Water pressure self-balancing method and system for anti-floating and anti-sinking pre-embedded bottom plate of building in complete period

Abstract

The invention relates to the technical field of foundation pit engineering, and particularly discloses a building full-cycle anti-floating and anti-sinking embedded type bottom plate water pressure self-balancing method and system.The building anti-floating and anti-sinking embedded type system comprises an enclosure structure, a foundation bottom plate, a frame supporting structure and pumping and draining equipment; the frame supporting structure comprises a plurality of settlement control units fixed to one another. When the underground water level rises, water is pumped out by the pumping and draining equipment and poured into a deep aquifer outside the pit, and shear failure caused by too large buoyancy of a building bottom plate due to increase of pore water pressure is prevented; when the risk of differential settlement of the building is caused by water level drop of the aquifer due to dewatering of a newly-built foundation pit around the building, water in the deep aquifer is pumped out to implement recharge supply on the stratum of the building, stratum deformation and differential settlement are reduced, and soil stress balance is maintained; the system supports flexible water pumping or recharging operation on a plurality of settlement control units and a single-layer or multi-layer aquifer, stratum deformation is effectively controlled, and uneven settlement of a building structure is restrained.

Description

Technical Field

[0001] This invention relates to the field of foundation pit engineering technology, and in particular to a pre-embedded base slab water pressure self-balancing method and system for anti-buoyancy and anti-sinking throughout the building life cycle. Background Technology

[0002] In foundation pit engineering, dynamic changes in groundwater level are a major factor leading to foundation settlement or buoyancy failure of the foundation slab. Traditional techniques rely on independent dewatering wells or recharge wells, which have the following limitations:

[0003] Passive response: The system can only initiate remedial measures after the water level becomes abnormal, lacking real-time sensing and proactive control capabilities;

[0004] Single function: The pumping and reinjection facilities are separate, and the working mode cannot be dynamically switched according to the rise and fall of the water level;

[0005] Poor coordination: It is difficult to achieve coordinated control of multiple aquifers and coordinated management of multiple settlement units;

[0006] Insufficient intelligence: There is a lack of intelligent decision-making mechanisms based on the self-stabilizing target of formation stress.

[0007] Therefore, there is an urgent need for a method and system for controlling ground stress that can intelligently sense, dynamically make decisions, and achieve multi-source coordination, so as to control the settlement of building foundations and thus eliminate the structural risks caused by water level fluctuations. Summary of the Invention

[0008] The purpose of this invention is to provide a pre-embedded water pressure self-balancing method and system for building anti-buoyancy and anti-settlement throughout the entire building life cycle. By actively regulating groundwater, it maintains the effective stress balance of the soil and prevents buoyancy damage and uneven settlement of the building foundation.

[0009] To achieve the above objectives, this invention provides a method for self-balancing water pressure in a pre-embedded foundation slab for anti-buoyancy and anti-sinking throughout the building's lifecycle, comprising the following steps:

[0010] Install pumping equipment and ground water storage tanks, so that at least two pipelines in the pumping equipment are respectively connected to the two aquifers at the bottom of the foundation pit, and the two aquifers are separated by at least one weakly permeable layer.

[0011] Real-time monitoring of the soil pressure status of the uppermost aquifer at the bottom of the foundation pit;

[0012] The rise and fall of the groundwater level is determined by the monitored pressure value. When the monitored pressure value is abnormal, the groundwater in the uppermost aquifer is pumped or recharged: when the pressure value exceeds the set threshold, the groundwater level rises and the groundwater in the aquifer at the bottom of the foundation pit is pumped; when the pressure value is lower than the set threshold, the groundwater level falls and the groundwater in the aquifer at the bottom of the foundation pit is recharged.

[0013] Preferably, when the groundwater in the aquifer at the bottom of the foundation pit is pumped out, the pumped water is discharged to a surface reservoir and / or an aquifer below the weakly permeable layer; when the groundwater in the aquifer at the bottom of the foundation pit is recharged, the recharged water source comes from the pumped water stored in the surface reservoir and / or from the aquifer below the weakly permeable layer.

[0014] The present invention also provides a pre-embedded system for preventing buoyancy and sinking in buildings, including a retaining structure set in the inner wall of the foundation pit, and a foundation slab poured at the bottom of the foundation pit;

[0015] Also includes:

[0016] A frame support structure is installed inside the foundation pit. The edge of the frame support structure contacts the inner wall of the enclosure structure to provide support. The bottom of the frame support structure extends to the bottom of the foundation slab, and the frame support structure is hollow to form a channel for groundwater flow.

