CN111364479A - Inclined support threaded pile supporting structure for foundation pit enclosure and construction method thereof - Google Patents

Abstract

The invention discloses a diagonal bracing threaded pile supporting structure for foundation pit bracing, which comprises a bracing pile, a foundation slab and a plurality of threaded piles, wherein the foundation slab is positioned below a soil layer, the upper end of each threaded pile is connected with the upper end of the bracing pile, each threaded pile penetrates through the foundation slab and at least partially enters the bracing force soil layer below the foundation slab, the threaded piles are gradually inclined from top to bottom, and the diagonal bracing threaded pile supporting structure is characterized in that: a water stopping sleeve is arranged at the penetrating position of the threaded pile in the foundation bottom plate, and the water stopping sleeve is arranged on the periphery of the threaded pile and is detachably connected with the threaded pile. Also discloses a construction method of the inclined support threaded pile supporting structure. Compared with the prior art, the invention has the advantages that: through set up stagnant water sleeve pipe, stagnant water sleeve pipe and screw pile in the soleplate can dismantle and be connected, the screw pile of can being convenient for is demolishd and is retrieved, has reduced construction cost, need not to consider the problem of construction joint, and later stage structure is handled portably, the quality is reliable.

Description

Inclined support threaded pile supporting structure for foundation pit enclosure and construction method thereof

Technical Field

The invention relates to the field of foundation pit bracing, in particular to an oblique support threaded pile supporting structure for foundation pit bracing and a construction method of the structure.

Background

In deep foundation pit engineering, a supporting system is often required to be added to increase the safety and stability of the foundation pit engineering, ensure that the surrounding environment of the foundation pit, engineering piles in the foundation pit and the like are not affected, and also ensure the safety of constructors, machinery and the like. At present, several support forms are common: horizontal bracing, bracing and anchor.

The horizontal support is the most widely applied support form of the current deep foundation pit, but the horizontal support has the advantages of large span, long construction period, high cost and complex support structure system, and is not beneficial to earth excavation and main structure construction. Meanwhile, the support form needs to be completely dismantled in the later period, so that the environmental pollution is serious, and a plurality of potential safety hazards exist.

The common anchoring and pulling methods such as a rotary spraying anchor rod cable or a soil nailing wall are adopted, but the supporting mode is not suitable for foundation pits with poor soil property or deeper excavation such as soft soil, the safety coefficient is low, and the potential safety hazard of construction quality is large; and because the anchoring length is longer, the anchor often needs to extend out of the range of dozens of meters or dozens of meters of the red line of the building, and the surrounding environment of the site has considerable restriction on the anchor.

At present, common inclined struts such as reinforced concrete, steel pipes or profile steel inclined struts are supported on a basement bottom plate, and the common inclined struts are economical. The support form is commonly used in construction areas or local reinforced parts after central island excavation and secondary enclosure, the support form can only play a role when the strength of a basement bottom plate reaches over 75 percent, the construction period is long, and the deformation control reaction is slow. Later dismantling and structural processing at the place are difficult.

The application number 201410107071.1 discloses an oblique supporting pile structure for foundation pit enclosure and a construction method thereof, wherein the structure comprises an enclosure pile, a crown beam, a foundation pit bottom plate, a building structure, an oblique supporting pile, a water stop device and a soil improvement structure, wherein the oblique supporting pile is obliquely implanted into original soil below the foundation pit bottom plate at a certain angle, and the original soil is hardened by a high-pressure jet grouting pile or a soil curing agent; the top end of the inclined support pile and the top end of the fender pile are fixedly connected and embedded into the top beam, the top beam is integrally cast in place, and a water stop ring is arranged at the position of penetrating through the bottom plate of the building structure and the shear wall.

Compared with a horizontal support, the invention can be beneficial to earth excavation and shortening the construction period, and can save the construction period compared with the traditional throwing support; however, the device of the patent is disposable, cannot be recycled, cannot save materials, and tends to increase the cost of the foundation pit; although soil improvement is carried out on the soil at the bottom of the support, the H-shaped steel structure, the steel lattice column structure or the steel pipe structure is adopted to provide oblique supporting force by means of friction resistance, the supporting effect is still difficult to guarantee, particularly in a saturated soft soil area, and water leakage of a later basement structure or the durability of the structure is affected after the H-shaped steel structure, the steel lattice column structure or the steel pipe structure is cut off; the support can not provide effective adjustment and reinforcement measures when the foundation pit is greatly deformed, and can be solved after additional measures or reinforcement measures are needed, so that the treatment efficiency is very unfavorable for projects with larger risks, such as the foundation pit.

