Anti-floating pile and method for forming the same

Abstract

The application discloses an anti-floating pile and a pile forming method thereof, and relates to the technical field of building construction, aiming at making the anti-floating anchor rod of the anti-floating pile located at or as far as possible at the center of a pile hole. The technical scheme adopted by the application is as follows: the anti-floating pile forming method is used to firstly determine the position of the pile hole, form the pile hole through a drilling machine, clean the pile hole, and lay a bottom cushion layer at the bottom of the pile hole; then, the anti-floating anchor rod with a positioning structure is made, the anti-floating anchor rod is hoisted and inserted into the pile hole together with a grouting pipe; finally, fine aggregate is filled into the pile hole, grouting is carried out through the grouting pipe, and maintenance is carried out after the grouting is completed. The positioning structure comprises a support seat, a clamping groove is arranged at one end of the support seat, a main reinforcement is located in the clamping groove, a connecting belt is connected or arranged at the other end of the support seat, and the support seat forms a ring structure through the connecting belt. The support seat plays a role in limiting the distance between the main reinforcement and the hole wall from various directions, so that the anti-floating anchor rod is located at or as far as possible at the center of the pile hole. The application is used for the design and construction of the anti-floating pile.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, specifically to an anti-buoyancy pile that can position the anti-buoyancy anchor at the center of the pile hole and a method for pile formation thereof. Background Technology

[0002] An anti-buoyancy pile is a structure designed to resist upward displacement of a building. The general method for constructing an anti-buoyancy pile involves binding a certain number of steel bars to form anti-buoyancy anchors, inserting these anchors into a pile hole, filling the hole with fine aggregate, and then injecting concrete grout to form the anti-buoyancy pile. The portion of the anchor outside the pile hole is then bent away from the hole to form an anchoring claw. Concrete is then poured at the top of the pile hole to form the underground structure. The anchoring claw is located within the concrete, connecting the anti-buoyancy pile to the underground structure, thus giving the underground structure its anti-buoyancy capability.

[0003] Anti-buoyancy anchors are prone to displacement after being inserted into the pile hole, meaning their centerline does not coincide with the centerline of the pile hole. This misalignment leads to inconsistent concrete cover thickness, reducing the bond between the anchor and the concrete and thus diminishing its anchoring effectiveness. Disruption of the anchoring balance system directly impacts the anti-buoyancy capacity of the underground structure, posing a safety hazard. Summary of the Invention

[0004] The present invention first provides a method for forming anti-buoyancy piles, the purpose of which is to place the anti-buoyancy anchor rod of the anti-buoyancy pile at or as far as possible at the center of the pile hole.

[0005] The technical solution adopted in this invention is: a method for constructing anti-buoyancy piles, comprising the following steps:

[0006] S1. Determine the location of the pile hole and form the pile hole using a drilling rig.

[0007] S2. Clean the pile hole, and then lay a layer of coarse aggregate at the bottom of the pile hole as a base layer. The base layer is used to ensure the protective layer thickness between the lower end of the anti-buoyancy anchor and the bottom of the pile hole. The coarse aggregate is generally pebbles or crushed stone.

[0008] S3. Fabricate an anti-buoyancy anchor rod with a positioning structure, and hoist the anti-buoyancy anchor rod together with the grouting pipe and insert it into the pile hole, including the following steps S3.1 to S3.3.

[0009] S3.1 At least three main reinforcing bars are fixedly connected to at least two steel rings, with each main reinforcing bar parallel to the others and distributed around the outer periphery of the steel rings, and the steel rings are spaced apart along the length of the main reinforcing bars.

[0010] To balance the stress on each main reinforcement bar, the following further measures are taken: any two adjacent main reinforcement bars form a central angle with the center of the steel ring, and the main reinforcement bars are welded to the steel ring.

[0011] S3.2 At least two rings of positioning structures are installed on the outside of the main reinforcement bars. Each ring of positioning structures is arranged at intervals along the length of the main reinforcement bars. Each ring of positioning structures includes a number of support seats that are the same as the number of main reinforcement bars. One end of the support seat is provided with a slot, and the main reinforcement bars are located in the slot. The other end of the support seat is connected to or provided with two connecting strips. The support seats are arranged radially along the steel ring or parallel to the radial direction of the steel ring. The connecting strips of adjacent support seats are connected to each other or are a whole, forming a ring structure.

