Ground source heat pump energy supply system arranged under building floor and construction method thereof

Abstract

The application discloses a ground source heat pump energy supply system arranged under a building bottom plate and a construction method thereof, and relates to the field of ground source heat pump energy supply systems; the system comprises a vertical buried pipe assembly, a horizontal buried pipe assembly, a ground source heat pump unit and a BIM collaborative control unit, and the method comprises the following steps: terrain surveying, surveying the terrain and geology of a building to obtain terrain and geology parameter data; BIM modeling, performing BIM modeling according to the surveyed terrain and geology parameters, and determining a virtual path according to design requirements and modeling results, and then converting the virtual path in the BIM model into on-site entity markers; drilling machine debugging and drilling, debugging the drilling machine and then drilling, and drilling in the drilling process. The buried pipe assembly is integrated under the building bottom plate, the layout is optimized in combination with a BIM collaborative control system, and the buried pipe assembly is provided with a self-cleaning function and a waste heat recovery function, so that efficient and energy-saving energy supply is realized, the influence on the surrounding environment is small, and economic and social benefits are remarkable.

Description

Technical Field

[0001] This invention relates to the field of energy, and more particularly to a ground source heat pump energy supply system installed under the foundation slab of a building and its construction method. Background Technology

[0002] A ground source heat pump system is a highly efficient energy supply technology that utilizes the relatively constant temperature of underground soil as a heat source and cold source. Its core principle is to circulate a medium (water or antifreeze) through underground closed-loop pipes. In winter, this medium absorbs heat energy from the soil, which is then heated by the heat pump unit to provide heating for the building. In summer, it transfers indoor heat to the underground soil for cooling. The system consists of underground heat exchange pipes (including vertical and horizontal buried pipes), a heat pump unit (with built-in compressor, evaporator, condenser, etc.), indoor terminal equipment, and a circulating water pump, achieving energy transfer through a closed-loop cycle. Compared to traditional air conditioning, its coefficient of performance (COP) can be increased by 30%-60%, significantly reducing energy consumption.

[0003] Ground source heat pumps are widely used due to their high efficiency and energy saving characteristics, but traditional systems have significant limitations: they require a separate site for laying underground pipes, which not only occupies a large area but also easily conflicts with building foundations, making them difficult to implement in urban core areas where land resources are scarce. At the same time, the existing technology lacks sufficient coordination between underground pipes and building structures, resulting in loose pipe layouts and low space utilization, which not only wastes land resources but also affects heat exchange efficiency due to structural conflicts.

[0004] Therefore, this invention proposes a ground source heat pump energy supply system installed under the building's foundation slab and its construction method. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a ground source heat pump energy supply system installed under the building foundation and its construction method.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A ground source heat pump energy supply system installed under the building's foundation slab includes a vertical buried pipe assembly, a horizontal buried pipe assembly, a ground source heat pump unit, and a BIM collaborative control unit.

[0007] A construction method for a ground source heat pump energy supply system installed under the building's foundation includes the following steps: S01: On-site inspection and "comprehensive assessment of building adaptability".

[0008] This includes the density of loose soil layers in their natural state and under load, the condition of water-bearing soil layers under load, and other characteristics. It also addresses factors affecting construction and the surrounding conditions. These mainly include: the size and shape of the land area; existing and planned buildings or structures; the presence of trees and elevated facilities such as high-voltage power lines; the grade and extent of natural or artificial surface water sources; transportation roads and their surrounding ancillary buildings and underground service facilities; the layout of existing underground pipelines and the status of abandoned systems; the power and water supply conditions required for drilling; and the locations of other possible installation systems.

[0009] S02: BIM modeling optimization "spatial conflict pre-simulation and dynamic parameter association".

