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CN-121976553-A - Intelligent efficient vacuum dewatering system and foundation pit construction process using same

CN121976553ACN 121976553 ACN121976553 ACN 121976553ACN-121976553-A

Abstract

The application discloses an intelligent high-efficiency vacuum dewatering system and a foundation pit construction process using the same, and in particular relates to the technical field of foundation pit dewatering, comprising a vacuum dewatering well, wherein a well pipe is embedded in the middle of the vacuum dewatering well, through holes are formed in the surface of the well pipe, multiple groups of through holes are arranged at equal intervals, a sealing cover is arranged at the top of the well pipe, a vacuum suction mechanism is arranged in the middle of the well pipe, the vacuum suction mechanism comprises an air compressor, an air supply pipe, a water suction pipe and a vacuum water suction pump, one side of the vacuum dewatering well is provided with the air compressor, and the end part of the air compressor is fixedly connected with the air supply pipe; according to the application, the negative pressure value in the well pipe is monitored in real time through the pressure sensor arranged on the inner wall of the well pipe, key data is provided for system running state evaluation and intelligent control, the double sealing ring and the sealing gasket effectively reduce air leakage, ensure vacuum effect and improve precipitation stability.

Inventors

  • ZHU RUI
  • HUANG GUOPENG
  • CHEN PEIJI
  • ZHOU XIONG
  • ZHANG MAOPENG
  • ZHOU YIBING
  • CHEN CHEN
  • HE DUOWEI
  • NIE QIANG
  • CAO SHENGLI
  • ZHOU SHENG
  • GONG JIWEI

Assignees

  • 中铁广州工程局集团有限公司
  • 中铁广州工程局集团第三工程有限公司

Dates

Publication Date
20260505
Application Date
20251230

Claims (10)