[0012] To enable the positioning structure to adapt to pile holes of different diameters, the support base further includes a support part and a slot part. The support part is connected to or equipped with two connecting bands, and the slot part is equipped with a slot. The support part and the slot part are connected by a screw. At least one of the support part and the slot part is threadedly engaged with the screw. The screw is arranged radially along the steel ring or parallel to the radial direction of the steel ring.

[0013] For ease of construction, the connecting straps should ideally be connected on-site. Furthermore, two adjacent supports within the same positioning structure should form a group of supports, and at least two connecting straps between these groups should each have a mutually compatible connecting structure. For example, the connecting structure could be: one connecting strap with a one-way ratchet, and the other with a locking mechanism that matches the one-way ratchet.

[0014] To reduce the friction between the support base and the borehole wall, and thus reduce the resistance to inserting the anti-buoyancy anchor into the borehole, the support base is further designed with a spherical cap shape at the end furthest from the slot. For example, the end of the support base furthest from the slot is hemispherical.

[0015] S3.3 Grouting pipes are inserted into each steel ring, and the grouting pipes are tied and fixed to the main reinforcement.

[0016] To facilitate grouting operations and prevent blockage at the lower end of the grouting pipe outlet, the upper end of the grouting pipe is longer than the upper end of the main reinforcement bar, and the lower end of the grouting pipe is shorter than the lower end of the main reinforcement bar. For example, if the grouting pipe is a PVC pipe with a wall thickness greater than 1.0 mm, the upper end of the grouting pipe is 400 mm longer than the upper end of the main reinforcement bar, and the lower end of the grouting pipe is 400 mm shorter than the lower end of the main reinforcement bar.

[0017] S4. Fill the pile hole with coarse aggregate and grout through the grouting pipe. After grouting, cure the material. The coarse aggregate is generally pebbles or crushed stone.

[0018] The present invention also provides an anti-buoyancy pile, which is constructed according to the above-described anti-buoyancy pile construction method.

[0019] The beneficial effects of the anti-buoyancy pile and its pile formation method of this invention are as follows: Each main reinforcement bar is fixed to the outer circumference of the steel ring, and all the main reinforcement bars and all the steel rings form a whole, achieving relative fixation between the main reinforcement bars. At least two rings of positioning structures are provided on the outer side of the main reinforcement bars. After the whole structure formed by the main reinforcement bars, steel rings, support seats, and grouting pipes is inserted into the pile hole, the end of each support seat away from the slot contacts the hole wall, supporting the main reinforcement bars from all directions. This controls the distance between the main reinforcement bars and the hole wall, ensuring that the anti-buoyancy anchor is located, or as close as possible, to the center of the pile hole. The distance between the support part and the slot part of the support seat can be adjusted by a screw, that is, the effective support height of the support seat can be adjusted, thereby adapting to pile holes of different diameters and improving versatility. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of an embodiment of the anti-buoyancy anchor rod with a positioning structure in this invention.

[0021] Figure 2 yes Figure 1 A schematic diagram of one embodiment of the support base and connecting belt.

[0022] Figure 3 yes Figure 1 A schematic diagram of another embodiment of the support base and connecting belt.

[0023] Figure 4 This is a schematic diagram of another embodiment of the anti-buoyancy anchor rod with a positioning structure in this invention.

[0024] Figure 5 yes Figure 4 A schematic diagram of one embodiment of the support base and connecting belt.

[0025] Figure 6 yes Figure 4 A schematic diagram of another embodiment of the support base and connecting belt.

[0026] Reference numerals: 1. Main rib; 2. Steel ring; 3. Support seat; 31. Support part; 32. Slot part; 33. Screw; 4. Connecting strip; 41. One-way ratchet; 42. Locking buckle. Detailed Implementation

[0027] The invention will now be further described with reference to the accompanying drawings.

[0028] The present invention provides a method for constructing anti-buoyancy piles, which involves constructing anti-buoyancy piles at the bottom of a foundation pit, and includes the following steps.

[0029] S1. Determine the location of the pile hole and form the pile hole using a drilling rig.