However, as the surrounding environment of the foundation pit is more and more complicated at present, for example: peripheral standing buildings are close to the red line of the buildings, the number of the pipelines around the foundation pit is large, and the deformation of the material yard processing area close to the foundation pit is caused after the ground is narrow. When the deformation of the foundation pit is large, the situation that the reinforcement guarantee cannot be provided through the enclosure is often caused, and the deformation can be controlled only by additionally arranging an external supporting system.

In addition, "building saving materials and accelerating the building of a saving society" is a basic national policy which is insisted by China for a long time, and the pursuit of project investors is more to reduce the cost of the foundation pit on the premise of ensuring the safety of the foundation pit. The traditional foundation pit engineering has the phenomenon of wasting a plurality of materials and artificial resources, and the supporting form has large engineering quantity, high manufacturing cost and serious solid dust pollution in the later period.

For this reason, further improvement is required.

Disclosure of Invention

The invention aims to solve the first technical problem and provides an inclined support threaded pile support structure for foundation pit enclosure, which can provide high support force, can be used for reinforcement and adjustment according to the deformation condition of a foundation pit and is convenient to recycle.

The second technical problem to be solved by the invention is to provide a construction method of the inclined support threaded pile supporting structure.

The technical scheme adopted by the invention for solving the first technical problem is as follows: the utility model provides a diagonal bracing screw thread stake supporting construction for foundation ditch enclosure, includes a fender pile, is located the foundation slab and a plurality of screw thread stake of soil layer below, and the upper end of every screw thread stake is connected with the upper end of a fender pile, and every screw thread stake passes foundation slab and at least part entering foundation slab below propping power soil layer from the foundation slab top, the screw thread stake from top to bottom inclines its characterized in that gradually in opposite directions gradually: a water stopping sleeve is arranged at the penetrating position of the threaded pile in the foundation bottom plate, and the water stopping sleeve is arranged on the periphery of the threaded pile and is detachably connected with the threaded pile.

Preferably, for the recovery of returning soon of screw pile, the water stopping sleeve inboard is provided with the internal thread to with screw pile threaded connection, be convenient for return soon when screw pile rotatory is retrieved, the internal thread in the water stopping sleeve also is favorable to increasing foundation slab's stagnant water nature.

Preferably, the wall thickness of the water stop sleeve is more than or equal to 2.0mm in order to provide enough supporting force.

Preferably, in order to control the deformation of the foundation pit conveniently, the upper end of the support pile is provided with a crown beam, and the crown beam is connected with the threaded pile through an adjustable anchoring device.

Preferably, in order to facilitate connection of the crown beam and the threaded piles, brackets connected with the threaded piles are arranged at intervals in the direction of the crown beam, and holes or open grooves for the end portions of the threaded piles to enter are formed in the crown beam.

Preferably, in order to provide better inclined supporting force and pulling-resistant bearing capacity and facilitate removal, each threaded pile comprises a first threaded pile section and a second threaded pile section which are connected with each other, the first threaded pile section is located above the second threaded pile section, the second threaded pile section penetrates through the foundation slab and is screwed into the soil layer, the second threaded pile section is connected with the water stop sleeve and is mechanically meshed with the soil layer through a screw blade, and the width of the screw blade of the second threaded pile section is larger than or equal to 120 mm.