[0010] Parametric linkage modeling: The three major elements of "heat and cold load, soil properties, and building structure" are incorporated into the BIM model to achieve dynamic correlation of "trench depth (climate / soil quality), number of boreholes (load / obstacles), and pipeline route (turning point / branch point)". For example, the trench length is automatically adjusted according to the soil moisture content, and the pipeline path is automatically generated to avoid obstacles according to the pile foundation location, avoiding the rework problem of the traditional "design first and then adjust" approach. Coordinate visualization positioning: By using "coordinate stakes + white and gray border lines", the virtual path in the BIM model is converted into on-site entity markers, accurately locking the center, depth and pipeline coordinates of the trench, ensuring that the deviation between subsequent construction and design is ≤5cm (traditional construction deviation often reaches 10-20cm).

[0011] S03: "Dual guarantee of verticality control and environmentally friendly construction" for drilling rig commissioning and drilling.

[0012] High-precision verticality control: The verticality of the drilling rig spindle is monitored in real time using the "vertical plumb line method", with an error requirement of <0.5%L (L is the drilling depth), which is much stricter than the traditional 1% standard; at the same time, "dynamic repair welding of drill bit wear" (repair welding is carried out when wear exceeds 5mm) is used to ensure that the hole diameter is ≥150mm, so as to avoid poor fit of buried pipe and reduced heat exchange efficiency due to drilling tilt or insufficient hole diameter. Pre-construction pollution prevention: Mandatory installation of "1m×1.5m×0.5-1.0m sedimentation tanks", with simultaneous wellhead sealing and dust prevention facilities, to solve the problem of mud overflowing from traditional boreholes polluting the foundation soil and affecting the structural strength of the base plate.

[0013] S04: Vertical buried pipe installation "base plate space reuse and structural coordination".

[0014] "Staggered nesting" layout: Vertical buried pipes are set vertically along the bottom slab, and the pipe piles and building piles are "staggered" (the net distance between piles is adapted to the pile spacing), completely embedded in the soil space under the bottom slab, without occupying additional surface land; at the same time, the buried depth is strictly controlled to "1.5 times the building foundation depth", which not only utilizes the high density soil after the foundation is compacted to improve heat exchange efficiency, but also avoids conflict with the pile foundation structure. Pipe connection and protection process: adopt "double U-shaped elbow + vertical pipe hot melt connection", combined with pressure test after electrofusion connection (to ensure no leakage), and "water-filled sealing cap + 1-2m straight section binding at the head". The former solves the problem of easy leakage of traditional pipe joints, while the latter avoids pipe damage caused by bending during pipe laying and ensures that the pipe fits tightly with the inner wall of the borehole.

[0015] S05: Vertical backfill with "dual objectives of enhanced heat exchange and environmental protection".

[0016] The “three-layer backfilling” process requires three backfillings (first fine sand, second and third composite slurry mixed with phase change materials) to be completed within 12 hours. Phase change materials can improve the soil’s heat storage capacity and solve the problem of heat exchange efficiency decay caused by insufficient thermal conductivity of traditional backfill materials. Environmentally friendly functional design: The backfill mud is not only used for filling, but also plays a role in "groundwater protection" - by filling densely, it blocks the seepage path of surface pollutants along the borehole, and at the same time protects the flow of groundwater when passing through faults / underground rivers, avoiding the damage to the groundwater system caused by traditional construction.

[0017] S06: Pipeline positioning control "high-precision benchmark monitoring system".

[0018] A "dynamic verification benchmark network" was established: temporary benchmarks were set up at a rate of "no less than one every 200m," and were verified simultaneously with pipeline axis control stakes and elevation stakes; for connection points with existing pipelines / structures, coordinates and elevations were forcibly calibrated before construction began. This "high-frequency verification + special verification of connection points" mechanism solved the problem of pipeline misalignment caused by benchmark deviations in traditional positioning, ensuring the accurate layout of dense pipelines under the foundation slab.

[0019] S07: Trench excavation "Layered safety and space protection".

[0020] "Safety layering" parametric design: When the trench depth exceeds 3m, forced layered excavation (each layer ≤2m) is required, and the width of the platform between layers is clearly defined (sloping trench ≥0.8m, straight trench ≥0.5m) to avoid the risk of slope collapse caused by traditional one-time excavation; The "zero interference with surrounding facilities" rule strictly stipulates that "the height of the soil pile should be ≤1.5m and the distance from the trench opening should be ≥0.8m", and fire hydrants, manhole covers and other facilities should not be buried. This solves the problem of pipeline damage or facility failure caused by improper soil piling in traditional construction.

