Method for reducing settlement of peripheral soil body resisted by peripheral pipe piles of basement

Abstract

The invention discloses a method for reducing basement peripheral pipe piles to resist peripheral soil settlement, and relates to the technical field of buildings, and the method comprises a peripheral soil settlement reducing and resisting mechanism and waste pipe piles; the mechanism for reducing and resisting surrounding soil settlement is composed of a prefabricated concrete pipe, a prefabricated reinforced concrete plate and foundation sand. The ground is recovered by finding piles, filling sand, pressing in the prefabricated concrete pipe, backfilling earthwork to stabilize the prefabricated concrete pipe, plastering, covering the prefabricated concrete pipe with the prefabricated reinforced concrete plate and finally backfilling the earthwork to the ground surface; a mechanism for reducing and resisting surrounding soil settlement is arranged, so that the settlement speed of the ground above the waste pipe pile can be effectively controlled, the settlement speed of the ground above the waste pipe pile is kept consistent with that of the surrounding ground, and ground cracking caused by settlement difference is avoided; the problem that the ground of municipal and garden supporting facilities is prone to damage due to the fact that the settling velocity of the ground above foundation pipe piles of waste tower cranes, people and goods elevators and other structures is inconsistent with that of the surrounding ground is solved.

Description

Technical Field

[0001] The invention relates to the technical field of construction, and in particular to a method for reducing the peripheral pipe piles of a basement to resist the settlement of surrounding soil. Background Art

[0002] In most current construction projects, before the main building is built, it is necessary to lay pipe piles outside the main building foundation to support the building crane, and then pour the crane foundation on the pipe piles. After the main building begins the main stacking construction, the crane is installed on the crane foundation. After the main building is completed, the crane will be dismantled and the pipe pile foundation will be abandoned on the open space. After the main building is completed, the surrounding open space will be built into gardens, green belts, sidewalks or squares, and the abandoned tower crane pipe pile foundations that have not been dismantled will also be buried under the concrete ground base of the constructed gardens, green belts, sidewalks or squares.

[0003] With the rain, periodic pressure of the ground and soil movement, the construction of garden ground, square ground, pedestrian road or driving road will sink. The reasons for the sinking can be understood from two aspects: natural factors and human factors:

[0004] (1) Natural factors mainly include natural disasters such as earthquakes, landslides, collapses, and ground movement caused by crustal movement. Crustal movement can cause some places to rise while other places to fall, and the decomposition of organic matter in the soil can also cause the ground to compress.

[0005] (2) Human factors mainly include excessive groundwater extraction, mining of solid minerals, and exploitation of oil and natural gas, which can cause land subsidence. In addition, human engineering and economic activities such as slope excavation, landfilling, and improper construction such as piling and concrete pouring without taking effective technical measures can also cause land subsidence.

[0006] However, due to the presence of abandoned tower crane pipe piles in some areas and the high bearing capacity of the pipe pile foundations, the settlement rate of the earth above the pipe pile foundations is very slow. The settlement rate of the ground above the pipe pile foundations is inconsistent with the settlement rate of the surrounding ground, resulting in uneven ground, cracks or collapse.

[0007] The usual practice in the garden construction industry is to replace the earth on the top of the pipe pile foundation, blast away and remove a certain length of pipe piles, or directly backfill the earth on the abandoned pipe pile foundation without processing. According to the follow-up records of the later stage of garden construction, such solutions will cause the earth, roads, pipelines and other structures, equipment and facilities in the area above the top of the pipe piles to be arched and damaged when the ground settles as a whole, because they do not settle synchronously with the surrounding ground, and eventually become unable to be used normally.

[0008] Therefore, for the municipal and garden supporting facilities around the building, it is particularly important to prevent the later settlement rate of the tower crane pipe pile foundation from being inconsistent with the settlement rate of the surrounding ground, which will affect the normal use of the surrounding ground.

[0009] In summary, it is found that the prior art has at least the following technical problems:

[0010] The ground settlement rate above the foundation piles of abandoned tower cranes, passenger and freight elevators, and other structures is inconsistent with the surrounding ground, which leads to the problem that the ground of municipal and garden supporting facilities is easily damaged. Summary of the invention

[0011] The purpose of the present invention is to provide a method for reducing the surrounding soil settlement of the outer pipe piles of the basement, so as to solve the problem that the ground settlement speed above the foundation pipe piles of abandoned tower cranes, passenger and freight elevators, and other structures is inconsistent with the surrounding ground, resulting in easy damage to the ground of municipal and garden supporting facilities.

[0012] The various technical effects that can be produced by the preferred technical solutions among the various technical solutions provided by the present invention are described in detail below.

