High-thermal-conductivity water-permeable combined structure energy pile

Abstract

The utility model relates to a kind of high thermal conductivity water-permeable combined structure energy pile, including the prefabricated pile of center, the tubular heat exchanger around fixed on prefabricated pile, high thermal conductivity concrete layer wrapped in the outer periphery of prefabricated pile upper portion and high thermal conductivity water-permeable concrete layer wrapped in the outer periphery of prefabricated pile lower portion.The utility model proposes the design scheme that center sets prefabricated pile, prefabricated pile outer periphery sets high thermal conductivity wrapping layer and high thermal conductivity wrapping layer is divided into the design scheme of two layers different wrapping materials.Upper layer uses high thermal conductivity concrete layer, effectively make up the problem of insufficient heat conduction of water-permeable concrete in dry condition in the prior art, while structural strength is greater, effectively improve the bearing capacity of pile body, lower layer uses high thermal conductivity water-permeable concrete layer, give full play to the heat convection effect of groundwater seepage.The layered design not only realizes the maximization utilization of groundwater thermal resources, more through the complementarity of material performance, completely solve the technical problem of unstable heat exchange efficiency of traditional single material under variable water level condition.

Description

Technical Field

[0001] This utility model relates to the field of building pile foundation and ground source heat pump technology, specifically to a high thermal conductivity and water permeable composite structure energy pile. Background Technology

[0002] Energy piles, a green technology utilizing shallow geothermal sources, involve embedding circulating pipelines within the pile foundation of a building. While meeting the bearing capacity requirements of conventional pile foundations, the pile itself acts as a carrier to achieve heat exchange with shallow geothermal energy. Compared to traditional drilled underground pipes, this increases the contact area between the heat exchanger and the soil, fully utilizing the high volumetric specific heat and thermal conductivity of concrete to improve heat exchange efficiency. It saves underground space and engineering costs, and its design concept aligns with the current development trend of energy conservation, emission reduction, and environmental protection, demonstrating promising development prospects and significant potential for widespread adoption.

[0003] However, traditional energy piles have low thermal conductivity due to the low thermal conductivity of the concrete and cannot fully utilize the thermal convection of groundwater, making it difficult to further improve heat exchange efficiency. Energy piles made of highly thermally conductive permeable concrete greatly increase the contact area between the pile and groundwater, allowing for full utilization of groundwater thermal convection. However, the steel reinforcement in permeable concrete piles is prone to corrosion, making it difficult to meet the durability requirements of the pile foundation. Furthermore, permeable concrete is a typical porous material, and its structural characteristics determine its thermal conductivity under different environmental conditions: when there is no groundwater seepage, its internal pores are filled with air, and the thermal conductivity of air is significantly lower than that of solid materials. This directly results in weak overall thermal conductivity of permeable concrete in dry environments. Therefore, developing new permeable building pile foundations is an urgent technical problem to be solved. Utility Model Content

[0004] The purpose of this invention is to propose a high thermal conductivity and permeable composite structure energy pile to solve the technical problems existing in the prior art.

[0005] The technical solution adopted in this utility model is: A high thermal conductivity and permeable composite structure energy pile includes a precast pile at the center, a tubular heat exchanger fixed around the precast pile, a high thermal conductivity concrete layer wrapped around the upper outer periphery of the precast pile, and a high thermal conductivity and permeable concrete layer wrapped around the lower outer periphery of the precast pile. The bottom of the high thermal conductivity concrete layer is sealed to the top of the high thermal conductivity and permeable concrete layer.

[0006] Preferably, the tubular heat exchanger is a double-helix heat exchanger.

[0007] Preferably, both the high thermal conductivity concrete layer and the high thermal conductivity permeable concrete layer are cylindrical structures with equal outer diameters.

[0008] Preferably, the precast pile is a prestressed concrete solid circular pile, and the ratio of the diameter of the precast pile to the diameter of the high thermal conductivity and water permeability combined structure energy pile is set to 1:2.