  1. 1. The intelligent efficient vacuum dewatering system comprises a vacuum dewatering well (1) and is characterized in that a well pipe (2) is embedded in the middle of the vacuum dewatering well (1), through holes (3) are formed in the surface of the well pipe (2), multiple groups of the through holes (3) are arranged at equal intervals, a sealing cover (4) is arranged at the top of the well pipe (2), a vacuum suction mechanism (5) is arranged in the middle of the well pipe (2), the vacuum suction mechanism (5) comprises an air compressor (6), an air supply pipe (7), a water suction pipe (8) and a vacuum water suction pump (9), one side of the vacuum dewatering well (1) is provided with the air compressor (6), the end part of the air compressor (6) is fixedly connected with the air supply pipe (7), the end part of the air supply pipe (7) penetrates through the sealing cover (4) and extends into the well pipe (2), one side of the air compressor (6) is provided with the vacuum water suction pump (9), and the water suction end of the vacuum water pump (9) is fixedly connected with the water suction pipe (8).
  2. 2. The intelligent efficient vacuum dewatering system according to claim 1, wherein the bottom end of the water suction pipe (8) penetrates through the sealing cover (4) to extend to the inner bottom end of the well pipe (2), sealing rings (10) are arranged at the joints of the air supply pipe (7) and the water suction pipe (8) and the sealing cover (4), a filter screen (11) is fixedly connected to the end part of the water suction pipe (8), a sealing gasket (12) is arranged on one side of the bottom of the edge of the sealing cover (4), and a pressure sensor (13) is fixedly connected to one side of the inner wall of the well pipe (2).
  3. 3. The intelligent efficient vacuum dewatering system according to claim 2, wherein a reinforcing sealing mechanism (14) is arranged at the bottom of the sealing cover (4), the reinforcing sealing mechanism (14) comprises a movable cavity (15), a rotating shaft (16), a first bevel gear (17), a limiting cavity (18), a threaded cylinder (19), a second bevel gear (20), a screw rod (21), a sealing cylinder (22), a rubber air bag ring (23) and a piston (24), the movable cavity (15) is arranged on the inner wall of the middle of the sealing cover (4), and the inner wall of the top of the movable cavity (15) is connected with the rotating shaft (16) through a bearing.
  4. 4. The intelligent efficient vacuum dewatering system according to claim 3, wherein a first bevel gear (17) is connected to the outer wall of the bottom of the rotating shaft (16), a limiting cavity (18) is communicated with the edge of the movable cavity (15), multiple groups of limiting cavities (18) are arranged, a threaded cylinder (19) is connected to the inner wall of the middle of each limiting cavity (18) through a bearing, one end of each threaded cylinder (19) extends into the movable cavity (15), a second bevel gear (20) is fixedly connected to the end of each threaded cylinder (19), and the first bevel gear (17) is meshed with the second bevel gear (20).
  5. 5. The intelligent efficient vacuum dewatering system according to claim 4, wherein a screw rod (21) is connected to the inner wall of one end of the threaded cylinder (19) far away from the secondary bevel gear (20) in a threaded mode, a sealing cylinder (22) is arranged at the edge of the sealing cover (4), the sealing cylinder (22) is communicated with the limiting cavity (18), a rubber air bag ring (23) is fixedly connected to the edge of the sealing cover (4), a piston (24) is connected to the inner wall of the middle of the sealing cylinder (22) in a sliding mode, and one end of the screw rod (21) far away from the threaded cylinder (19) extends into the sealing cylinder (22) to be fixedly connected with the piston (24).
  6. 6. The intelligent efficient vacuum dewatering system according to claim 5, wherein the inner wall of the top of the well pipe (2) is provided with a mounting groove (25), the mounting groove (25) is provided with a plurality of groups, one side of the bottom end of the limiting cavity (18) is provided with a bar-shaped groove (26), the middle part of the bar-shaped groove (26) is connected with a connecting block (27) in a sliding manner, the top end of the connecting block (27) is fixedly connected with a screw rod (21), the bottom end of the connecting block (27) passes through the bar-shaped groove (26) to be connected with a push rod (28), the end part of the push rod (28) is fixedly connected with a mounting positioning block (29), the mounting positioning block (29) is matched with the mounting groove (25), the center of the top of the sealing cover (4) is provided with a locking hand wheel (30), and the adjusting end of the locking hand wheel (30) is fixedly connected with a rotating shaft (16).
  7. 7. The foundation pit construction process using the intelligent high-efficiency vacuum dewatering system is characterized in that the foundation pit construction process using the intelligent high-efficiency vacuum dewatering system as claimed in any one of claims 1 to 6: Firstly, construction preparation, namely determining the well spacing, well depth and precipitation depth targets of a plane arrangement well of a vacuum precipitation well (1) based on foundation pit excavation depth, geological hydrologic conditions and supporting design schemes, constructing the vacuum precipitation well (1) outside a foundation pit excavation outline, installing a well pipe (2), a sealing cover (4) and a vacuum suction mechanism (5), completing connection of an air supply pipe (7), a water suction pipe (8) with an air compressor (6) and a vacuum water suction pump (9), calibrating a pressure sensor (13), and connecting the pressure sensor to an automatic monitoring system; The method comprises the steps of pre-dewatering before excavation and dynamic regulation, arranging an annular drainage ditch around a foundation pit, starting a vacuum suction mechanism (5) to pre-dewatering before each layer of earth excavation of the foundation pit, conveying compressed air into a well pipe (2) through an air supply pipe (7) by an air compressor (6), forming a negative pressure environment in the well, enabling groundwater to be accelerated and converged into the well under the action of negative pressure through a through hole (3) on the surface of the well pipe (2), discharging the groundwater into the drainage ditch outside the foundation pit through a vacuum suction pump (9) and a suction pipe (8), discharging the groundwater into municipal pipelines, reading data of a pressure sensor (13) in real time in the process, dynamically adjusting operation parameters of the air compressor (6) and the vacuum suction pump (9) through the automatic monitoring system, and ensuring that the groundwater level is not less than 1.0 meter below a current planned excavation surface, and the water level deep-down rate accords with a preset safety threshold; Excavating a foundation pit, namely firstly excavating to the elevation of the working surface of a supporting pile, completing crown beam and inner support construction and reaching the design strength, then excavating a large area of earth and stone, wherein the earth and stone excavation is conducted according to the principles of layering, segmentation and symmetry, the continuous operation of a vacuum dewatering system is kept during excavation, a dewatering strategy is adjusted in real time according to the condition of the stratum exposed during excavation, feedback information of a pressure sensor (13) and monitoring data of the surrounding environment of the foundation pit, the layer height difference during excavation is less than 1.5m, and the soil mass in 20cm around the foundation pit is manually cleaned and repaired to avoid damaging a supporting structure; Step four, foundation pit support, namely excavating earthwork to the bottom of an inner support beam after foundation pit support piles and engineering pile foundations are constructed, carrying out support and crown beam construction, carrying out trestle construction at the same time, and excavating residual earthwork after the inner support strength reaches the design strength; And fifthly, maintaining a dewatering system, periodically checking the tightness of the sealing cover (4) in the whole construction period of the foundation pit, driving the reinforcing sealing mechanism (14) to enhance the sealing effect by operating the locking hand wheel (30) if necessary, monitoring the working state of the filter screen (11), preventing blockage, gradually reducing the dewatering strength after the basement structure construction is completed, monitoring the rising condition of the groundwater level after the anti-floating capacity is achieved and dewatering is not needed any more, stopping dewatering after confirming that the structure is not influenced, and sealing the vacuum dewatering well (1) according to the specifications.
  8. 8. The foundation pit construction process using the intelligent efficient vacuum dewatering system according to claim 7, wherein in the first step, a three-dimensional groundwater seepage model is built by using geological investigation data, the arrangement scheme of the vacuum dewatering well (1) is optimized through numerical simulation, ground subsidence caused by dewatering is predicted, and a subsidence control standard of a key protection object is set, wherein the standard is used as one of the basis of dynamic regulation.
  9. 9. The foundation pit construction process using the intelligent efficient vacuum dewatering system according to claim 7, wherein in the second step, the dynamic regulation is specifically that an automatic monitoring system presets a water level lowering rate alarm value, when the pressure sensor (13) monitors that the negative pressure value in the well pipe (2) abnormally fluctuates or the water level lowering rate exceeds the alarm value, the system automatically alarms and prompts to check the sealing performance of the sealing ring (10), the rubber air bag ring (23) or the blocking condition of the filter screen (11), and simultaneously, the air supply pressure of the air compressor (6) or the suction flow of the vacuum suction pump (9) is automatically regulated, so that the stable dewatering efficiency is maintained.
  10. 10. The foundation pit construction process using the intelligent efficient vacuum dewatering system according to claim 7, wherein in the third step, zonal differential dewatering is implemented according to the unearthing sequence and the supporting construction progress of different areas in the foundation pit, for the area which is being excavated or is to be constructed and supported, the dewatering strength of the vacuum dewatering wells (1) around the area is increased in advance, and for the area which is completed with support and stable deformation, the dewatering strength of the peripheral well points is reduced appropriately on the premise of meeting the water level control requirement.