[0013] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0014] The present invention provides a method for reducing the settlement of surrounding soil by using pipe piles outside a basement, comprising a mechanism for reducing the settlement of surrounding soil for controlling the settlement speed of earth and ground above the abandoned pipe piles and abandoned pipe piles below the ground settlement speed to be controlled; the mechanism for reducing the settlement of surrounding soil consists of precast concrete pipes, precast reinforced concrete slabs and foundation sand;

[0015] The construction steps include:

[0016] S1: Find the location of the abandoned pipe pile foundation, excavate the ground surface, and excavate to a depth of 3 meters below the top surface of the abandoned pipe pile, and the diameter of the excavation area is 4 times the diameter of the abandoned pipe pile;

[0017] S2: leveling the bottom of the excavation area;

[0018] S3: Filling the foundation sand into the excavation area until the foundation sand is flush with the top surface of the abandoned pipe pile;

[0019] S4: lowering the precast concrete pipe to the excavation area, so that the precast concrete pipe is sleeved outside the abandoned pipe pile, and the abandoned pipe pile is located in the center area of ​​the precast concrete pipe; the length of the lower precast concrete pipe is 2.5-3 meters;

[0020] S5: Pressing the precast concrete pipe into the foundation sand to a depth of one fifth of the length of the precast concrete pipe, so that there is foundation sand between the precast concrete pipe and the abandoned pipe pile, and a cavity is left between the top end surface of the precast concrete pipe and the top end surface of the abandoned pipe pile;

[0021] S6: Stabilize the precast concrete pipe, and backfill earth between the precast concrete pipe and the excavation area until the earth is flush with the top surface of the precast concrete pipe;

[0022] S7: applying a layer of cement mortar to the top surface of the precast concrete pipe;

[0023] S8: Covering the precast reinforced concrete slab on the top surface of the precast concrete pipe, the area of ​​the precast reinforced concrete slab is larger than the cross-sectional area of ​​the precast concrete pipe;

[0024] S9: backfilling soil onto the prefabricated reinforced concrete slab to the ground surface and compacting it;

[0025] The cavity left between the top end surface of the precast concrete pipe and the top end surface of the abandoned pipe pile is used to reserve space for ground settlement, so that the ground settlement speed above the abandoned pipe pile is consistent with the settlement speed of the surrounding ground.

[0026] In one of the embodiments, it also includes a plurality of satellite traction mechanisms, the satellite traction mechanisms include a pile core, a pressure plate, a collar and a first pull rope; the outer wall surface of the collar and the lower end surface of the precast reinforced concrete slab are provided with connecting ear plates; in step S1, an excavation area of ​​12-15 times the area of ​​the precast reinforced concrete slab is excavated 8 meters away from the excavation area to a satellite area 6.5 meters below the top surface of the abandoned pipe pile; the pile core with a length of at least 4 meters is inserted at least 1 meter below the bottom end of the satellite area with the conical end of the pile core; the collar is put on the outside of the pile core so that the collar falls on the bottom end of the satellite area, and the ear plate of the collar is rotated to the ear plate opposite to the precast reinforced concrete slab; a first trench is excavated along the straight path from the ear plate of the collar to the ear plate of the precast reinforced concrete slab. groove, the depth of the first groove corresponds to the depth of the satellite area; placing the first pull rope in the first groove, so that the two ends of the first pull rope are respectively connected and fixed to the ear plate of the ring and the ear plate of the precast reinforced concrete slab; backfilling earth into the satellite area and the first groove to the top surface of the pile core; placing the pressure plate on the top surface of the pile core, and connecting and fixing the pile core to the pressure plate; backfilling earth onto the pressure plate and the first groove to the surface and compacting it; after the settlement space reserved in the precast concrete pipe is compressed, the satellite traction mechanism bears the earth pressure above it by means of the pressure plate, and multiple satellite traction mechanisms are combined and apply downward pulling force to the abandoned pipe pile through their respective rings and the first pull rope, and the abandoned pipe pile gradually sinks under the pulling force.

[0027] In one of the embodiments, the first tension rope connects the ear plate of the ring and the ear plate of the prefabricated reinforced concrete slab in a pre-tensioned manner.

[0028] In one of the embodiments, at least eight satellite traction mechanisms are provided and are evenly arranged around the axis of the mechanism for reducing and resisting surrounding soil settlement.

[0029] In one of the embodiments, a second groove is excavated between adjacent satellite areas, a second pull rope is placed in the second groove, and two ends of the second pull rope are connected to the ear plates of two adjacent rings in a pre-tensioned manner.

[0030] In one of the embodiments, wing plates are provided on two adjacent surfaces of the pressure plate, and the two wing plates are arranged toward the mechanism for reducing and resisting settlement of surrounding soil; the wing plates are used to prevent the pile core and the pressure plate from tilting inward toward the mechanism for reducing and resisting settlement of surrounding soil when the ring applies tension to the first pull rope.

