquid refrigerant is injected into the freezing hole through the refrigeration system. When the temperature detection device is arranged, different numbers of hard spheres 9 are selected according to the different depths of the inspection hole 18 and the monitoring hole, and the hard spheres 9 are connected with connecting ropes and vertically placed in the inspection hole 18 and the monitoring hole. Multiple hard spheres 9 are in a suspended state in the inspection hole 18 and the monitoring hole, and each hard sphere 9 corresponds to a depth. The ambient temperature is transmitted to the inspection hole 18 and the monitoring hole through the temperature sensing rod 13 set on the hard sphere 9. The puncturing mechanism, when the ambient temperature is lower than a certain threshold, the puncturing mechanism punctures the liquid storage ball 17, and the self-generating mechanism generates current to power the temperature sensing element 19 based on the action of the puncturing mechanism on the liquid storage ball 17. At this time, the temperature sensing element 19 monitors the soil temperature of the corresponding depth area, and calculates the thickness of the frozen wall at different depths by real-time monitoring the temperature values ​​at different depths in the inspection hole 18 and the monitoring hole, and inverts the temperature field conditions of the frozen area. The control center 20 adjusts the power of the refrigeration compressor 21 based on the corresponding temperature field conditions.

[0030] In this embodiment, the hard sphere 9 is a hollow sphere, and the outer wall of the hard sphere 9 is made of plastic material, which has the properties of heat insulation and cold resistance, and can keep the inside of the hard sphere 9 at a constant temperature. The top of the hard sphere 9 is provided with a connecting tube 1 and a closing cover 2 threadedly connected to the connecting tube 1. The closing cover 2 and the bottom of the hard sphere 9 are both provided with a rope buckle 3. The closing cover 2 is used to close the inside of the hard sphere 9 and to connect to the previous hard sphere 9. A partition plate 4 is provided inside the connecting tube 1. The partition plate 4 divides the internal space of the connecting tube 1 into a first area 5 and a second area 6. The bottom of the partition plate 4 is connected to the storage mechanism, and different liquid storage balls 17 are respectively put into the hard sphere 9 from the first area 5 / the second area 6 and are stored by the storage mechanism inside the sphere.

[0031] In one embodiment, the storage mechanism includes a collecting net, which includes a left collecting net 7 and a right collecting net 8. One end of the left collecting net 7 is connected to the partition plate 4, and the other end is connected to the inner wall of one side of the hard sphere 9, and the center of the left collecting net 7 is set below the first area 5. One end of the right collecting net 8 is connected to the partition plate 4, and the other end is connected to the inner wall of the other side of the hard sphere 9, and the center of the right collecting net 8 is set below the second area 6. When the liquid storage ball 17 is dropped into the hard sphere 9 from the first area 5, it just falls into the left collecting net 7. When the liquid storage ball 17 is dropped into the hard sphere 9 from the second area 6, it just falls into the right collecting net 8.

[0032] In one embodiment, the puncturing mechanism includes a cold shrink hemisphere 10, a deformable arc wire 11 and a puncturing needle 12. There are multiple cold shrink hemispheres 10, which are respectively arranged on both sides of the inner wall of the hard sphere 9. Each cold shrink hemisphere 10 is connected to the temperature conduction rod. An elastic wire is fixedly connected between the multiple cold shrink hemispheres 10. The puncturing needle 12 is arranged on the upper half of the elastic wire, one of the puncturing needles 12 is aimed at the left collecting net 7, and the other puncturing needle 12 is aimed at the right collecting net 8.

[0033] The temperature sensing rod 13 transmits the ambient temperature to the cold shrink hemisphere 10, which gradually shrinks based on the principle of thermal expansion and contraction, and at the same time pulls the deformation arc wire 11 to deform it, and uses the piercing needle 12 on the deformation arc wire 11 to pierce the liquid storage ball 17 on the left collecting net 7 / right collecting net 8 respectively, and the liquid in the liquid storage ball 17 flows out and gathers at the bottom of the hard sphere 9.

[0034] In one embodiment, the liquid storage ball 17 includes an aqueous solution electrolyte ball, which enters the left collecting net 7 or the right collecting net 8 from different internal spaces of the connecting tube 1. When the puncture needle 12 punctures the liquid storage ball 17 on the left collecting net 7 / right collecting net 8 respectively, the electrolyte in the aqueous solution electrolyte ball flows out and gathers at the bottom of the hard sphere 9.

[0035] In one embodiment, the self-generating mechanism includes a cathode 14 and an anode 15, both of which are arranged directly below the storage mechanism, and the anode 15 is connected to the cathode 14 through a transmission line, and recessed areas 16 are provided on both sides of the outer surface of the hard sphere 9, and a conductive sheet is provided inside the recessed area 16, and the conductive sheet is connected to the transmission line, and the recessed area 16 is used to accommodate the temperature sensing element 19, and the conductive sheet is used to supply power to the temperature sensing element 19. When the cathode 14 and the anode 15 are immersed in the electrolyte solution, current will be generated on the cathode 14 and the anode 15, and the temperature sensor element will be powered through the conductive sheet.

[0036] Specifically, the temperature sensing element 19 includes a temperature sensor and a wireless communication unit, and the temperature sensor and the wireless communication unit are integrated in a box body. The size of the box body is consistent with the size of the recessed area 16. The temperature sensor is connected to the wireless communication unit signal, and the wireless communication unit is connected to the control center 20 signal.

[0037] In one embodiment, different numbers of hard balls 9 are selected based on the depths of the inspection hole 18 and the monitoring hole to be connected to each other and placed in the inspection hole 18 and the monitoring hole.