[0030] Before determining the location of the pile holes, the axis of the proposed underground structure can be laid out first. The pile hole locations are then determined according to the control points of each axis after verification. A double-control method can be used to ensure that the pile hole location error does not exceed 50mm. After the drilling rig is in place, a 3-4m long core tube is used to ensure the straightness of the drilling rig. The drilling speed depends on the rock quality, generally 30-40cm / min is appropriate. Each time drilling begins, the drill bit diameter, wear level, and steering mechanism should be checked; severely worn parts should be repaired promptly. When drilling begins, the guide tube should be straightened to maintain the borehole's verticality, and the soil and rock mass inside the hole should be removed as the drilling progresses. The three processes of hole formation, soil and rock removal, and casing follow-up are repeated to complete the formation of one pile hole. The depth of the pile hole should be at least 200mm greater than the length of the anti-buoyancy anchor.

[0031] S2. Clean the pile hole, and then lay a layer of coarse aggregate at the bottom of the pile hole as a base layer. The base layer is used to ensure the protective layer thickness between the lower end of the anti-buoyancy anchor and the bottom of the pile hole. The coarse aggregate is generally pebbles or crushed stone.

[0032] After drilling to the designed depth, the loose soil and stones in the pile hole are cleaned to ensure that the hole does not collapse. Then, a layer of coarse aggregate, which is pebbles or crushed stone, is laid at the bottom of the pile hole as a base layer. The base layer becomes a protective layer after subsequent grouting to ensure that the lower end of the anti-buoyancy anchor does not contact the rock and soil at the bottom of the pile hole. The thickness of the base layer is generally about 20cm.

[0033] S3. Fabricate anti-buoyancy anchors with positioning structures, and hoist the anti-buoyancy anchors together with the grouting pipes and insert them into the pile hole. See [link / reference] Figures 1-6 This includes the following steps S3.1 to S3.3.

[0034] S3.1 At least three main reinforcing bars 1 are fixedly connected to at least two steel rings 2, with each main reinforcing bar 1 parallel to each other and distributed on the outer periphery of the steel rings 2, and the steel rings 2 are arranged at intervals along the length direction of the main reinforcing bars 1.

[0035] The main reinforcement bar 1 is generally a threaded steel bar, and it is fixedly connected to the steel ring 2, making each main reinforcement bar 1 and the steel ring 2 a whole anti-buoyancy anchor. For example, the main reinforcement bar 1 and the steel ring 2 are welded together. There are at least two steel rings 2 to ensure the stability of the main reinforcement bar 1 and the steel ring 2 as a whole. The steel rings 2 are arranged at intervals along the length of the main reinforcement bar 1, and are generally evenly spaced. The plane corresponding to the steel ring 2 is perpendicular to the straight line corresponding to the main reinforcement bar 1. In order to balance the force on each main reinforcement bar 1, the main reinforcement bars 1 are evenly distributed on the outer perimeter of the steel ring 2, that is, the central angle between any two adjacent main reinforcement bars 1 and the center of the steel ring 2 is equal.

[0036] S3.2 Install a positioning structure on the outside of the main reinforcement 1.

[0037] At least two rings of positioning structures are provided on the outer side of the main reinforcement 1. These positioning structures support the borehole wall, ensuring that each main reinforcement 1 is located, or as close as possible, to the center of the borehole at the location of the positioning structure. The positioning structures are spaced apart along the length of the main reinforcement 1, ensuring that the main reinforcement 1 is located, or as close as possible, to the center of the borehole at different depths. Each ring of positioning structures includes support seats 3, the number of which matches the number of main reinforcement 1. Each support seat 3 corresponds one-to-one with each main reinforcement 1. The support seats 3 are arranged radially along or parallel to the steel ring 2; that is, the positioning structures and steel ring 2 can be arranged in a one-to-one correspondence or staggered arrangement. One end of each support seat 3 has a groove, within which the main reinforcement 1 is located. The groove only needs to accommodate the main reinforcement 1, and its cross-section is generally semi-circular. The other end of each support seat 3 is connected to or has two connecting straps 4. The connecting straps 4 and the support seat 3 can be a single unit, or the connecting straps 4 can be detachably or non-detachably connected to the support seat 3. For the same ring positioning structure, the connecting strips 4 of adjacent support seats 3 are connected to each other or are a whole, forming a ring structure.