[0031] In one of the embodiments, the pile core, the pressure plate and the wing plate are all precast concrete components, wherein the pressure plate and the wing plate are cast as one piece; a threaded rod is provided at the axis of the pile core, and a connecting through hole is provided at the center of the pressure plate; when the pile core and the pressure plate are assembled, the threaded rod is passed through the connecting through hole, and the pile core and the pressure plate are locked by a nut.

[0032] In one of the embodiments, the multiple satellite traction mechanisms arranged around a single abandoned pipe pile form a pipe pile sinking group; a third pull rope is also included, each adjacent abandoned pipe pile is respectively arranged with a group of the pipe pile sinking groups, and the multiple pipe pile sinking groups are connected by the third pull rope; the two ends of the third pull rope are respectively connected to the ear plates of the adjacent rings.

[0033] In one embodiment, the area of ​​the pressure plate is 12-15 times the area of ​​the prefabricated reinforced concrete slab.

[0034] In one embodiment, the prefabricated reinforced concrete slab has a thickness of at least 150 mm and is cast using concrete with a grade of at least C35.

[0035] The beneficial effects of the present invention are as follows:

[0036] First, by setting up a mechanism to reduce the settlement of the surrounding soil above the abandoned pipe piles, the settlement rate of the ground above the abandoned pipe piles is effectively controlled, so that the settlement rate of the ground above the abandoned pipe piles is consistent with that of the surrounding ground; in the first synchronous ground settlement stage, the damage to the municipal and garden supporting facilities caused by the settlement difference is avoided. This synchronous ground settlement design in different areas significantly improves the stability and safety of the municipal and garden supporting facilities and the ground.

[0037] Secondly, the present invention uses precast concrete pipes and foundation sand to form a buffer structure, wherein the foundation sand is used as a filling material and has good compression resistance and uniform settlement performance. By filling the foundation sand between the precast concrete pipes and the abandoned pipe piles, the direct effect of the ground pressure on the abandoned pipe piles is further alleviated, reducing the risk of uneven ground settlement.

[0038] Thirdly, by using precast concrete pipes and precast reinforced concrete slabs in construction, the efficiency of the construction process and the standardization of materials are ensured. This prefabricated component reduces the complexity of on-site processing, shortens the construction period, and improves the construction quality and reliability. And the precast concrete pipes can be replaced by concrete drainage pipes because the materials can be obtained locally; in addition, the concrete material has a long service life, which enhances the durability of the entire structure.

[0039] During the construction process, there are multiple layers of protection measures. Cement mortar is applied to the top of the precast concrete pipe and covered with a precast reinforced concrete slab to prevent the soil from being squeezed into the gap between the precast concrete pipe and the precast reinforced concrete slab under the pressure of the ground, thereby preventing erosion and reducing the cavity reserved for ground settlement on the inner wall of the precast concrete pipe, further increasing the time for the ground above the abandoned pipe piles to settle synchronously with the surrounding ground. By backfilling soil to the surface and compacting it on the precast reinforced concrete slab, not only the soil layer on the surface of the ground is restored, but also the flatness and stability of the surface are ensured, avoiding ground depression or collapse caused by uneven settlement.

[0040] Finally, a cavity is reserved between the top surface of the precast concrete pipe and the top surface of the abandoned pipe pile to provide a buffer space for ground settlement, avoiding excessive pressure accumulation of concrete stress on the ground above the abandoned pipe pile due to insufficient settlement, thereby effectively improving the integrity of the concrete on the ground above the abandoned pipe pile, thereby avoiding ground cracking. This design concept is highly adaptable and is particularly suitable for foundation treatment under complex geological conditions outside the basement.

[0041] In summary, the present invention significantly improves the settlement integrity, safety and uniformity of the ground above and around abandoned pipe piles, effectively reduces the impact of abandoned pipe piles on municipal and garden supporting facilities, and has wide engineering application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0043] Figure 1 It is a schematic cross-sectional view of the structure of the mechanism for reducing and resisting the settlement of surrounding soil in the first embodiment of the present invention;

[0044] Figure 2 1 is a schematic diagram of a top view of a circular prefabricated reinforced concrete slab according to a first embodiment of the present invention;

[0045] Figure 3 1 is a schematic diagram of a top view of a square prefabricated reinforced concrete slab according to a first embodiment of the present invention;

[0046] Figure 4 It is a cross-sectional structural schematic diagram of a mechanism for reducing and resisting surrounding soil settlement and a satellite traction mechanism according to a second embodiment of the present invention;

[0047] Figure 5 It is a schematic diagram of a top view of the structure of a mechanism for reducing and resisting the settlement of surrounding soil and a satellite traction mechanism according to a second embodiment of the present invention;

[0048] Figure 6 It is a schematic diagram of the top view of the structure of multiple pipe pile sinking groups according to the third embodiment of the present invention.