[0009] Preferably, the tubular heat exchanger is an HDPE spiral heat exchanger.

[0010] Preferably, the tubular heat exchanger is tied and fixed to the spiral heat exchanger.

[0011] Preferably, the precast pile at the center includes a columnar concrete layer and a reinforcing cage disposed within the columnar concrete layer.

[0012] The beneficial effects of this utility model are: This invention proposes a design scheme with a precast pile at the center and a high thermal conductivity wrapping layer around the pile, the high thermal conductivity wrapping layer consisting of two layers of different wrapping materials. The upper layer uses a high thermal conductivity concrete layer, effectively compensating for the insufficient thermal conductivity of permeable concrete under dry conditions in existing technologies, while also increasing structural strength and effectively improving the bearing capacity of the pile. The lower layer uses a high thermal conductivity permeable concrete layer to fully utilize the thermal convection effect of groundwater seepage. This layered design not only maximizes the utilization of groundwater thermal resources but also, through the complementary properties of the materials, completely solves the technical problem of unstable heat exchange efficiency of traditional single materials under changing water levels. In addition, the reinforcing cage is placed inside the precast pile, which is the main load-bearing component. The precast pile is located at the center of the high thermal conductivity permeable composite structure energy pile, and the tubular heat exchanger is located on the outer periphery of the precast pile. Compared with existing energy piles, the precast pile does not require drilling to introduce groundwater, thus avoiding the defect of easy corrosion of steel bars in traditional permeable concrete piles. The high thermal conductivity wrapping layer and the precast pile share the load, which not only ensures the bearing capacity of the pile foundation, but also ensures the structural durability of the pile body, reduces the later maintenance cost, and has good technical economy and environmental adaptability. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the high thermal conductivity and water permeable combined structure energy pile of this utility model.

[0014] Figure 2 for Figure 1 A schematic diagram of the AA section structure.

[0015] In the diagram: 1. Tubular heat exchanger; 2. Precast pile; 3. High thermal conductivity concrete layer; 4. High thermal conductivity permeable concrete layer; 5. Water outlet; 6. Groundwater level. Detailed Implementation

[0016] The technical solution of this utility model will be further described below with reference to the accompanying drawings and embodiments. The following specific embodiments will help those skilled in the art to further understand this utility model, but do not limit this utility model in any way. It should also be noted that, for ease of description, only the parts related to this utility model are shown in the drawings, not all of them.

[0017] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Example

[0018] A high thermal conductivity and permeable composite energy pile includes a central precast pile 2, a tubular heat exchanger 1 fixed around the precast pile, a high thermal conductivity concrete layer 3 surrounding the upper outer periphery of the precast pile, and a high thermal conductivity and permeable concrete layer 4 surrounding the lower outer periphery of the precast pile. The bottom and top of the high thermal conductivity and permeable concrete layers are sealed together. The tubular heat exchanger 1 is a double-helix heat exchanger with an inlet and an outlet 5. The high thermal conductivity concrete layer 3 is used in areas above the groundwater level, and the high thermal conductivity and permeable concrete layer 4 is used in areas below the groundwater level. During pile embedding, the high thermal conductivity concrete layer 3 and the high thermal conductivity permeable concrete layer 4 are embedded with piles at a dividing line of 6; both the high thermal conductivity concrete layer and the high thermal conductivity permeable concrete layer are circular tubular structures with equal outer diameters; the precast piles are prestressed concrete solid circular piles, and the ratio of the diameter of the precast piles to the diameter of the high thermal conductivity permeable composite structure energy piles is set at 1:2; the tubular heat exchanger is an HDPE material spiral heat exchanger; the tubular heat exchanger is tied and fixed on the spiral heat exchanger; the central precast pile includes a columnar concrete layer and a reinforcing cage (not shown in the figure) located within the columnar concrete layer.