[0021] S08: Horizontal buried pipe installation "Compact layout and protective details".

[0022] The compact design of "rectangular array + equal length piping" means that the pipes are arranged in a rectangular array with a spacing of 30-50cm (40% less than the traditional spacing), and the sum of the length of the input pipe and the output pipe of each hot well is equal to ensure balanced water flow resistance; at the same time, the burial depth of the main pipeline is strictly controlled to be "below the frost line + soil cover ≥1000mm" to avoid damage from frost heave in winter. The "full-process protection" process uses non-metallic ropes for pipe laying (to avoid metal friction damage), pipe opening sealing protection (sealing during intermittent construction), and temporary opening measures to prevent debris, thus solving the problem of "time-sensitive connection strength control" in traditional S09: pipe connection and pressure testing.

[0023] The principle of "pressure testing 24 hours after heat fusion connection" is clearly defined. This ensures the strength of the interface by allowing for a natural curing period of 24 hours, avoiding the hidden cracking caused by premature pressure testing in the traditional method. This ensures the reliability of the connection of the pipeline under the base plate (which is extremely difficult to maintain) from a time perspective.

[0024] S10: Horizontal pipe backfilling: "Dual objectives of protection and fit" The "layered protection" system first lays a 10-20cm layer of fine sand at the bottom (to prevent stones from damaging the pipes), and then lays two warning tapes (to warn of potential damage during later excavation), solving the problem of pipe damage caused by foreign objects or later construction during traditional backfilling. “Structural Coordination” Backfilling: After simulating the avoidance of the bottom slab reinforcement through BIM, steel-plastic transition joints are used to connect the pipes. During backfilling, “layer-by-layer compaction + close contact with the pipes” is carried out to ensure the heat conduction efficiency between the soil and the pipes, and to avoid spatial conflicts between the reinforcement and the pipes.

[0025] S11: Heat pump unit installation "integrated space saving".

[0026] "Embedded design": The unit is integrated into the building equipment layer and has a built-in rotating cleaning component (which is driven by water flow and then stored in the cavities at both ends without taking up extra space), solving the problem of traditional cleaning devices occupying room space. "Functional reuse" circulation system: The waste heat recovery module shares the circulation path with the domestic hot water pipes, eliminating the need for additional hot water pipes and saving more than 30% of the pipe space compared to traditional systems.

[0027] S12: Temperature monitoring with "full-range perception and dynamic feedback".

[0028] A "distributed monitoring network" is constructed: sensors are installed at the bottom of vertical pipes, the turning points of horizontal pipes, and key locations on the base plate. Each manifold area is monitored independently, and the data is fed back to the BIM system in real time. This "full coverage + zoned control" mechanism can accurately capture changes in the soil temperature field, providing a basis for adjusting system parameters and avoiding the adjustment lag problem caused by traditional "single-point monitoring".

[0029] S13: BIM Collaborative Control "Full Lifecycle Spatial Optimization".

[0030] Before construction: Simulate the relative positions of pipelines, pile foundations, and bottom slab reinforcement to optimize the layout in advance and avoid spatial overlap; During construction: Real-time updates of installation data and dynamic correction of deviations (such as automatic warnings when the actual coordinates of the pipeline deviate from the model by more than 5cm). Operation phase: Unit parameters are optimized by combining temperature monitoring data (such as adjusting the circulation flow rate based on soil temperature). This full-stage BIM collaboration from design to construction to operation maximizes the utilization of the limited space under the foundation, improving land utilization by more than 60% compared to traditional systems.