[0038] Support 3 can be a structural component with a fixed support height, such as... Figures 1-3 As shown. To allow the positioning structure to adapt to pile holes of different diameters, the support height of support base 3 is adjustable. See also... Figures 4-6 For a single support base 3, the support base 3 includes a support portion 31 and a slot portion 32, which are connected by a screw 33. The support portion 31 connects two connecting straps 4. The two connecting straps 4 can be independent and connected to the support portion 31 separately, or they can be integrated as a whole and fixed or connected to the support portion 31. The slot portion 32 has a slot, and the main reinforcing bar 1 is located within the slot. The connection between the support portion 31 and the slot portion 32 by the screw 33 is intended to adjust the effective support height of the support base to accommodate pile holes of different diameters. At least one of the support portion 31 and the slot portion 32 is threadedly engaged with the screw 33. The support portion 31 and the slot portion 32 can each have a screw hole, with both ends of the screw 33 threadedly engaged with the screw holes in the support portion 31 and the slot portion 32, respectively; alternatively, either the support portion 31 or the slot portion 32 has a screw hole, while the other is integrated or fixedly connected to the screw 33. The screw 33 is arranged radially along the steel ring 2. In this case, the positioning structure is arranged in a one-to-one correspondence with the steel ring 2. Alternatively, the screw 33 is parallel to the radial direction of the steel ring 2. In this case, the positioning structure is arranged in a staggered manner with the steel ring 2 to ensure that the effective support height of the support seat 3 can be effectively adjusted through the screw 33.

[0039] For the same ring positioning structure, the connecting strips 4 of adjacent support seats 3 are interconnected or formed as a whole, forming a ring structure. The connecting strips 4 are used to connect the various support seats 3 into a ring. For the same support seat 3, the two connecting strips 4 connecting the support seat 3 can be independent and connected to the support seat 3 separately, or the two connecting strips 4 can be a whole and fixed or connected to the support seat 3. When the connecting strips 4 are made of elastic material, each segment of the connecting strips 4 in the same ring positioning structure can be a whole, that is, there are no joints in the connecting strips 4 in each ring positioning structure. The connecting strips 4 of adjacent support seats 3 can also be connected on-site during construction, that is, there is at least one joint in the connecting strips 4 in each ring positioning structure. In this case, two adjacent support seats 3 located in the same positioning structure form a group of support seats 3, and the two connecting strips 4 between at least one group of support seats 3 are respectively provided with mutually compatible connecting structures. To achieve rapid connection between the connecting straps 4 and maintain a stable connection, the connection structure consists of a one-way ratchet 41 on one connecting strap 4 and a latch 42 on the other connecting strap 4 that matches the one-way ratchet 41. The one-way ratchet 41 can only be inserted into the latch 42 and tightened; the one-way ratchet 41 cannot be pulled out of the latch 42. For the same ring positioning structure, the two connecting straps 4 between two adjacent support seats 3 can each be equipped with a mutually matching connection structure. The structure of a single support seat 3 is as follows: Figure 2 and Figure 5 As shown; or, for the same ring positioning structure, only one set of mutually adaptable connection structures is set for three adjacent support seats 3, such as Figure 3 and Figure 6 As shown.

[0040] When the main reinforcement 1, steel ring 2, and positioning structure are inserted into the pile hole as a whole, the end of the support seat 3 away from the slot rubs against the hole wall. To reduce the friction between the support seat 3 and the hole wall, that is, to reduce the resistance of inserting the anti-buoyancy anchor into the pile hole, the end of the support seat 3 away from the slot is spherical. For example, the end of the support seat 3 away from the slot is hemispherical.

[0041] S3.3 Grouting pipes are inserted into each steel ring 2, and the grouting pipes are tied and fixed to the main reinforcement.

[0042] The inner ring of each steel ring 2 is used to insert grouting pipes, and the steel ring 2 serves to fix and protect the grouting pipes. The grouting pipes are inserted into each steel ring 2 and tied to the main reinforcement 1 for fixation. To facilitate grouting operations, the upper end of the grouting pipe is longer than the upper end of the main reinforcement 1, for example, 400mm longer. To prevent the lower end of the grouting pipe from entering the soil layer at the bottom of the pile hole and preventing grout from flowing out, thus affecting the grouting quality, the lower end of the grouting pipe is shorter than the lower end of the main reinforcement 1, for example, 400mm shorter. The grouting pipe can be a 20mm diameter PVC pipe. To prevent the pipe from bursting under grout pressure during grouting, which would affect the grouting effect, the wall thickness of the grouting pipe is greater than 1.0mm.

[0043] S4. Fill the pile hole with coarse aggregate and grout through the grouting pipe. After grouting, cure the material. The coarse aggregate is generally pebbles or crushed stone.