[0049] The reference numerals are as follows:

[0050] 1. Mechanism for reducing and resisting the settlement of surrounding soil; 11. Prefabricated concrete pipe; 12. Prefabricated reinforced concrete slab; 13. Foundation sand;

[0051] 2. Excavation area; 21. Earthwork;

[0052] 3. Satellite traction mechanism; 31. Pile core; 32. Pressure plate; 321. Wing plate; 33. Ring; 34. First pull rope; 35. Ear plate;

[0053] 4. Second pull rope;

[0054] 5. Pipe pile sinking group; 51. Third pull rope;

[0055] 6. Abandoned pipe piles;

[0056] 7. Ground. DETAILED DESCRIPTION

[0057] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0058] A specific implementation method is provided for reducing the settlement of surrounding soil by pipe piles on the periphery of a basement, including a mechanism for reducing the settlement of surrounding soil and abandoned pipe piles; the mechanism for reducing the settlement of surrounding soil is composed of precast concrete pipes, precast reinforced concrete slabs and foundation sand; the ground is restored by finding piles, filling sand, pressing into precast concrete pipes, backfilling earth to stabilize the precast concrete pipes, applying slurry, covering the precast concrete pipes with precast reinforced concrete slabs and finally backfilling earth to the surface; a mechanism for reducing the settlement of surrounding soil is provided, which can effectively control the settlement speed of the ground above the abandoned pipe piles, so that the settlement speed of the ground above the abandoned pipe piles is consistent with that of the surrounding ground, avoiding ground cracking due to settlement differences; it effectively solves the problem that the settlement speed of the ground above the foundation pipe piles of abandoned tower cranes, passenger and freight elevators and other structures is inconsistent with the surrounding ground, resulting in easy damage to the ground of municipal and garden supporting facilities.

[0059] In addition, all the contents of the configurations shown in the following embodiments are not necessarily limited to the solutions of the invention described in the claims.

[0060] The first implementation of the method of reducing the surrounding soil settlement by pipe piles outside the basement Figures 1 to 3As shown, it includes a mechanism 1 for reducing and resisting the settlement of surrounding soil for controlling the settlement rate of earth 21 and ground 7 above the abandoned pipe piles 6, and the abandoned pipe piles 6 below the settlement rate of the ground 7 to be controlled; the mechanism 1 for reducing and resisting the settlement of surrounding soil is composed of a precast concrete pipe 11, a precast reinforced concrete slab 12 and foundation sand 13.

[0061] The construction steps include:

[0062] S1: Find the foundation position of the abandoned pipe pile 6, excavate the surface, and excavate to a depth of 3 meters below the top surface of the abandoned pipe pile 6, and the diameter of the excavation area 2 is 4 times the diameter of the abandoned pipe pile 6;

[0063] S2: leveling the bottom of excavation area 2;

[0064] S3: Fill the excavation area 2 with foundation sand 13, so that the foundation sand 13 is flush with the top surface of the abandoned pipe pile 6;

[0065] S4: lowering the precast concrete pipe 11 to the excavation area 2, so that the precast concrete pipe 11 is sleeved outside the abandoned pipe pile 6, and the abandoned pipe pile 6 is located in the center area of ​​the precast concrete pipe 11; the length of the lower precast concrete pipe 11 is 2.5-3 meters;

[0066] S5: Press the precast concrete pipe 11 into the foundation sand 13 to a depth of one fifth of the length of the precast concrete pipe 11, so that there is foundation sand 13 between the precast concrete pipe 11 and the abandoned pipe pile 6, and a cavity is left between the top surface of the precast concrete pipe 11 and the top surface of the abandoned pipe pile 6;

[0067] S6: Stabilize the precast concrete pipe 11, and backfill the earth 21 between the precast concrete pipe 11 and the excavation area 2 until it is flush with the top surface of the precast concrete pipe 11;

[0068] S7: Apply a layer of cement mortar to the top surface of the precast concrete pipe 11;

[0069] S8: Cover the top surface of the precast concrete pipe 11 with a precast reinforced concrete slab 12, wherein the area of ​​the precast reinforced concrete slab 12 is larger than the cross-sectional area of ​​the precast concrete pipe 11;

[0070] S9: backfilling earth 21 onto the prefabricated reinforced concrete slab 12 to the ground surface and compacting it;

[0071] The cavity left between the top surface of the precast concrete pipe 11 and the top surface of the abandoned pipe pile 6 is used to reserve space for the ground 7 to settle, so that the settlement speed of the ground 7 above the abandoned pipe pile 6 is consistent with the settlement speed of the surrounding ground 7.