The technical scheme adopted by the invention for solving the second technical problem is as follows: the construction method of the inclined support threaded pile supporting structure comprises the following steps:

1) and (3) supporting pile construction: constructing a support pile around the foundation pit, and pouring a crown beam connected with the threaded pile at the upper end part of the support pile;

2) installing a threaded pile: connecting the first threaded pile section and the second threaded pile section with each other to form an integral threaded pile, and screwing the threaded pile into a soil layer at a certain angle until the threaded pile reaches a certain depth below a foundation slab required by design;

3) detecting the bearing capacity: extracting a plurality of threaded piles to detect the inclined compression bearing capacity, and simultaneously determining the support allowance of the threaded piles;

4) anchoring the threaded pile: treating the anchoring position of the screw pile, sleeving the anchoring device, and after the concrete strength of the crown beam reaches a certain degree, uniformly screwing and anchoring the screw pile and the crown beam at intervals along the foundation pit through the anchoring device, so that the support pile and the screw pile form an integral structure with interaction force;

5) excavating a foundation pit: after the crown beam reaches a certain strength, carrying out foundation pit earthwork excavation;

6) constructing a foundation slab: after the foundation pit is excavated, constructing a foundation slab, and placing and fixing a water stop sleeve in the foundation slab when the foundation slab is constructed;

7) removing the threaded pile: after the foundation slab construction is finished and the support dismantling conditions required by the enclosure design are met, the anchoring devices are unscrewed at intervals, the foundation pit deformation monitoring is carried out immediately, the threaded piles are dismantled and recycled if the data are stable, and the foundation pit is reinforced by taking measures to ensure the safety of the foundation pit if the data are unstable.

Preferably, in order to control the deformation of the foundation pit, in steps 5) and 6), if the deformation of the foundation pit exceeds the value required by the enclosure design and the specification, the deformation of the foundation pit is controlled by further screwing and screwing the anchoring device, and then no reinforcement measure is needed if the deformation of the foundation pit is controlled, and the reinforcement measure is needed if the deformation of the foundation pit is not controlled.

Preferably, in step 7), when the threaded piles are dismantled, the dismantling and recycling are carried out one by one, each threaded pile unloads the first threaded pile section, and the second threaded pile section is screwed and recycled after the water stop sleeve is cleaned.

Preferably, in order to prevent the foundation slab from leaking water, a screw plate matched with the screw blade of the screw pile is arranged on the inner wall of the water stop sleeve, and the inside of the water stop sleeve is sealed by concrete after the screw pile is recovered.

Compared with the prior art, the invention has the advantages that: the water stop sleeve is arranged in the foundation bottom plate and detachably connected with the threaded pile, so that the threaded pile can be conveniently detached and recovered, the construction cost is reduced, the problem of construction joints does not need to be considered, the post-structure treatment is simple and convenient, and the quality is reliable; the threaded piles and the support piles are connected through the adjustable anchoring devices, self-adjustment can be carried out according to the deformation condition of the foundation pit during the earth excavation and foundation construction, and the safety of the foundation pit is guaranteed; the construction process of the enclosure structure and the construction process of the inclined support structure have no precedence, so that the construction period can be greatly shortened; the supporting system does not need a large amount of reinforced concrete structures; the barrier-free excavation and structural construction can be realized; when the inclined supporting system is dismantled, unloading and monitoring can be carried out simultaneously, and the problem of uneven stress release or instantaneous unloading caused by dismantling of the support is effectively solved.

Drawings

Fig. 1 is a schematic view of an inclined support threaded pile supporting structure according to an embodiment of the present invention;

fig. 2 is a sectional view of a water-stopping internal thread bushing of the inclined support threaded pile supporting structure according to the embodiment of the invention;

fig. 3 is a diagram of a connection node of two sections of screw piles of a support structure for an inclined support screw pile according to an embodiment of the present invention;

fig. 4 is a diagram of a connection node between a screw pile and a crown beam of the slant support screw pile supporting structure according to the embodiment of the present invention;

fig. 5 is a partial schematic view of a screw pile of the slant support screw pile supporting structure according to the embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar functions.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present invention and to simplify the description, but are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and that the directional terms are used for purposes of illustration and are not to be construed as limiting, for example, because the disclosed embodiments of the present invention may be oriented in different directions, "lower" is not necessarily limited to a direction opposite to or coincident with the direction of gravity. Furthermore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

Referring to fig. 1, an inclined support threaded pile supporting structure for foundation pit bracing includes a support pile 1, a foundation slab 2 and a threaded pile 3. The supporting piles 1 extend longitudinally, the foundation slab 2 is positioned below the soil layer and at the bottom of the foundation pit, and a support replacing belt 21 which is convenient for force transmission is arranged between the periphery of the foundation slab and the supporting piles 1.