[0031] The site survey assesses the suitability of the construction site based on the exploration results of test boreholes or local geological conditions. This includes the density of loose soil layers in their natural state and under load, the condition of water-bearing soil layers under load, and other characteristics. It also addresses factors affecting construction and the surrounding conditions, including: the size and shape of the land area; existing and planned buildings or structures; the presence of trees and overhead facilities such as high-voltage power lines; the grade and extent of natural or artificial surface water sources; transportation roads and their surrounding ancillary buildings and underground service facilities; the layout of existing underground pipelines and the status of abandoned systems; the power and water supply required for drilling; and the locations of other potential installation systems.

[0032] BIM modeling optimizes the layout of pipelines and building structures, and simultaneously prepares qualified materials and equipment. Trench depth considers the impact of climate, soil type, and whether trenching is done manually or mechanically. Trench length considers the available surface area, heating and cooling loads, the number of pipelines buried in the trench, soil type, and soil moisture content. The depth and number of vertical boreholes consider the available surface area, obstacles, heating and cooling loads, and soil and rock types. Pipeline turning points, branch points, and slope change points are determined, and the pipeline route is established accordingly. Coordinate stakes are driven at these points to mark the trench center and depth. A straight line is drawn along the stakes, and lime is sprinkled along the edge. The coordinate positions of the pipeline are then determined.

[0033] Level the drilling rig and check the verticality of its spindle using a plumb line method, ensuring the verticality error is less than 0.5%L. Before and during construction, frequently check the drill bit diameter to ensure it is not less than 150mm. Repair any wear exceeding 5mm by welding promptly to ensure the drill bit diameter meets the design hole diameter requirements. After the drilling rig reaches the designated drilling position, excavate a sedimentation tank 1m wide, 1.5m long, and 0.5–1.0m deep next to the rig. Drilling can only begin after the sedimentation tank is excavated and the wellhead sealing and dust control facilities are properly installed.

[0034] The vertical buried pipe assembly consists of double U-shaped elbows and vertical pipes connected by heat fusion. The system is divided into zones, with each loop consisting of four holes, and equipped with an outdoor manifold. High-density polyethylene (HDPE) pipes are used, with PE pipes connecting the manifold and the manifold. The length of the PE pipes is strictly controlled to ensure that the length of each pipe is the design depth of the vertical hole. The U-shaped pipe fittings are electrofused to the PE pipes and pressure tested to ensure the integrity of the U-shaped pipes and prevent leakage. Water is added and capped to prevent sand and other contaminants from entering the U-shaped pipes during installation and storage. The front of the U-shaped pipe is tied to ensure that the head of the U-shaped pipe is 1m-2m straight to facilitate installation. The vertical buried pipes are installed vertically along the building's foundation slab, with a burial depth of not less than 1.5 times the building's foundation depth. The pipe piles are staggered with the building's pile foundations, and the net distance between the piles is adapted to the pile foundation spacing, utilizing the soil space below the foundation slab to achieve zero additional land occupation.

[0035] Vertical backfilling is a crucial step in the construction of underground pipe heat exchangers. After drilling and installing the U-shaped pipe, backfill slurry is injected into the borehole. This slurry sits between the buried pipe and the borehole wall, enhancing heat exchange between the pipe and the surrounding soil and rock. It also prevents surface water from seeping into the ground through the borehole, protecting groundwater from surface contaminants and preventing cross-contamination between different aquifers. Inadequate backfilling along the length of the buried pipe weakens heat transfer, affecting the performance of the underground heat exchanger. Besides these technical reasons, environmental factors also play a role. When vertical pipes cross faults or underground rivers, backfilling protects the hydraulic properties of the underground river, prevents migration between groundwater layers, and prevents surface or near-surface contaminants from seeping downwards along the pipe. Each borehole requires three backfilling and sealing operations after installation, completed within 12 hours. The backfill material is a composite slurry mixed with phase change materials, and a pressure test is conducted before grouting to confirm no leaks.

[0036] Temporary benchmarks and pipeline axis control stakes should be set up for easy observation and must be firmly secured, with protective measures in place. There should be no fewer than one temporary benchmark every 200 meters along the trenched pipeline laying route. Temporary benchmarks, pipeline axis control stakes, and elevation stakes must be verified before use and should be checked frequently. The planar position and elevation of existing pipelines, structures, etc., connecting with this project should be measured before construction begins.