[0072] For the first embodiment of the method for reducing the surrounding soil settlement of the basement outer pipe piles of the present invention, the mechanism 1 for reducing the surrounding soil settlement and the construction method for promoting the settlement of the ground 7 above the abandoned pipe piles 6 are provided; first, by providing the mechanism 1 for reducing the surrounding soil settlement above the abandoned pipe piles 6, the settlement speed of the ground 7 above the abandoned pipe piles 6 is effectively controlled, so that the settlement speed of the ground 7 above the abandoned pipe piles 6 is kept consistent with that of the surrounding ground 7; in the first synchronous settlement stage of the ground 7, the damage to the municipal and garden supporting facilities caused by the difference in settlement is avoided. This synchronous settlement design of the ground 7 in different areas significantly improves the stability and safety of the municipal and garden supporting facilities and the ground 7.

[0073] Secondly, the present invention uses the precast concrete pipe 11 and the foundation sand 13 to form a buffer structure, wherein the foundation sand 13 is used as a filling material and has good compression resistance and uniform settlement performance. By filling the foundation sand 13 between the precast concrete pipe 11 and the abandoned pipe pile 6, the direct effect of the ground 7 pressure on the abandoned pipe pile 6 is further alleviated, and the risk of uneven settlement of the ground 7 is reduced.

[0074] Thirdly, by using prefabricated concrete pipes 11 and prefabricated reinforced concrete slabs 12 in the construction, the efficiency of the construction process and the standardization of materials are ensured. This prefabricated component reduces the complexity of on-site processing, shortens the construction period, and improves the construction quality and reliability. Moreover, local materials can be used, and the prefabricated concrete pipes 11 can also be replaced by concrete drainage pipes; in addition, the concrete material has a long service life, which enhances the durability of the entire structure.

[0075] During the construction process, there are multiple layers of protection measures. Cement mortar is applied to the top of the precast concrete pipe 11 and covered with a precast reinforced concrete slab 12 to prevent soil from being squeezed into the gap between the precast concrete pipe 11 and the precast reinforced concrete slab 12 under the pressure of the ground 7, thereby preventing erosion and reducing the cavity reserved for the settlement of the ground 7 on the inner wall of the precast concrete pipe 11, further increasing the time for the ground 7 above the abandoned pipe pile 6 to settle synchronously with the surrounding ground 7. By backfilling earth 21 to the surface and compacting it on the precast reinforced concrete slab 12, not only the soil layer on the surface of the ground 7 is restored, but also the flatness and stability of the surface are ensured, and the depression or collapse of the ground 7 caused by uneven settlement is avoided.

[0076] Finally, a cavity is reserved between the top surface of the precast concrete pipe 11 and the top surface of the abandoned pipe pile 6, providing a buffer space for the settlement of the ground 7, avoiding excessive pressure accumulation of concrete stress on the ground 7 above the abandoned pipe pile 6 due to insufficient settlement, thereby effectively improving the integrity of the concrete on the ground 7 above the abandoned pipe pile 6, thereby avoiding cracking of the ground 7. This design concept has strong adaptability and is particularly suitable for foundation treatment under complex geological conditions outside the basement.

[0077] In summary, the present invention significantly improves the settlement integrity, safety and uniformity of the ground 7 above the abandoned pipe piles 6 and the surrounding ground 7, effectively reduces the impact of the abandoned pipe piles 6 on municipal and garden supporting facilities, and has broad engineering application value.

[0078] In addition, if Figure 2 and Figure 3 The shape of the prefabricated reinforced concrete slab 12 can be a square slab or a circular slab. The prefabricated concrete pipe 11 can be a concrete drainage pipe, so that the mechanism 1 for reducing and resisting the surrounding soil settlement has strong adaptability.

[0079] The second implementation method of reducing the basement perimeter pipe piles to resist the surrounding soil settlement is as follows Figure 4 and Figure 5 As shown, the difference between this embodiment and the first embodiment is that it also includes a plurality of satellite traction mechanisms 3, the satellite traction mechanisms 3 include a pile core 31, a pressure plate 32, a collar 33 and a first pull rope 34; the outer wall surface of the collar 33 and the lower end surface of the precast reinforced concrete slab 12 are provided with connecting ear plates 35; in step S1, 8 meters away from the excavation area 2, the excavation area is 12-15 times the area of ​​the precast reinforced concrete slab 12, to the satellite area 6.5 meters below the top surface of the abandoned pipe pile 6; the pile core 31 with a length of at least 4 meters is inserted at least 1 meter below the bottom end of the satellite area with the conical end of the pile core 31; the collar 33 is put outside the pile core 31, so that the collar 33 falls on the bottom end of the satellite area, and the ear plate 35 of the collar 33 is rotated to the ear plate 35 of the precast reinforced concrete slab 12; along the ear plate 35 of the collar 33 to the ear plate 3 of the precast reinforced concrete slab 12 5, excavate a first trench, the depth of which corresponds to the depth of the satellite area; place a first pull rope 34 in the first trench, and connect and fix the two ends of the first pull rope 34 to the ear plate 35 of the ring 33 and the ear plate 35 of the precast reinforced concrete slab 12 respectively; backfill the satellite area and the first trench with earthwork 21 to the top surface of the pile core 31; place the pressure plate 32 on the top surface of the pile core 31, and connect and fix the pile core 31 to the pressure plate 32; backfill the earthwork 21 on the pressure plate 32 and the first trench to the surface and compact it; after the settlement space reserved in the precast concrete pipe 11 is compressed, the satellite traction mechanism 3 bears the pressure of the earthwork 21 above it by means of the pressure plate 32, and multiple satellite traction mechanisms 3 are combined and apply downward pulling force to the abandoned pipe pile 6 through their respective rings 33 and the first pull rope 34, and the abandoned pipe pile 6 gradually sinks under the pulling force.