Referring to fig. 1 and 3, the threaded pile 3 has a plurality of, steel pipes made of metal, and each threaded pile 3 includes a first threaded pile section 31 and a second threaded pile section 32, wherein the first threaded pile section 31 is located above the second threaded pile section 32, and a lower end of the first threaded pile section 31 and an upper end of the second threaded pile section 32 are connected to form the complete threaded pile 3. The first threaded pile section 31 and the second threaded pile section 32 are in threaded connection through a steel pipe sleeve, reinforcement processing is carried out at a connection node, and the first threaded pile section and the second threaded pile section can be dismantled and recycled in sections during dismantling. The upper end of each screw pile 3 is connected with the upper end of the support pile 1, and the lower end of each screw pile 3 enters a supporting soil layer below the foundation bottom plate 2. Each screw pile 3 is inclined at a certain angle with the vertical direction and penetrates through the elevation of the foundation bottom plate 2 to enter a soil layer in a screwing mode. Two screw piles 3 are gradually inclined from top to bottom in opposite directions.

Referring to fig. 1 and 4, the upper end of the support pile 1 is provided with a crown beam 11, a hole or an open slot 12 is reserved on the crown beam 11, the upper end of a first threaded pile section 31 is connected with the crown beam 11 through an anchoring device 13, and the upper end part of the first threaded pile section 31 enters the hole or the open slot 12. The anchoring means 13 is preferably an adjustable nut. Thereby, the screw pile 3 is integrated with the support pile 1. If the later stage foundation pit is deformed greatly, the anchoring device 13 can be screwed and fastened by screwing to achieve the effect of controlling the deformation of the foundation pit. Preferably, a bracket 14 made of reinforced concrete or steel structure is arranged at the crown beam 11. The bracket 14 is arranged at 90 degrees to the threaded pile 3, so that the anchoring device 13 is convenient to fix and adjust later.

Referring to fig. 5, the screw pile 3 belongs to an irregular pile, and is embedded into soil body through screw threads formed along the periphery of a pile body, so that the stress form is greatly improved. The first threaded pile section 31 can be a shallow thread or a plain circular steel tube, but is provided with a shallow and thick thread in the anchoring area with the crown beam 11 and is provided with an anchoring device 13 of a corresponding type. The second screw thread pile section 32 adopts wide screw blades, the majority of the oblique supporting force is provided by the spiral linear pile end bearing formed by the mechanical engagement of the screw blades of the screw thread pile 3 and the soil body, and the overall rigidity can be improved by increasing the thickness of the screw blades, so that the great oblique supporting force and the anti-pulling bearing capacity can be provided.

The soil layer at the lower end of the screw pile 3 is determined according to the physical and mechanical properties, if the soil layer is supported in a granular soil layer, the soil body can be sheared and compacted by screwing the screw leaves of the screw pile 3, and high supporting force can be provided; in a soil layer with better shearing resistance, as long as the soil body is not disturbed, the threaded pile 3 is screwed in and screwed out by depending on a fixed thread path, so that high supporting force can be provided; when the physical and mechanical properties of the soil layer are poor, such as soft soil, a grouting pipe can be arranged in the inner cavity of the steel pipe of the threaded pile 3, and grouting holes 321 are formed in the steel pipe wall of the second threaded pile section 32 and the position of the drill bit, so that the soil layer is reinforced by spraying cement slurry while stirring along with the screwing of the threaded pile 3, and a hard soil supporting structure is formed.

Preferably, the wall thickness of the screw pile 3 is 5-15 mm, the diameter of the steel pipe is more than or equal to 80mm, the thickness of the screw blade is more than or equal to 3.5mm, the width of the screw blade is determined according to engineering tests, and the preferred width is more than or equal to 120 mm.