[0038] In summary, the dynamic control system of the pipe curtain freezing method disclosed in the present application, when detection is needed, different liquid storage balls 17 are respectively dropped into the interior of the hard sphere 9 from the first area 5 / the second area 6, and are received by the receiving mechanism inside the sphere, and the hard spheres 9 are connected by connecting ropes and vertically placed in the inspection hole 18 and the monitoring hole. Multiple hard spheres 9 are in a suspended state in the inspection hole 18 and the monitoring hole, and each hard sphere 9 corresponds to a depth. The ambient temperature is transmitted to the cold shrinking hemisphere 10 through the temperature sensing rod 13 provided on the hard sphere 9. Based on the principle of thermal expansion and contraction, the cold shrinking hemisphere 10 gradually shrinks, and at the same time, the deformation arc wire 11 is pulled to cause it to deform. The piercing needle 12 on the deformable arc wire 11 is used to pierce the liquid storage ball 17 on the left collecting net 7 / right collecting net 8 respectively, and the electrolyte in the liquid storage ball 17 flows out and gathers at the bottom of the hard sphere 9. When the cathode 14 and the anode 15 are immersed in the electrolyte, current will be generated on the cathode 14 and the anode 15, and the temperature sensor element will be powered by the conductive sheet. At this time, the temperature sensor element 19 realizes the monitoring of the soil temperature in the corresponding depth area, and the temperature values ​​at different depths in the inspection hole 18 and the monitoring hole are monitored in real time to calculate the thickness of the frozen wall at different depths, and the temperature field conditions in the frozen area are inverted. The control center 20 adjusts the power of the refrigeration compressor 21 based on the corresponding temperature field conditions.

[0039] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. The protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A dynamic control system for a pipe curtain freezing method, comprising a refrigeration system and a control center, wherein the control center is connected to the refrigeration system signal, characterized in that: It also includes a temperature detection device, which includes a plurality of hard spheres, each of which is connected by a connecting rope. A liquid storage ball, a puncture mechanism, a storage mechanism and a self-generating mechanism are provided inside the hard sphere. The storage mechanism is used to store different liquid storage balls. The puncture mechanism is connected to a temperature conduction rod, and the temperature conduction rod extends to the outside of the hard sphere. A temperature sensing element is detachably provided on the outer surface of the hard sphere. The self-generating mechanism generates current to power the temperature sensing element based on the action of the puncture mechanism on the liquid storage ball, and the temperature sensing element is connected to the control center signal.

2. A pipe curtain freezing method dynamic control system according to claim 1, characterized in that: A connecting tube and a closing cover threadedly connected to the connecting tube are provided at the top of the hard sphere, rope buckles are provided at the closing cover and the bottom of the hard sphere, a partition plate is provided inside the connecting tube, the partition plate divides the internal space of the connecting tube into a first area and a second area, and the bottom of the partition plate is connected to the storage mechanism.

3. A pipe curtain freezing method dynamic control system according to claim 2, characterized in that: The storage mechanism includes a collecting net, which includes a left collecting net and a right collecting net, one end of the left collecting net is connected to the partition plate, and the other end is connected to the inner wall of one side of the hard sphere, and the center of the left collecting net is set below the first area, one end of the right collecting net is connected to the partition plate, and the other end is connected to the inner wall of the other side of the hard sphere, and the center of the right collecting net is set below the second area.

4. A dynamic control system for pipe curtain freezing method according to claim 3, characterized in that: The puncturing mechanism includes a cold shrinking hemisphere, a deformable arc wire and a puncturing needle. There are multiple cold shrinking hemispheres, which are respectively arranged on both sides of the inner wall of the hard sphere. Each cold shrinking hemisphere is connected to the temperature conduction rod. Elastic wires are fixedly connected between the multiple cold shrinking hemispheres. The puncturing needle is arranged on the upper part of the elastic wire, one of the puncturing needles is aimed at the left collecting net, and the other puncturing needle is aimed at the right collecting net.

5. A pipe curtain freezing method dynamic control system according to claim 4, characterized in that: The liquid storage balls include aqueous solution electrolyte balls, and the aqueous solution electrolyte balls enter the left collecting net or the right collecting net from different internal spaces of the connecting cylinders.

6. A dynamic control system for pipe curtain freezing method according to claim 5, characterized in that: The self-generating mechanism comprises a cathode and an anode, the cathode and the anode are both arranged directly below the storage mechanism, and the anode and the cathode are connected via a transmission line.

7. A dynamic control system for pipe curtain freezing method according to claim 6, characterized in that: The outer surface of the hard sphere is provided with recessed areas on both sides, and conductive sheets are provided inside the recessed areas. The conductive sheets are connected to the transmission line. The recessed areas are used to accommodate the temperature sensing element, and the conductive sheets are used to supply power to the temperature sensing element.

8. A dynamic control system for pipe curtain freezing method according to claim 7, characterized in that: The temperature sensing element includes a temperature sensor and a wireless communication unit, which are integrated in a box body. The size of the box body is consistent with the size of the recessed area. The temperature sensor is connected to the wireless communication unit signal, and the wireless communication unit is connected to the control center signal.

9. A pipe curtain freezing method dynamic control system according to claim 1, characterized in that: Different numbers of hard spheres are selected based on the depths of the inspection holes and the monitoring holes, connected to each other, and placed in the inspection holes and the monitoring holes.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: The computer program includes the pipe curtain freezing method dynamic control system as described in any one of claims 1-9.

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