[0080] Among them, the pile core 31, the pressure plate 32 and the wing plate 321 are all precast concrete components, wherein the pressure plate 32 and the wing plate 321 are cast as one piece; a threaded rod is provided at the axis of the pile core 31, and a connecting through hole is provided at the center of the pressure plate 32; when the pile core 31 and the pressure plate 32 are assembled, the threaded rod is passed through the connecting through hole, and the pile core 31 and the pressure plate 32 are locked by a nut.

[0081] And the first pull rope 34 connects the ear plate 35 of the ring 33 and the ear plate 35 of the prefabricated reinforced concrete slab 12 in a pre-tensioned manner.

[0082] During application, when the satellite traction mechanism 3 is pre-buried, the first pull rope 34 connects the ear plate 35 of the ring 33 and the ear plate 35 of the precast reinforced concrete slab 12 in a pre-tensioned manner, and the ring 33 is sleeved on the pile core 31. The ring 33 can slide on the pile core 31. As the reserved settlement space in the precast concrete pipe 11 of the mechanism 1 for resisting the settlement of the surrounding soil disappears, the second ground 7 synchronous settlement stage is entered, and the ring 33 slides up with the sinking of the pressure plate 32 and the pile core 31, and arrives under the pressure plate 32, and finally the ring 33 and the pull rope, under the limitation of the pressure plate 32 and the pile core 31, apply a downward pulling force to the precast reinforced concrete slab 12 of the mechanism 1 for reducing and resisting the settlement of the surrounding soil, and the mechanism 1 for reducing and resisting the settlement of the surrounding soil transmits the vertical downward pulling force provided by the multiple satellite traction mechanisms 3 to the abandoned pipe piles 6, so that the abandoned pipe piles 6 gradually sink in the second synchronous settlement stage of the ground 7, thereby reducing the impact on the municipal and garden supporting facilities caused by the asynchronous settlement speed of the abandoned pipe piles 6 and the surrounding ground 7 after entering the second stage.

[0083] As one optional implementation,

[0084] The satellite traction mechanism 3 can provide enough pulling force to make the abandoned pipe pile 6 sink slowly and gradually. Figure 5 As shown, at least eight satellite traction mechanisms 3 are provided and are evenly arranged around the axis of the mechanism 1 for reducing and resisting the surrounding soil settlement.

[0085] The area of ​​the pressure plate 32 is 12-15 times the area of ​​the precast reinforced concrete plate 12. The precast reinforced concrete plate 12 has a thickness of at least 150 mm and is cast using concrete with a grade of at least C35.

[0086] When in use, the eight satellite traction mechanisms 3 are able to target pipe piles with a diameter of 300-500 mm and a length of 20-30 meters; by utilizing geological subsidence and the dynamic pressure of the ground 7, the vertical downward pulling force provided to the satellite traction mechanism 3 on the abandoned pipe pile 6 can make the target abandoned pipe pile 6 and the ground 7 sink as synchronously as possible.

[0087] Regarding the use of the additional structure of the pressure plate 32 and the second pull rope 4 to prevent the single pressure plate 32 and the pile core 31 from gradually tilting under the action of the tension of the first pull rope 34, for example, Figure 5 As shown, wing plates 321 are provided on two adjacent surfaces of the pressure plate 32, and the two wing plates 321 are arranged toward the mechanism 1 for reducing and resisting the settlement of the surrounding soil; the wing plates 321 are used to prevent the pile core 31 and the pressure plate 32 from tilting inward toward the mechanism 1 for reducing and resisting the settlement of the surrounding soil when the ring 33 applies tension to the first pull rope 34.

[0088] Specifically, a second groove is excavated between adjacent satellite areas, a second pull rope 4 is placed in the second groove, and two ends of the second pull rope 4 are connected to the ear plates 35 of two adjacent rings 33 in a pre-tensioned manner.