[0019] In this embodiment, the materials used for the precast piles, tubular heat exchangers, high thermal conductivity concrete layers, and high thermal conductivity permeable concrete layers are all existing technologies. In this embodiment, the high thermal conductivity concrete layer is prepared by mixing the following components in parts by weight: 18-19 parts water, 41-42 parts cement, 92-95 parts crushed stone, 54-56 parts sand, 2.5-7.9 parts silicon carbide, and 0.3-0.6 parts water-reducing agent; the high thermal conductivity permeable concrete layer is prepared by mixing the following components in parts by weight: 14.5-15.5 parts water, 41-42 parts cement, 150-155 parts crushed stone, 2.5-7.9 parts silicon carbide, 2.6-2.7 parts reinforcing agent, and 0.7-0.8 parts water-reducing agent. Other existing publicly available components that meet the usage requirements may also be used.

[0020] This embodiment proposes a design scheme with a precast pile at the center and a high thermal conductivity wrapping layer around the precast pile, the high thermal conductivity wrapping layer consisting of two layers of different wrapping materials. The upper layer, used for areas above the groundwater level, uses a high thermal conductivity concrete layer, effectively compensating for the insufficient thermal conductivity of permeable concrete under dry conditions in existing technologies, while also increasing structural strength and effectively improving the bearing capacity of the pile. The lower layer, used for areas below the groundwater level, uses a high thermal conductivity permeable concrete layer to fully utilize the thermal convection effect of groundwater seepage. This layered design not only maximizes the utilization of groundwater thermal resources but also, through the complementary properties of the materials, completely solves the technical problem of unstable heat exchange efficiency of traditional single materials under varying water levels. In addition, the reinforcing cage is placed inside the precast pile, which is the main load-bearing component. The precast pile is located at the center of the high thermal conductivity permeable composite structure energy pile, and the tubular heat exchanger is located on the outer periphery of the precast pile. Compared with existing energy piles, the precast pile does not require drilling to introduce groundwater, thus avoiding the defect of easy corrosion of steel bars in traditional permeable concrete piles. The high thermal conductivity wrapping layer and the precast pile share the load, which not only ensures the bearing capacity of the pile foundation, but also ensures the structural durability of the pile body, reduces the later maintenance cost, and has good technical economy and environmental adaptability.

[0021] The above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Those skilled in the art should understand that it is neither necessary nor possible to exhaustively describe all possible implementations. It should be noted that various modifications or alterations can be made to the device without departing from the concept of this utility model. These all fall within the protection scope of this utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A high thermal conductivity and permeable composite structure energy pile, characterized in that: It includes a precast pile at the center, a tubular heat exchanger fixed around the precast pile, a high thermal conductivity concrete layer wrapped around the upper outer periphery of the precast pile, and a high thermal conductivity permeable concrete layer wrapped around the lower outer periphery of the precast pile. The bottom of the high thermal conductivity concrete layer is sealed to the top of the high thermal conductivity permeable concrete layer.

2. The high thermal conductivity and permeable composite structure energy pile according to claim 1, characterized in that: The tubular heat exchanger is a double spiral heat exchanger.

3. The high thermal conductivity and permeable composite structure energy pile according to claim 1, characterized in that: Both the high thermal conductivity concrete layer and the high thermal conductivity permeable concrete layer are cylindrical structures with equal outer diameters.

4. The high thermal conductivity and permeable composite structure energy pile according to claim 3, characterized in that: The precast pile is a prestressed concrete solid circular pile, and the ratio of the diameter of the precast pile to the diameter of the high thermal conductivity and water permeability combined structure energy pile is set to 1:

2.

5. The high thermal conductivity and permeable composite structure energy pile according to claim 1, characterized in that: The tubular heat exchanger is an HDPE spiral heat exchanger.

6. The high thermal conductivity and permeable composite structure energy pile according to claim 1, characterized in that: The tubular heat exchanger is tied and fixed to the spiral heat exchanger.

7. The high thermal conductivity and permeable composite structure energy pile according to claim 1, characterized in that: The precast pile at the center includes a columnar concrete layer and a steel cage placed within the columnar concrete layer.

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