[0017] A pumping device, wherein the pumping device is connected to the frame support structure;

[0018] A surface water storage tank, which is connected to the pumping equipment;

[0019] The frame support structure includes multiple settlement control units, adjacent settlement control units are fixedly connected, and the side wall of the settlement control unit located at the edge is in contact with the inner wall of the enclosure structure.

[0020] Preferably, the settlement control unit includes a three-dimensional frame structure composed of several hollow beams and columns; several hollow beams and columns located at the bottom of the three-dimensional frame structure are arranged below the foundation slab and in contact with the soil layer at the bottom of the foundation pit; several seepage pipes are connected between a pair of parallel hollow beams and columns located at the bottom, and a filter layer is provided at the bottom of the seepage pipes, through which the seepage pipes are connected to the soil layer at the bottom of the foundation pit; a water conveying pipe is provided inside the vertically arranged hollow beams and columns, and the water conveying pipe is connected to the pumping equipment.

[0021] Preferably, a pressure detection unit is provided between the surface of the soil layer at the bottom of the foundation pit and the hollow beam column located at the bottom.

[0022] Preferably, the pressure detection unit includes a plurality of pressure sensors evenly arranged.

[0023] Preferably, the filter layer comprises a metal filter screen and a geotextile arranged sequentially from top to bottom.

[0024] Preferably, the retaining structure is an engineering pile and / or a diaphragm wall.

[0025] Preferably, the pumping equipment includes a pumping station, which is connected to the hollow beam column through the water supply pipe, and is also connected to the ground water storage tank;

[0026] The pumping equipment also includes a deep well, and the pumping station is connected to the aquifer below the foundation slab through pipelines in the deep well.

[0027] Preferably, both the inlet and outlet ends of the pump station are equipped with solenoid valves.

[0028] Compared with the prior art, the present invention has the following advantages and technical effects:

[0029] 1. When the groundwater level rises, this invention uses a settlement control unit and pumping equipment to extract water and inject it into the deep aquifer outside the pit, preventing the increased pore water pressure from causing excessive buoyancy on the building's foundation and resulting in shear failure. When dewatering of a new foundation pit around the building causes the aquifer water level to drop, posing a risk of uneven settlement to the building, water from the deep aquifer is extracted and recharged into the building's stratum to reduce stratum deformation and uneven settlement, maintaining the effective stress balance of the soil. Through real-time monitoring and dynamic pumping, the invention actively maintains the stress balance of the stratum.

[0030] 2. This invention features an integrated pumping and reinjection design, supporting two-way operation mode switching;

[0031] 3. The present invention enables multiple settlement control units to flexibly carry out pumping or recharge operations in single or multiple aquifers, effectively controlling stratum deformation and suppressing uneven settlement of building structures. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a structural schematic diagram of the pre-embedded anti-buoyancy and anti-sinking system for buildings according to the present invention;

[0034] Figure 2 This is a cross-sectional view of the settlement control unit of the present invention;

[0035] Figure 3 This is a top view of the pre-embedded anti-buoyancy and anti-sinking system for buildings according to the present invention;

[0036] Figure 4 This is a schematic diagram of the arrangement of the filter layer of the present invention;

[0037] Figure 5This is a schematic diagram of water level regulation during the building operation and maintenance phase of this invention;

[0038] Figure 6 This is a schematic diagram of water level adjustment during the newly excavated foundation pit stage of the present invention;

[0039] In the diagram: 1. Pressure sensor; 2. Drainage pipe; 3. Hollow beam column; 4. Water supply pipe; 5. Enclosure structure; 6. Settlement control unit; 7. Filter layer. Detailed Implementation

[0040] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other. The described embodiments are merely some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] This invention provides a method for self-balancing water pressure in a pre-embedded foundation slab for anti-buoyancy and anti-sinking throughout the building's lifecycle, comprising the following steps:

[0042] Install pumping equipment and ground water storage tanks, so that at least two pipelines in the pumping equipment are respectively connected to the two aquifers at the bottom of the foundation pit, and the two aquifers are separated by at least one weakly permeable layer.

[0043] Real-time monitoring of the soil pressure status of the uppermost aquifer at the bottom of the foundation pit;

[0044] The rise and fall of the groundwater level is determined by the monitored pressure value. When the monitored pressure value is abnormal, the groundwater in the uppermost aquifer is pumped or recharged: when the pressure value exceeds the set threshold, the groundwater level rises and the groundwater in the aquifer at the bottom of the foundation pit is pumped; when the pressure value is lower than the set threshold, the groundwater level falls and the groundwater in the aquifer at the bottom of the foundation pit is recharged.