[0089] During application, by setting a wing plate 321 on the pressure plate 32, the combination of a single pressure plate 32 and a pile core 31 is improved to maintain its own vertical support force, thereby preliminarily preventing the combination of a single pressure plate 32 and a pile core 31 from twisting and tilting when a pulling force is applied to the mechanism 1 for reducing the surrounding soil settlement and the abandoned pipe pile 6; the combination of multiple pressure plates 32 and pile cores 31 is connected by a second pull rope 4, and the first pull rope 34 is connected to the prefabricated reinforced concrete slab 12, so that multiple satellite traction mechanisms 3 can form an umbrella structure around the abandoned pipe pile 6. The integrity of the multiple satellite traction mechanisms 3 is improved to restrict the single one as a whole, further preventing the combination of a single pressure plate 32 and a pile core 31 from twisting and tilting.

[0090] The third implementation method of reducing the basement perimeter pipe piles to resist the surrounding soil settlement is as follows Figure 6 As shown, the difference between this embodiment and the second embodiment is that the multiple satellite traction mechanisms 3 arranged around a single abandoned pipe pile 6 form a group of pipe pile sinking groups 5; it also includes a third pull rope 51, each adjacent abandoned pipe pile 6 is respectively arranged with a group of pipe pile sinking groups 5, and the multiple pipe pile sinking groups 5 are connected by the third pull rope 51; the two ends of the third pull rope 51 are respectively connected to the ear plates 35 of the adjacent rings 33.

[0091] During application, (a) when there are multiple abandoned pipe piles 6 at the construction site, a group of pipe pile sinking groups 5 are provided on each of the multiple abandoned pipe piles 6, and the pressure plates 32 and pile cores 31 of adjacent pipe pile sinking groups 5 can be connected to the ear plates 35 on the other side of the rings 33 through the third pull rope 51, so that the adjacent rings 33 can obtain tension in at least two directions, preventing the pressure plates 32 and the pile cores 31 from twisting and tilting, and at the same time enhancing the overall sinking force of the abandoned pipe piles 6.

[0092] (b) If the diameter of the abandoned pipe pile 6 is too large and the length is too long, exceeding the pulling force of the pipe pile sinking group 5 to pull the abandoned pipe pile 6 down, then multiple pipe pile sinking groups 5 are jointly fixed by a third pull rope 51, which can enable the entire covered ground 7 to achieve overall settlement under the support of the abandoned pipe piles 6.

[0093] (c) If the area of ​​the ground 7 that needs to control the settlement is too large, the abandoned pipe piles 6 also have a certain coverage area. For the ground 7 that lacks abandoned pipe piles 6, new pipe piles can be added, and then all of them can be arranged to reduce the settlement of the surrounding soil. The mechanism 1 can be used to resist the settlement of the surrounding soil. After all the pipe pile sinking groups 5 are arranged, they can be connected by the third pull rope 51. The abandoned pipe piles 6 and the new pipe piles can be combined to support the ground 7, so that the ground 7 forms a whole, and the damage caused by cracks in municipal and garden supporting facilities due to settlement differences can also be avoided.

[0094] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described.

Claims

1. A method for reducing the surrounding soil settlement by using pipe piles outside a basement, characterized in that: It includes a mechanism for reducing and resisting the settlement of surrounding soil for controlling the earthwork and ground settlement velocity above the abandoned pipe piles and the abandoned pipe piles below the ground settlement velocity to be controlled; The mechanism for reducing and resisting the surrounding soil settlement is composed of precast concrete pipes, precast reinforced concrete slabs and foundation sand; The construction steps include: S1: Find the location of the abandoned pipe pile foundation, excavate the ground surface, and excavate to a depth of 3 meters below the top surface of the abandoned pipe pile, and the diameter of the excavation area is 4 times the diameter of the abandoned pipe pile; S2: leveling the bottom of the excavation area; S3: Filling the foundation sand into the excavation area until the foundation sand is flush with the top surface of the abandoned pipe pile; S4: lowering the precast concrete pipe to the excavation area, so that the precast concrete pipe is sleeved outside the abandoned pipe pile, and the abandoned pipe pile is located in the center area of ​​the precast concrete pipe; the length of the lower precast concrete pipe is 2.5-3 meters; S5: Pressing the precast concrete pipe into the foundation sand to a depth of one fifth of the length of the precast concrete pipe, so that there is foundation sand between the precast concrete pipe and the abandoned pipe pile, and a cavity is left between the top end surface of the precast concrete pipe and the top end surface of the abandoned pipe pile; S6: Stabilize the precast concrete pipe, and backfill earth between the precast concrete pipe and the excavation area until the earth is flush with the top surface of the precast concrete pipe; S7: applying a layer of cement mortar to the top surface of the precast concrete pipe; S8: Covering the precast reinforced concrete slab on the top surface of the precast concrete pipe, the area of ​​the precast reinforced concrete slab is larger than the cross-sectional area of ​​the precast concrete pipe; S9: backfilling soil onto the prefabricated reinforced concrete slab to the ground surface and compacting it; The cavity left between the top end surface of the precast concrete pipe and the top end surface of the abandoned pipe pile is used to reserve space for ground settlement, so that the ground settlement speed above the abandoned pipe pile is consistent with the settlement speed of the surrounding ground.