[0037] When trenches are excavated to a considerable depth, the depth of each layer should be reasonably determined. If the trench depth exceeds 3m, it should be excavated in layers, with each layer not exceeding 2m in depth. The width of the platform between layers for manually excavated multi-layer trenches should be: not less than 0.8m for sloping trenches, not less than 0.5m for straight trenches, and not less than 1.5m for wellpoint equipment installation. The excavation must not affect the safety of buildings, pipelines, or other facilities; fire hydrants, pipe valves, storm drains, survey markers, and manhole covers of various underground pipelines must not be buried, and their normal use must not be impeded. When manually excavating trenches, the height of the soil pile should not exceed 1.5m, and the distance from the edge of the trench opening should not be less than 0.8m.

[0038] The horizontal buried pipe assembly adopts a compact rectangular array arrangement with a pipe spacing of 30-50cm. The sum of the lengths of the input and output pipes corresponding to each heat well is equal. The outdoor main pipeline is laid directly with PE pipes, with the burial depth below the frost line and the soil cover thickness above the pipe not less than 1000mm. A 10-20cm thick fine sand cushion layer is laid under the horizontal pipeline, and a 100mm thick fine sand cushion layer is laid outside the foundation pit with a slope of not less than 0.002. The manifold slopes towards the highest point of the indoor exhaust. When moving the PE pipes into the trench, the pipe material must not be damaged, and the surface must not have obvious scratches. Non-metallic ropes are used for lowering the pipes. The pipes should be arranged along the trench edge in the direction of pipeline laying. For laying and connection intervals that are long or at the end of each project, the pipe openings should be sealed and protected. When it is necessary to temporarily open the pipe openings, measures must be taken to ensure that soil, sand, and other debris do not enter the pipeline, and the surrounding environment of the pipe openings must be kept clean.

[0039] To prevent breakage and kinking during pipeline installation, after hot-melt connection is completed according to the construction operation procedure, a water pressure test should be carried out 24 hours later. The next procedure can only be carried out after the test is passed.

[0040] The backfill material at the bottom of the horizontal buried pipe must be fine-grained, loose, and uniform, and should not contain stones or clods. A 10-20cm thick sand cushion layer should be backfilled. After the sand cushion layer is completed, two warning tapes should be laid to prevent damage to the PE pipe during subsequent excavation. Backfilling must be done layer by layer, and the pipe must not be damaged. The backfilling and compaction process should be uniform, and the backfill soil should be in close contact with the pipe. After the trench is cleaned, it should be leveled and compacted, with a density not lower than the original foundation. Steel-plastic transition joints should be used for pipe connections, and BIM simulation should be used to avoid the bottom slab reinforcement to reduce spatial conflicts.

[0041] The ground source heat pump unit is integrated into the building equipment floor and has a built-in rotating cleaning component that can be driven by water flow to rotate and reciprocate. After cleaning, it is stored in the cavities at both ends of the unit. The unit is equipped with a waste heat recovery module, which uses the warm water after heat exchange to supply domestic hot water and shares the circulation path with the system pipeline to save space.

[0042] A temperature monitoring network is established, with temperature sensors installed at the bottom of vertical buried pipes, at the bends of horizontal pipes, and at key locations on the building's foundation. Each manifold area is equipped with a soil temperature monitoring system, which monitors the temperature in real time and feeds it back to the BIM system for dynamic adjustment.

[0043] Before construction, the BIM collaborative control system simulates the relative positions of pipelines, pile foundations, and bottom slab reinforcement to optimize the layout and avoid spatial overlap; during construction, it updates installation data in real time to correct deviations; and during operation, it combines temperature data to optimize parameters and maximize space utilization.