Description

Intelligent efficient vacuum dewatering system and foundation pit construction process using same Technical Field The application relates to the technical field of foundation pit dewatering, in particular to an intelligent high-efficiency vacuum dewatering system and a foundation pit construction process using the same. Background Before the foundation pit is excavated, the groundwater level of a preset place of the foundation pit needs to be measured. When the groundwater level in the soil layer is higher than the height of the bottom of the foundation pit preset by the foundation pit to be excavated, accidents such as groundwater leakage or soil loosening are easily caused in the excavation process, and the groundwater level needs to be reduced. The foundation pit dewatering system is used for reducing the height of the groundwater level in the soil layer of the foundation pit to be excavated, and has wide application; According to the prior patent publication No. CN105064384B, a vacuum pipe well dewatering system is disclosed, pipe wells which are arranged in a display shape are drilled at the same interval along the longitudinal direction under the soil of a foundation pit, a well point pipe is inserted into each pipe well, water absorbing holes are distributed along the outer wall of the well point pipe, a filter material layer with strong water permeability is filled between the inner wall of the pipe well and the outer wall of the well point pipe, a clay layer with a certain thickness is filled above the filter material layer in the pipe well, a grid-shaped water collecting main pipe which is formed by intersecting transverse pipes and longitudinal pipes and communicated with each other is buried in the clay layer, the positions of the pipe wells are arranged below the grid-shaped intersection of the water collecting main pipe, the ends of each transverse pipe and each longitudinal pipe are communicated with the well point pipe in the pipe well, a layer of concrete layer is paved on the upper surface of the foundation pit, the pipe opening of the well point pipe is exposed outside the concrete layer, and the water collecting main pipe is communicated with the water collecting main pipe through a centrifugal pump and a vacuum pump respectively. The application ensures the tightness and strength of the soil of the foundation and provides reliable guarantee for the safety of subsequent construction. The inventors found that the following problems exist in the prior art in the process of implementing the present application: The traditional dewatering method is suitable for the conditions of shallow foundation pits and good stratum permeability by draining water through open trenches and dewatering water through water collecting wells, the dewatering depth is limited by collecting water flows under the action of gravity, soil loss around the foundation pits is easy to occur, the ground is caused to sink in weak permeable layers such as fine sand and silt, dewatering efficiency is extremely low, effective dewatering is almost impossible, and light well point dewatering is realized, or a certain vacuum degree is formed in a well point pipe through a vacuum pump, underground water is accelerated to be collected to well points, but only one group of sealing structures are arranged between a vacuum well and a sealing cover, and the dewatering effect is easy to be affected due to large sealing leakage of internal and external pressure differences in the vacuum dewatering process; therefore, an intelligent high-efficiency vacuum dewatering system and a foundation pit construction process using the same are provided for solving the problems. Disclosure of Invention In order to overcome the defects in the prior art, the application provides an intelligent high-efficiency vacuum dewatering system and a foundation pit construction process using the dewatering system, so as to solve the problems in the background art. In order to achieve the purpose, the intelligent efficient vacuum dewatering system comprises a vacuum dewatering well, wherein a well pipe is embedded in the middle of the vacuum dewatering well, through holes are formed in the surface of the well pipe, multiple groups of the through holes are arranged at equal intervals, a sealing cover is arranged at the top of the well pipe, a vacuum suction mechanism is arranged in the middle of the well pipe and comprises an air compressor, an air supply pipe, a water suction pipe and a vacuum water suction pump, one side of the vacuum dewatering well is provided with the air compressor, the end part of the air compressor is fixedly connected with the air supply pipe, the end part of the air supply pipe penetrates through the sealing cover and extends into the well pipe, a vacuum water suction pump is arranged on one side of the air compressor, and the water suction end of the vacuum water suction pump is fixedly connected with the water suction pipe. Preferably,