Referring to fig. 1 and 2, a water stop sleeve 4 is arranged in the foundation slab 2 at a position penetrated by the second threaded pile section 32, and the water stop sleeve 4 is positioned on the periphery of the second threaded pile section 32. The water stopping sleeve 4 is preferably two semicircular pipe fittings which are spliced into a whole circle by welding and arranged on the periphery of the threaded pile 3. Through setting up stagnant water sleeve pipe 4, one then has played the effect of later stage stagnant water, and two then can make 3 later stages of screw pile revolve back and receive the utilization through the setting of stagnant water sleeve pipe 4. The water stop sleeve 4 has an internal thread, and the second threaded stub portion 32 passes through the water stop sleeve 4 and is screwed. The internal thread of the water stop sleeve 4 also contributes to increasing the water stopping property of the foundation sole plate 2. The welding of the 4 periphery circles of stagnant water sleeve pipe has the reinforcing bar to strengthen being connected of stagnant water sleeve pipe 4 and soleplate 2, inside then set up with the spiral shell leaf assorted spiral shell board 41 of screw pile 3, the internal thread forms on spiral shell board 41, later stage accessible is higher than soleplate 2 a grade standard height's micro-expansion concrete and seals stagnant water sleeve pipe 4, avoids soleplate 2 problem of leaking from this.

Preferably, the wall thickness of the water stop sleeve 4 is more than or equal to 2.0mm, the pitch and the screw width of the internal thread inside the water stop sleeve need to correspond to those of the second threaded pile section 32, and the embedding angle needs to be the same as that of the threaded pile 3. The water stop sleeve 4 needs to be sleeved into the foundation slab 2 before the threaded pile 3 is fixed, and later protective measures are taken. When the water stop sleeve 4 is connected with the foundation slab 2, the periphery of the water stop sleeve needs to be welded and fixed by adopting reinforcing steel bars, so that dislocation or damage during construction of the foundation slab 2 is prevented, and the later-stage threaded pile 3 cannot be screwed and recycled.

Alternatively, the inner side wall surface of the water stopping sleeve 4 can also be a smooth surface, and the threaded pile 3 penetrates through the water stopping sleeve 4 and can move relative to the water stopping sleeve 4. The water stopping sleeve 4 can be provided with an annular water stopping steel plate strip on the inner side wall surface to play a water stopping role. As long as set up stagnant water sleeve pipe 4 in foundation slab 2, be non-fixed detachable connected mode between stagnant water sleeve pipe 4 and the screw pile 3, can realize that revolving of screw pile 3 moves back and retrieve.

The construction method of the inclined support threaded pile supporting structure comprises the following steps:

1) and (3) constructing a support pile 1: constructing a support pile 1 around a preset foundation pit, pouring a reinforced concrete crown beam 11 at the upper end part of the support pile 1, arranging reinforced concrete corbels 14 at certain intervals along the direction of the crown beam 11, reserving holes or open slots 12 on the crown beam 11 to form straight-through holes for screwing the threaded piles 3, wherein the positions and the number of the corbels 14 respectively correspond to the holes or the open slots 12; the distance between the brackets 14 is equal to that between the threaded piles 3, and reinforcing steel bars are preferably arranged at the top beam 11;

2) installing the threaded pile 3: connecting a first threaded pile section 31 and a second threaded pile section 32 with each other to form an integral threaded pile 3, and screwing the threaded pile 3 into a soil layer at a certain angle by using a drilling machine until the threaded pile reaches a certain depth (a certain depth below the soil layer) below a foundation slab 2 required by the design; in the embodiment, the soil layer is granular soil, and high-pressure grouting is not needed for reinforcing the soil layer after the soil layer is screwed in place; the drilling machine is preferably a drilling machine with an angle adjustable by 90 degrees, the length, the screw blade distance, the screw blade width and the like of the second threaded pile section 32 providing the supporting force need to be subjected to oblique compression detection in advance to determine standards, and an isolation sleeve needs to be arranged in an upper-section earth excavation area during detection, so that reliable supporting force data can be measured;

3) detecting the bearing capacity: extracting a plurality of threaded piles 3 to detect the inclined compression bearing capacity so as to ensure the safety of the foundation pit; when the compression resistance detection is carried out, a pressurizing device can be arranged at the position of the bracket 14 to ensure that the applied force and the threaded pile 3 are on the same stress axis; during detection, the support allowance of the threaded pile 3 is required to be determined so as to ensure that the allowance can be used for self-adjusting and reinforcing when the foundation pit is greatly deformed in the later period;

4) anchoring the threaded pile 3: treating the anchoring position of the screw pile 3, sleeving the anchoring device 13, and after the concrete strength of the crown beam 11 reaches a certain degree, such as 75%, uniformly screwing and anchoring the screw pile 3 at intervals through the anchoring device 13 along the foundation pit, wherein at the moment, the support pile 1 and the screw pile 3 form an integral structure with interaction force;