[0044] The beneficial effects of this invention are as follows: This invention integrates underground pipe components under the building's foundation slab, optimizes the layout using a BIM collaborative control system, and is equipped with self-cleaning and waste heat recovery functions, achieving efficient and energy-saving energy supply with minimal impact on the surrounding environment and significant economic and social benefits. Attached Figure Description

[0045] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application. In the drawings: Figure 1 This is a flowchart illustrating a construction method for a ground source heat pump energy supply system installed under the building's foundation, as proposed in this invention. Detailed Implementation

[0046] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0047] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0048] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0049] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0050] In addition, the term "multiple" should mean two or more.

[0051] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0052] During the construction preparation phase, BIM modeling simulated the location of the pile foundation (3m spacing) and 914-hole pipe piles under the base slab. The pipe piles were arranged alternately at 1.2m intervals and were all embedded in the soil under the base slab, requiring no external land. The incoming PE pipes (De32, De63) underwent appearance and pressure tests and met the PE100SDR11 standard.

[0053] During vertical underground pipe construction, the borehole diameter error should be ±5mm, and the verticality ≤0.5%. Double U-shaped pipes should be manually inserted, and the pipe markings should ensure a burial depth of 1.5 times the foundation depth. After a water pressure test with a pressure drop ≤3% after 30 minutes of stabilization, backfilling should be carried out three times within 12 hours: the first time with fine sand, the second and third times with composite slurry mixed with phase change materials, and in dense soil and rock areas, water-settled foundation material. A pressure test should be conducted before backfilling to ensure no leakage.

[0054] Horizontal buried pipe construction is completed before the foundation layer. Trenching is done in layers (each layer ≤ 2m), and compacted after cleaning. Pipes are laid in a rectangular array with 30cm intervals, followed by a 15cm fine sand layer (100mm outside the pit) with a 0.002 slope. Ventilation devices are installed at high points. Pipes are connected using steel-plastic transition joints. The main outdoor pipe is buried below the frost line, with a 1000mm soil cover on top. Pressure is maintained after installation. Backfilling is done using materials free of sharp objects, with simultaneous compaction on both sides, a height difference ≤ 300mm, and manual backfilling at the pipe armholes. Work continues only after all accumulated water has been drained.

[0055] The ground source heat pump unit is installed in the underground equipment layer, and the connecting pipes are shortened by 30% through BIM optimization, reducing space occupation. During commissioning, the BIM system monitors the temperature and pressure of each area (each manifold is monitored independently), and adjusts the circulation pump frequency to ensure uniform heat exchange. The rotating cleaning component is activated periodically for descaling, and the waste heat recovery module supplies domestic hot water.

[0056] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A ground source heat pump energy supply system installed under the foundation slab of a building, characterized in that, It includes vertical buried pipe assemblies, horizontal buried pipe assemblies, ground source heat pump units, and BIM collaborative control units.

2. A construction method for a ground source heat pump energy supply system installed under the foundation slab of a building, characterized in that, It includes the following steps: S01: Topographic survey, to conduct a topographic and geological survey of the building and obtain topographic and geological parameter data; S02: BIM modeling. Based on the surveyed geological and topographical parameters, BIM modeling is performed. Virtual paths are determined according to design requirements and modeling results. Then, the virtual paths in the BIM model are converted into on-site entity markers. S03: Drilling rig debugging and drilling. After debugging the drilling rig, drilling is carried out. During the drilling process, the verticality of the drilling rig spindle is monitored in real time using the vertical plumb line method, and the wear of the drilling bit is also monitored in real time. S04: Vertical buried pipe installation, the vertical buried pipe is set along the vertical direction of the base plate, and the pipe piles are arranged alternately with the building pile foundation; S05: Vertical backfilling, using three-layer backfilling, the first layer uses fine sand backfilling, and the second and third layers use composite mud slurry with added materials for backfilling. S06: Pipeline positioning control, calibrating the pipeline positioning position before construction begins, and implementing pipeline positioning position detection during construction; S07: Trench excavation. Trench excavation shall be carried out according to the marked position of the horizontal buried pipe, and warning tape shall be set on both sides of the trench excavation. S08: For horizontal buried pipe installation, first lay a fine sand cushion layer at the bottom of the trench, and then install the horizontal buried pipe in the excavated trench. S09: Pipeline connection and pressure test, perform heat fusion connection on the pipeline, and perform pressure test on the pipeline after the heat fusion connection is stable; S10: Horizontal pipe backfilling, using backfill material to backfill and compact the trench of the horizontal pipe; S11: Heat pump unit installation: A machine room is set up inside the building, and the heat pump unit is installed in the machine room. At the same time, the heat pump unit is connected to the pipeline. S12: Temperature detection. Temperature sensors are installed at the bottom of vertical pipes, at the bends of horizontal pipes, and on the floor. Each manifold area is monitored independently, and the monitoring data is fed back to the BIM collaborative control unit in real time.