2. The method for reducing the surrounding soil settlement by using pipe piles outside the basement according to claim 1 is characterized in that: It also includes a plurality of satellite traction mechanisms, the satellite traction mechanisms including a pile core, a pressure plate, a collar and a first pull rope; the outer wall surface of the collar and the lower end surface of the prefabricated reinforced concrete slab are provided with connecting ear plates; In step S1, a satellite area is excavated at a radius of 8 meters from the excavation area, with an area of ​​12-15 times the area of ​​the prefabricated reinforced concrete slab, to a depth of 6.5 meters below the top surface of the abandoned pipe pile; Inserting the pile core having a length of at least 4 meters at a point at least 1 meter below the bottom end of the satellite area with the conical end of the pile core; Put the collar on the outside of the pile core so that the collar falls on the bottom of the satellite area, and rotate the ear plate of the collar to face the ear plate of the prefabricated reinforced concrete slab; excavating a first trench along a straight path from the ear plate of the collar to the ear plate of the prefabricated reinforced concrete slab, wherein the depth of the first trench corresponds to the depth of the satellite area; Placing the first draw rope in the first groove, so that two ends of the first draw rope are respectively connected and fixed to the ear plate of the ring and the ear plate of the prefabricated reinforced concrete slab; Backfilling the satellite area and the first trench with earth to the top surface of the pile core; Placing the pressure plate on the top surface of the pile core, and connecting and fixing the pile core to the pressure plate; backfilling earth on the pressure plate and the first groove to the ground surface and compacting it; After the settlement space reserved in the precast concrete pipe is compressed, the satellite traction mechanism bears the earth pressure above it with the help of the pressure plate, and multiple satellite traction mechanisms are combined to apply downward pulling force to the abandoned pipe pile through their respective rings and the first pull rope. The abandoned pipe pile gradually sinks under the pulling force.

3. The method for reducing the surrounding soil settlement by using pipe piles outside the basement according to claim 2 is characterized in that: The first pull rope connects the ear plate of the ring and the ear plate of the prefabricated reinforced concrete slab in a pre-tensioned manner.

4. The method for reducing the surrounding soil settlement by using pipe piles outside the basement according to claim 2 is characterized in that: At least eight satellite traction mechanisms are provided and are evenly arranged around the axis of the mechanism for reducing and resisting surrounding soil settlement.

5. The method for reducing the surrounding soil settlement by using pipe piles outside the basement according to claim 4 is characterized in that: A second groove is excavated between adjacent satellite areas, a second pull rope is placed in the second groove, and two ends of the second pull rope are connected to the ear plates of two adjacent rings in a pre-tensioned manner.

6. The method for reducing the surrounding soil settlement by using pipe piles outside the basement according to claim 5 is characterized in that: Wing plates are arranged on two adjacent surfaces of the pressure plate, and the two wing plates are arranged toward the mechanism for reducing and resisting the settlement of the surrounding soil; the wing plates are used to prevent the pile core and the pressure plate from tilting inward toward the mechanism for reducing and resisting the settlement of the surrounding soil when the ring applies tension to the first pull rope.

7. The method for reducing the surrounding soil settlement by using pipe piles outside a basement according to claim 6 is characterized in that: The pile core, the pressure bearing plate and the wing plate are all precast concrete components, wherein the pressure bearing plate and the wing plate are cast in one piece; A threaded rod is provided at the axis of the pile core, and a connecting through hole is provided at the center of the pressure plate; When the pile core is assembled with the pressure plate, the threaded rod is passed through the connecting through hole, and the pile core and the pressure plate are locked by a nut.

8. The method for reducing the surrounding soil settlement by using pipe piles outside a basement according to claim 5 is characterized in that: The plurality of satellite traction mechanisms arranged around a single abandoned pipe pile constitute a pipe pile sinking group; It also includes a third pull rope, each adjacent abandoned pipe pile is respectively arranged with a group of the pipe pile sinking groups, and the plurality of pipe pile sinking groups are connected by the third pull rope; Two ends of the third pull rope are respectively connected to the ear plates of the adjacent rings.

9. The method for reducing the surrounding soil settlement by using pipe piles outside a basement according to claim 2 is characterized in that: The area of ​​the pressure-bearing plate is 12-15 times the area of ​​the prefabricated reinforced concrete slab.

10. The method for reducing the surrounding soil settlement by using pipe piles outside a basement according to claim 2 is characterized in that: The prefabricated reinforced concrete slab has a thickness of at least 150 mm and is cast using concrete with a grade of at least C35.

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