[0045] To further optimize the scheme, when pumping groundwater from the aquifer at the bottom of the foundation pit, the pumped water is discharged to a surface reservoir and / or an aquifer below the weakly permeable layer; when recharging groundwater from the aquifer at the bottom of the foundation pit, the recharge water source comes from the pumped water stored in the surface reservoir and / or from the aquifer below the weakly permeable layer.

[0046] like Figures 1 to 6 As shown, the present invention also provides a pre-embedded system for building anti-buoyancy and anti-sinking, including a retaining structure 5 set in the inner wall of the foundation pit, and a foundation slab poured at the bottom of the foundation pit;

[0047] Also includes:

[0048] A frame support structure is installed inside the foundation pit. The edge of the frame support structure contacts the inner wall of the retaining structure 5 to provide support. The bottom of the frame support structure extends to the bottom of the foundation slab, and the frame support structure is hollow to form a channel for groundwater flow.

[0049] The extraction and drainage equipment is connected to the frame support structure.

[0050] A surface water storage tank, which is connected to pumping equipment;

[0051] The frame support structure includes multiple settlement control units 6, adjacent settlement control units 6 are fixedly connected, and the side wall of the settlement control unit 6 located at the edge is in contact with the inner wall of the enclosure structure 5.

[0052] In use, after the construction of the retaining structure 5 is completed, a settlement control unit 6 is erected. Several settlement control units 6 form a frame support structure, which supports the inner wall of the retaining structure 5, preventing displacement and deformation. Subsequently, the foundation pit bottom slab and other main structures are poured. When the groundwater level rises, the water level in the soil layer at the bottom of the foundation pit rises, and water enters the settlement control unit 6 and is pumped out by the pumping equipment. When the groundwater level drops, the soil layer at the bottom of the foundation pit collapses, and the pumping equipment recharges water from the surface reservoir or the aquifer below the weakly permeable layer into the soil layer at the bottom of the foundation pit. When the water levels in the corresponding foundation soil layers at the bottom of multiple settlement control units 6 are inconsistent, pumping or recharge operations are carried out on each settlement control unit 6 respectively, ultimately achieving water level control of the soil layer at the bottom of the foundation pit and preventing the foundation pit bottom slab from arching and deforming due to soil pressure and water buoyancy.

[0053] Further optimization of the scheme: the settlement control unit 6 includes a three-dimensional frame structure composed of several hollow beams and columns 3; several hollow beams and columns 3 located at the bottom of the three-dimensional frame structure are set below the foundation slab and in contact with the soil layer at the bottom of the foundation pit; several seepage pipes 2 are connected between a pair of parallel hollow beams and columns 3 located at the bottom, and a filter layer 7 is set at the bottom of the seepage pipes 2, and the seepage pipes 2 are connected to the soil layer at the bottom of the foundation pit through the filter layer 7; a water conveying pipe 4 is installed inside the vertically set hollow beams and columns 3, and the water conveying pipe 4 is connected to the pumping equipment.

[0054] The seepage pipe 2 is provided with several connecting holes. The seepage pipe 2 is in contact with the soil layer at the bottom of the foundation pit. After the water level in the soil layer rises, it can enter the interior of the hollow beam column 3 through the seepage pipe 2. The water conveying pipe 4 is set inside the hollow beam column 3. The water inside the hollow beam column 3 can be pumped out by the pumping equipment and discharged to the ground water storage tank or deep aquifer.

[0055] Similarly, when the soil at the bottom of the foundation pit collapses due to the drop in water level, the water in the ground reservoir or deep aquifer is pumped back into the hollow beam column 3 by the pumping equipment, so that the water level in the water-scarce area rises and the settlement caused by the collapse of the soil is prevented.

[0056] To further optimize the design, a pressure detection unit was installed between the surface of the soil layer at the bottom of the foundation pit and the hollow beam column 3 located at the bottom.

[0057] The design was further optimized so that the pressure detection unit includes several pressure sensors 1 evenly arranged.

[0058] Pressure sensor 1 can detect the pressure of the soil layer at the bottom of the foundation pit on the foundation slab in real time, and determine the timing of pumping or recharge.

[0059] The design was further optimized so that filter layer 7 includes a metal filter screen and geotextile arranged sequentially from top to bottom.

[0060] The scheme was further optimized, and the retaining structure 5 was constructed as engineering piles and / or diaphragm walls.

[0061] The scheme was further optimized, and the pumping equipment included a pumping station. The pumping station was connected to the hollow beam column 3 through the water supply pipe 4, and the pumping station was also connected to the ground water storage tank.

[0062] The pumping equipment also includes deep wells, and the pumping station is connected to the aquifer below the foundation slab through pipelines inside the deep wells.