5) excavating a foundation pit: after the crown beam 11 reaches a certain strength, earth excavation is carried out according to specifications and an earth excavation special construction scheme, as the inclined support threaded pile 3 is adopted and certain prestress can be exerted by screwing according to the conditions of the foundation pit and the earth excavation, the foundation pit earth excavation can be completely excavated to the designed elevation at one time, inclined support is not needed after local excavation, and then large-area earth excavation is carried out;

6) and (3) constructing a foundation slab 2: after the foundation pit is excavated, constructing a foundation bottom plate 2, such as cushion layer, brick bed film, bottom plate water proofing, bottom plate steel bar binding, support belt replacement and the like; when the foundation bottom plate 2 is constructed, the water stopping sleeve 4 is placed in the foundation bottom plate 2 and is firmly welded and fixed by adopting the steel bars, and the water stopping sleeve 4 is directly and integrally poured into the foundation bottom plate 2 when the foundation bottom plate 2 is poured with concrete; measures need to be taken in the pouring process to ensure that concrete and cement paste do not enter the water stop sleeve 4, and the second threaded pile section 32 can be smoothly screwed and recycled in the later period;

7) removing the threaded pile: after the foundation slab 2 is constructed and the support dismantling conditions required by the enclosure design are met, loosening the anchoring devices 13 at intervals, immediately monitoring the deformation of the foundation pit, dismantling and recovering the threaded piles 3 one by one if the data are stable, and adopting other reinforcement measures to ensure the safety of the foundation pit if the data are unstable; when the water-stopping sleeve 4 is removed, the first threaded pile section 31 is removed from each threaded pile one by one, and the second threaded pile section 32 is screwed and recovered after the water-stopping sleeve 4 is cleaned; after the screw pile 3 is recovered, high-grade micro-expansive concrete is adopted to close the pile hole, and maintenance work is well done;

in steps 5) and 6), if the deformation of the foundation pit is large and exceeds the numerical value required by the enclosure design and the specification, the deformation of the foundation pit can be controlled by further screwing and screwing the anchoring device 13, and then the deformation of the foundation pit is controlled without taking a reinforcing measure, and if the deformation of the foundation pit is not controlled, the reinforcing method is needed.

The inclined support threaded pile structure has recoverability, can provide high support force, can be reinforced and adjusted according to the deformation condition of the foundation pit, solves the problems of complex process, high manufacturing cost, resource waste and the like of the conventional foundation pit support, and ensures the safety, economy and environmental protection of foundation pit construction. After the inclined support is finished and the detection of the pressurizing support force is finished, the foundation pit can be excavated at one time, and the mechanical excavation operation space is large; when the foundation pit bottom plate is constructed, because the internal thread sleeve pipe of stagnant water has been buried underground, can with the integrative construction of slant support stake intersection position, utilize the inside unsmooth screw thread's of the outside stagnant water steel sheet of sleeve pipe structure can effectively solve this intersection position later stage problem of leaking water. When the inclined supporting system is dismantled, unloading and monitoring can be carried out simultaneously, and the problem of uneven stress release or instantaneous unloading caused by dismantling of the support is effectively solved.

Claims (10)

1. The utility model provides a diagonal bracing screw thread stake supporting construction for foundation ditch enclosure, includes fender pile (1), be located foundation slab (2) and a plurality of screw thread stake (3) of soil layer below, the upper end of every screw thread stake (3) is connected with the upper end of fender pile (1), and every screw thread stake (3) pass foundation slab (2) and at least part gets into the supporting force soil layer of foundation slab (2) below, screw thread stake (3) from top to bottom slope in opposite directions gradually, its characterized in that: a water stopping sleeve (4) is arranged at a penetrating position of the threaded pile (3) in the foundation bottom plate (2), and the water stopping sleeve (4) is arranged on the periphery of the threaded pile (3) and is detachably connected with the threaded pile (3).

2. The inclined support threaded pile supporting structure for foundation pit bracing of claim 1, wherein: the inner side of the water stop sleeve (4) is provided with internal threads so as to be in threaded connection with the threaded pile (3).