[0044] The coarse aggregate is generally pebbles or crushed stone. After filling to the design elevation, the casing is pulled out, and grouting is then carried out through the grouting pipe. The grouting pressure is generally 0.8–1.0 MPa. If thick grout oozes from the borehole during grouting, grouting should be paused, and pressure should be restored after an interval of about 10 minutes. Grouting should be stopped when thick grout oozes out again. After grouting is completed, curing should be carried out. During the curing period, the exposed anti-buoyancy anchor rods should not be touched by external force. After the curing period, the anti-buoyancy anchor rods should be inspected and accepted promptly.

Claims

1. Anti-float pile piling method, characterized by: The method comprises the following steps: S1, determining the pile hole position, and forming the pile hole through a drilling machine; S2, cleaning the pile hole, and laying a layer of coarse aggregate as a bottom cushion layer at the bottom of the pile hole; S3, manufacturing an anti-floating anchor rod with a positioning structure, and hoisting and inserting the anti-floating anchor rod into the pile hole together with a grouting pipe, comprising the following steps: S3.1, fixedly connecting at least three main reinforcements (1) with at least two steel rings (2), the main reinforcements (1) being parallel to each other and distributed on the outer periphery of the steel rings (2), and the steel rings (2) being arranged at intervals along the length direction of the main reinforcements (1); S3.2, installing at least two circles of positioning structures on the outer side of the main reinforcements (1), each circle of the positioning structures being arranged at intervals along the length direction of the main reinforcements (1), each circle of the positioning structures comprising support seats (3) with a number consistent with that of the main reinforcements (1), the support seat (3) comprising a support part (31) and a clamping groove part (32), the support part (31) and the clamping groove part (32) being connected through a screw rod (33), at least one of the support part (31) and the clamping groove part (32) being threadedly connected with the screw rod (33), the screw rod (33) being arranged along the radial direction of the steel ring (2) or being parallel to the radial direction of the steel ring (2), the clamping groove part (32) at one end of the support seat (3) being provided with a clamping groove, the main reinforcement (1) being located in the clamping groove, the support part (31) at the other end of the support seat (3) being connected with or provided with two connecting belts (4), the support seat (3) being arranged along the radial direction of the steel ring (2) or being parallel to the radial direction of the steel ring (2), the connecting belts (4) of adjacent support seats (3) being connected with each other or being an integral whole, and forming a ring structure; S3.3, threading a grouting pipe in each steel ring (2), and binding and fixing the grouting pipe with the main reinforcement (1); S4, filling the coarse aggregate into the pile hole, grouting through the grouting pipe, and curing after the grouting is completed.

2. The anti-float pile forming method according to claim 1, characterized by: In S2 and S4, the coarse aggregate is pea stone or gravel.

3. The anti-float pile forming method according to claim 1, characterized by: In S3.1, any two adjacent main reinforcements (1) and the center of the steel ring (2) form equal central angles, and the main reinforcement (1) and the steel ring (2) are weldedly connected.

4. The anti-float pile-forming method according to claim 1, wherein: In S3.2, two adjacent support seats (3) in the same circle of the positioning structures are a group of support seats (3), and the two connecting belts (4) between at least one group of support seats (3) are respectively provided with mutually matched connecting structures.

5. The anti-float pile forming method according to claim 4, characterized in that: In S3.2, the connecting structure is that one connecting belt (4) is provided with a one-way ratchet (41), and the other connecting belt (4) is provided with a lock catch (42) matched with the one-way ratchet (41).

6. The anti-float pile forming method according to any one of claims 1 to 5, characterized in that: In S3.2, the end of the support seat (3) away from the clamping groove is in a spherical segment shape.

7. The anti-float pile forming method according to any one of claims 1 to 5, characterized in that: In S3.3, the upper end of the grouting pipe is longer than the upper end of the main reinforcement (1), and the lower end of the grouting pipe is shorter than the lower end of the main reinforcement (1).

8. The anti-float pile-forming method according to claim 7, characterized by: In S3.3, the grouting pipe is a PVC pipe, the thickness of the wall of the PVC pipe is greater than 1.0 mm, the upper end of the grouting pipe is 400 mm longer than the upper end of the main reinforcement (1), and the lower end of the grouting pipe is 400 mm shorter than the lower end of the main reinforcement (1).

9. Anti-floatation pile, characterized in that: The anti-floating pile is obtained by the anti-floating pile forming method according to any one of the preceding claims 1 to 8.

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