[0063] The design was further optimized by installing solenoid valves at both the inlet and outlet ends of the pump station.

[0064] To further optimize the scheme, the hollow beams and columns 3 of the adjacent settlement control unit 6 are connected.

[0065] With this setup, when water from the water-rich area moves into the hollow beam column 3, it is connected to the adjacent hollow beam column 3, allowing the water to move into the water-poor area. The water then diffuses into the soil in the water-poor area through the seepage pipe 2, resulting in a uniform water level distribution within the overall soil layer of the foundation. This eliminates the need for manual control and avoids uneven settlement of the foundation.

[0066] Compared to traditional technologies, the hollow beam column 3 of this invention is installed at the bottom of the foundation pit, which can limit the deformation and water supply at the bottom of the retaining structure 5. The hollow beam column 3 has a hollow cavity inside, and the seepage pipe 2, hollow beam column 3 and water supply pipe 4 are interconnected. The water volume or on / off is controlled by a solenoid valve. The hollow beam column 3 is connected to the ground surface through a pump station and water supply pipe 4. When the pressure at the bottom of the foundation pit reaches its near-critical value, groundwater seeps into the seepage pipe 2, which, in conjunction with the hollow beam column 3, is pumped to the surface through the water delivery pipe 4. This not only limits the deformation of the retaining structure 5 but also relieves pressure at the bottom of the foundation pit. When the groundwater level drops, groundwater can be recharged through the water delivery pipe 4 and the seepage pipe 2, preventing settlement of the building itself due to soil consolidation. In deep foundation pit projects, the depth of the pit inevitably crosses multiple aquifers. Therefore, the water extracted by this device can be stored in a surface reservoir or in a deeper aquifer. When the groundwater level drops, it can be replenished to different aquifers through pumping / recharge wells, preventing uneven settlement of the surface caused by soil consolidation around the building. The extracted water can also be used for urban greening and other purposes. This system maintains the pressure balance between the soil and the building foundation while conserving water resources, making it green, energy-saving, and environmentally friendly.

[0067] The present invention provides a pre-embedded self-balancing water pressure method for building foundation slabs to prevent buoyancy and sinking throughout the building's lifecycle. By placing the outlet of the water supply pipe 4 at a designated aquifer, water can be replenished to different aquifers. Taking the dewatering operation of a newly constructed foundation pit around the main building as an example, the drop in groundwater level will inevitably cause the surrounding foundation soil to lose water and consolidate, which may lead to differential settlement of the building. In this case, by rationally deploying a deep well recharge system, the groundwater seepage field can be actively regulated, forming a water level control barrier between the dewatering-affected area and the building foundation, thereby effectively controlling stratum deformation and suppressing the development of uneven settlement of the building structure.

[0068] The pumping / recharge system of this invention can perform pumping or recharge operations on single or multiple aquifers. By changing the pumping direction, dewatering of the foundation pit can be achieved, and it also supports single-layer or multi-layer combined operation.

[0069] When the water level of the aquifer drops due to the dewatering of the new foundation pit around the building, which may cause uneven settlement of the building, the water in the underground aquifer will be pumped out and recharged to the building's strata to reduce strata deformation and uneven settlement.

[0070] The system supports flexible pumping or recharge operations for multiple settlement control units and single or multiple aquifers, effectively controlling stratum deformation and suppressing uneven settlement of building structures.

[0071] This invention can be used in the following scenarios depending on actual working conditions:

[0072] like Figure 5As shown in Scenario 1 (Building Structure Operation and Maintenance Phase): When the groundwater level rises, water is pumped out through the settlement control unit 6 and the pumping equipment and injected into the aquifer at the bottom of the weakly permeable layer below the building structure to prevent the pore water pressure from increasing and causing excessive buoyancy of the building slab, resulting in shear failure; when the groundwater level drops, water is reinjected from the aquifer at the bottom of the weakly permeable layer into the soil layer to maintain the effective stress balance of the soil and prevent differential settlement of the building caused by soil water loss, consolidation and collapse.

[0073] like Figure 6 As shown in Scenario 2 (new foundation pit): When the dewatering of a new foundation pit around a building causes the water level of the surrounding aquifer to drop, which may lead to uneven settlement of the existing building or affect the surrounding soil environment, the water in the aquifer at the bottom of the underground weak permeable layer can be pumped out to recharge the existing building, thereby reducing ground deformation and uneven settlement.

[0074] like Figure 3 As shown in Scenario 3: The system supports independent pumping or recharge operations for multiple settlement control units 6 when facing ultra-large irregular foundation pits.