3. The inclined support threaded pile supporting structure for foundation pit bracing of claim 2, wherein: the wall thickness of the water stop sleeve (4) is more than or equal to 2.0 mm.

4. The inclined support threaded pile supporting structure for foundation pit bracing of claim 1, wherein: the upper end of the support pile (1) is provided with a crown beam (11), and the crown beam (11) is connected with the threaded pile (3) through an adjustable anchoring device (13).

5. The inclined support threaded pile supporting structure for foundation pit bracing according to claim 4, wherein: the bracket is characterized in that brackets (14) connected with the threaded piles (3) are arranged at intervals in the direction of the crown beam (11), and holes or open grooves (12) for the end parts of the threaded piles (3) to enter are formed in the crown beam (11).

6. The inclined support threaded pile supporting structure for foundation pit bracing of claim 1, wherein: each threaded pile (3) comprises a first threaded pile section (31) and a second threaded pile section (32) which are connected with each other, the first threaded pile section (31) is located above the second threaded pile section (32), the second threaded pile section (32) penetrates through the foundation slab (2) and is screwed into the soil layer, the second threaded pile section (32) is connected with the water stop sleeve (4) and is mechanically meshed with the soil layer through a screw blade, and the width of the screw blade of the second threaded pile section (32) is larger than or equal to 120 mm.

7. A construction method of an inclined support threaded pile supporting structure according to any one of claims 1 to 6, comprising the steps of:

1) constructing a support pile (1): constructing a support pile (1) around the foundation pit, and pouring a crown beam (11) for connecting with the threaded pile (3) at the upper end part of the support pile (1);

2) installing the threaded pile (3): connecting a first threaded pile section (31) and a second threaded pile section (32) with each other to form an integral threaded pile (3), and screwing the threaded pile (3) into a soil layer at a certain angle until reaching a certain depth below a foundation slab (2) required by the design;

3) detecting the bearing capacity: extracting a plurality of threaded piles (3) for detecting the inclined pressed bearing capacity, and simultaneously determining the support allowance of the threaded piles (3);

4) anchoring the threaded pile (3): treating the anchoring position of the screw-thread pile (3), sleeving an anchoring device (13), and after the concrete strength of the crown beam (11) reaches a certain degree, uniformly screwing and anchoring the screw-thread pile (3) and the crown beam (11) at intervals along the foundation pit through the anchoring device (13), so that the support pile (1) and the screw-thread pile (3) form an integral structure with interaction force;

5) excavating a foundation pit: after the crown beam (11) reaches a certain strength, performing foundation pit earthwork excavation;

6) constructing a foundation slab (2): after the foundation pit is excavated, constructing the foundation slab (2), and placing and fixing the water stop sleeve (4) in the foundation slab (2) when the foundation slab (2) is constructed;

7) removing the threaded pile (3): after the foundation slab (2) is constructed and the support dismantling conditions required by the enclosure design are met, the anchoring devices (13) are unscrewed at intervals, the foundation pit deformation monitoring is carried out immediately, the threaded piles (3) are dismantled and recycled if the data are stable, and reinforcement measures are adopted for the foundation pit to guarantee the safety of the foundation pit if the data are unstable.

8. The construction method of an inclined support threaded pile supporting structure according to claim 7, characterized in that: in the steps 5) and 6), if the foundation pit deformation exceeds the numerical value required by the enclosure design and the specification, the foundation pit deformation is controlled by further screwing the anchoring device (13), and then the foundation pit deformation is controlled without taking a reinforcing measure, and if the foundation pit deformation is not controlled, the reinforcing measure is taken.

9. The construction method of an inclined support threaded pile supporting structure according to claim 7, characterized in that: in the step 7), when the threaded piles (3) are dismantled, the threaded piles are dismantled and recycled one by one, the first threaded pile section (31) is dismantled from each threaded pile (3), and the second threaded pile section (32) is screwed and recycled after the water stop sleeve (4) is cleaned.

10. The construction method of an inclined support threaded pile supporting structure according to claim 9, characterized in that: the inner wall of the water stop sleeve (4) is provided with a screw plate matched with the screw blade of the screw pile (3), and the interior of the water stop sleeve (4) is sealed by concrete after the screw pile (3) is recovered.

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