3. The construction method of a ground source heat pump energy supply system installed under the building foundation slab according to claim 2, characterized in that, In step S01, the survey content includes: Based on the exploration results of the test wells or local geological conditions, conduct on-site investigations, including the density of loose soil layers in their natural state and under load, and the condition of water-bearing soil layers under load. The survey of factors affecting construction and the conditions around the construction site includes the size and shape of the land, existing and planned buildings or structures, the presence of trees and elevated facilities, the grade and extent of natural or artificial surface water sources, traffic roads and their surrounding ancillary buildings and underground service facilities, the layout of existing underground pipelines and the status of abandoned systems, and the power and water supply conditions required for drilling.

4. The construction method of a ground source heat pump energy supply system installed under the building foundation slab according to claim 2, characterized in that, Step S02 includes: S021: Determine the pipeline turning points, branch points, and slope change points based on the survey results and design requirements, and determine the pipeline route accordingly; S022: Drive coordinate stakes at the determined points to mark the center of the trench and the trench depth; S023: Straighten the line along the stake, sprinkle lime along the edge, and determine the coordinate position of the pipeline.

5. A construction method for a ground source heat pump energy supply system installed under the building foundation slab according to claim 2, characterized in that, In step S03, the drilling rig is leveled using the vertical plumb line method, and the verticality of the drilling rig spindle is less than 0.5%L. Before and during construction, the drill bit diameter is checked to ensure it is not less than 150mm. If the wear exceeds 5mm, it is repaired by welding. After the drilling rig reaches the designated drilling position, a sedimentation tank is opened next to the drilling rig. After the sedimentation tank is excavated, the wellhead is sealed and dustproof facilities are installed before drilling begins.

6. A construction method for a ground source heat pump energy supply system installed under the building foundation slab according to claim 2, characterized in that, In step S04, the vertical buried pipe assembly is composed of a double U-shaped elbow and a vertical pipe connected by heat fusion, and the burial depth of the vertical buried pipe assembly is not less than 1.5 times the depth of the building foundation.

7. A construction method for a ground source heat pump energy supply system installed under the building foundation slab according to claim 2, characterized in that, In step S07, when the trench excavation depth exceeds 3m, layered excavation is adopted, with each layer having a depth of ≤2m, and a platform is left between layers. The width of the platform is: ≥0.8m for sloping trenches and ≥0.5m for straight trenches.

8. A construction method for a ground source heat pump energy supply system installed under the building foundation slab according to claim 2, characterized in that, In step S08, the horizontal buried pipes are arranged in a rectangular array with a spacing of 30-50cm, the pipe burial depth is below the frost line and the thickness of the soil covering the top of the pipe is not less than 1000mm.

9. A construction method for a ground source heat pump energy supply system installed under the building foundation slab according to claim 2, characterized in that, In step S09, the pressure test should be carried out at least 24 hours after the pipeline is heat-fused.

10. A construction method for a ground source heat pump energy supply system installed under the building foundation slab according to claim 2, characterized in that, In step S11, the ground source heat pump unit has a built-in rotating cleaning component that can be driven by water flow to rotate and reciprocate, and after cleaning, it is stored in the cavities at both ends of the unit; the unit is equipped with a waste heat recovery module, which uses the warm water after heat exchange to supply domestic hot water.

Images