[0075] Scenario 4: It can flexibly carry out pumping or recharge operations for single or multiple aquifers, and can specifically control stratum deformation and suppress uneven settlement of building structures by regulating the water level of the aquifer.

[0076] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for self-balancing water pressure in a pre-embedded foundation slab for anti-buoyancy and anti-sinking throughout the building's lifecycle, characterized in that, Includes the following steps: Install pumping equipment and ground water storage tanks, so that at least two pipelines in the pumping equipment are respectively connected to the two aquifers at the bottom of the foundation pit, and the two aquifers are separated by at least one weakly permeable layer. Real-time monitoring of the soil pressure status of the uppermost aquifer at the bottom of the foundation pit; The rise and fall of the groundwater level is determined by the monitored pressure value. When the monitored pressure value is abnormal, the groundwater in the uppermost aquifer is pumped or recharged: when the pressure value exceeds the set threshold, the groundwater level rises and the groundwater in the aquifer at the bottom of the foundation pit is pumped; when the pressure value is lower than the set threshold, the groundwater level falls and the groundwater in the aquifer at the bottom of the foundation pit is recharged.

2. The pre-embedded base slab water pressure self-balancing method for building life-cycle anti-buoyancy and anti-sinking as described in claim 1, characterized in that, When the groundwater in the aquifer at the bottom of the foundation pit is pumped out, the pumped water is discharged to a surface reservoir and / or an aquifer below the weakly permeable layer; when the groundwater in the aquifer at the bottom of the foundation pit is recharged, the recharged water source comes from the pumped water stored in the surface reservoir and / or from the aquifer below the weakly permeable layer.

3. A pre-embedded system for building anti-buoyancy and anti-sinking, used to implement the pre-embedded base slab water pressure self-balancing method for building full-cycle anti-buoyancy and anti-sinking as described in any one of claims 1-2, characterized in that, Includes the retaining structure (5) set in the inner wall of the foundation pit, and the foundation slab is poured at the bottom of the foundation pit; Also includes: A frame support structure is set inside the foundation pit. The edge of the frame support structure contacts the inner wall of the retaining structure (5) to provide support. The bottom of the frame support structure extends to the bottom of the foundation slab, and the frame support structure is hollow to form a channel for groundwater flow. A pumping device, wherein the pumping device is connected to the frame support structure; A surface water storage tank, which is connected to the pumping equipment; The frame support structure includes multiple settlement control units (6), adjacent settlement control units (6) are fixedly connected, and the side wall of the settlement control unit (6) located at the edge is in contact with the inner wall of the enclosure structure (5).

4. The pre-embedded anti-buoyancy and anti-sinking system for buildings according to claim 3, characterized in that, The settlement control unit (6) includes a three-dimensional frame structure composed of several hollow beams (3); several hollow beams (3) located at the bottom of the three-dimensional frame structure are set below the foundation plate and in contact with the soil layer at the bottom of the pit; several seepage pipes (2) are connected between a pair of parallel hollow beams (3) located at the bottom, and a filter layer (7) is set at the bottom of the seepage pipes (2), and the seepage pipes (2) are connected to the soil layer at the bottom of the pit through the filter layer (7); a water conveying pipe (4) is set inside the vertically set hollow beams (3), and the water conveying pipe (4) is connected to the pumping equipment.

5. The pre-embedded system for preventing buoyancy and sinking in buildings according to claim 4, characterized in that, A pressure detection unit is provided between the soil surface at the bottom of the foundation pit and the hollow beam (3) located at the bottom.

6. The pre-embedded system for preventing buoyancy and sinking in buildings according to claim 5, characterized in that, The pressure detection unit includes several pressure sensors (1) that are evenly arranged.

7. The pre-embedded system for preventing buoyancy and sinking in buildings according to claim 4, characterized in that, The filter layer (7) includes a metal filter screen and a geotextile arranged sequentially from top to bottom.

8. The pre-embedded system for preventing buoyancy and sinking in buildings according to claim 3, characterized in that, The retaining structure (5) is an engineering pile and / or a diaphragm wall.

9. The pre-embedded system for preventing buoyancy and sinking in buildings according to claim 4, characterized in that, The pumping equipment includes a pumping station, which is connected to the hollow beam column (3) through the water supply pipe (4) and is also connected to the ground water storage tank. The pumping equipment also includes a deep well, and the pumping station is connected to the aquifer below the foundation slab through pipelines in the deep well.

10. The pre-embedded system for preventing buoyancy and sinking in buildings according to claim 9, characterized in that, Solenoid valves are installed at both the inlet and outlet of the pump station.

Images