Static breaking method and device for pile head of cast-in-place pile

Abstract

The invention relates to the technical field of concrete pile head breaking, and discloses a cast-in-place pile head static breaking method and device, and the cast-in-place pile head static breaking method comprises the following steps: S1, before concrete is poured, the top of a main reinforcement is sleeved with a protective layer sleeve; s2, a bracket is installed at the bottom end of the protective layer sleeve and welded to the reinforcement cage, and a pouring hole is formed in the center of the bracket; s2, one end of a grouting pipe extends into the reinforcement cage and is annularly arranged on the bracket, then the grouting pipe gradually and spirally ascends in a surrounding mode along the periphery of the reinforcement cage, and the two ends of the grouting pipe are both arranged outside the pile top; s3, concrete is poured into the pile hole from the top of the reinforcement cage through the pouring hole; s4, the static crushing agent and water are mixed and stirred according to the proportion of 3: 1; and S5, the prepared grout is injected from one end of the grouting pipe through a grouting machine, grouting is stopped after the grout overflows from the other end of the grouting pipe, the two ends of the grouting pipe are blocked, and the pile head is broken after the grout expands and reacts. The construction method is high in construction efficiency, free of noise and pollution and low in cost.

Description

Technical Field

[0001] The invention relates to the technical field of concrete pile head breaking, in particular to a static breaking method for a cast-in-place pile head and a breaking device thereof. Background Art

[0002] In modern construction projects, highway projects, railway projects and other construction fields, concrete cast-in-place piles are an important part of foundation engineering, and the treatment of their pile heads has always been a key step in the construction process. The traditional method of breaking pile heads mainly relies on manual chiseling, which is not only labor-intensive and slow in construction speed, but also has a great impact on the surrounding environment due to the noise and vibration generated during the operation. In addition, the high cost and low efficiency of manual chiseling also seriously restrict the construction progress and increase the overall construction cost. Therefore, a new type of pile head breaking technology is urgently needed to improve construction efficiency, reduce labor intensity, and reduce the impact on the environment. Summary of the invention

[0003] The purpose of the invention is to design a static breaking device and breaking method for cast-in-place pile heads which has high construction efficiency and is noise-free, pollution-free and low-cost.

[0004] In order to achieve the above object, the present invention provides a method for statically breaking a cast-in-place pile head, which is characterized by comprising the following steps:

[0005] S1 Before pouring concrete, a protective layer is placed on the top of the main reinforcement of the steel cage. The length of the protective layer in the vertical direction is the length of the pile head that needs to be broken;

[0006] S2: a bracket is installed at the bottom end of the protective layer sleeve and welded to the steel cage. A pouring hole for pouring concrete is provided at the center of the bracket;

[0007] S2: one end of the grouting pipe is extended into the steel cage and arranged in a ring on the bracket, and then gradually spirals up along the outer circumference of the steel cage, and both ends of the grouting pipe are placed outside the pile top;

[0008] S3 pours concrete into the pile hole through the pouring hole from the top of the steel cage;

[0009] S4: mixing the static crushing agent and water in a ratio of 3:1 to prepare a crushing slurry;

[0010] S5: inject the prepared slurry from one end of the grouting pipe using a grouting machine, stop grouting after the slurry overflows from the other end of the grouting pipe, seal both ends of the grouting pipe, and wait for the slurry to expand and break the pile head;

[0011] S6 excavates the soil around the pile head and cleans up the broken concrete debris.

[0012] Furthermore, the protective layer is a hose, and the upper and lower ends of the hose are sealed and connected to the main ribs through adhesive tape; or

[0013] The protective layer sleeve is formed by wrapping the main reinforcement with adhesive tape.

[0014] Furthermore, before the S5 operation, clean water is injected into the grouting pipe to flush the pipe.

[0015] Furthermore, the portion of the grouting pipe disposed on the tray is defined as a horizontal wrapping section, and the portion disposed outside the steel cage is defined as a spiral ascending section, and the port of the grouting pipe at one end close to the spiral ascending section is defined as a grouting port, and the port at one end close to the horizontal wrapping section is defined as an overflow port; in S5, a grouting machine is used to inject slurry into the grouting port until the slurry overflows from the overflow hole and stops.

[0016] Furthermore, a spring support frame is provided inside the grouting pipe, and the pipe wall is formed by wrapping non-woven fabric and nylon mesh wire.

[0017] Furthermore, after S2, ports at both ends of the grouting pipe are blocked for standby use and are used for protection during the process of pouring concrete in S3.

[0018] The present invention also provides a static breaking device for a cast-in-place pile head, which is used in the above-mentioned static breaking method for a cast-in-place pile head, and comprises: a steel cage, a grouting pipe, a bracket and a protective layer sleeve;

[0019] The steel cage includes a reinforcing hoop arranged in a transverse annular shape and a plurality of main bars extending in a vertical direction, wherein the plurality of main bars are respectively connected to the reinforcing hoop and are sequentially spaced along the circumference of the reinforcing hoop, and the portions of the plurality of main bars protruding downward from the reinforcing hoop enclose a forming area for pouring concrete to form a cast-in-place pile, and the portions of the plurality of main bars protruding upward from the reinforcing hoop are respectively sleeved with the protective layer sleeves, and enclose a breaking area to be broken after pouring; the bracket is transversely arranged in the reinforcing hoop and connected to the steel cage, and a pouring hole connecting the breaking area and the forming area is opened on the bracket;

[0020] Both ends of the grouting pipe are protruding from the top of the steel cage. The grouting pipe also includes a horizontal surrounding section and a spiral ascending section which are sequentially connected to the two ends. The spiral ascending section is spirally arranged in the breaking area, and the horizontal surrounding section is laid on the bracket in a winding shape.

[0021] Furthermore, the inner diameter of the grouting pipe is 20-40 mm, and the spacing distance L between two adjacent spiral ascending sections in the vertical direction is 10-30 mm.

[0022] Furthermore, the bracket includes a connecting rod, a support rod, a first annular frame and a second annular frame; the first annular frame, the second annular frame and the stiffening hoop are coaxially arranged in sequence from the inside to the outside, the connecting rod extends along the radial direction of the stiffening hoop and is respectively connected to the first annular frame, the second annular frame and the stiffening hoop, the support rod connects the main reinforcement and the first annular frame, and the angle formed between the support rod and the main reinforcement is an acute angle; the injection hole is defined in the middle of the first annular frame.

[0023] Furthermore, the steel cage also includes at least two hanging bars, which are connected to the main bars and protrude upward from the top of the main bars, and the two ends of the grouting pipe are respectively arranged on the two hanging bars in a one-to-one correspondence.

[0024] Compared with the prior art, the static breaking method and breaking device of the cast-in-place pile head according to the embodiment of the present invention have the following beneficial effects:

[0025] The static breaking method and breaking device of the bored pile head of the embodiment of the present invention adopt a static crushing agent, which avoids the impact and vibration of traditional mechanical breaking, protects the pile body structure, and reduces the impact on the surrounding environment; and the grouting pipe adopts a full-section pre-buried form to ensure that the crushing agent acts evenly and achieves complete separation of the pile head and the bored pile, which is convenient for subsequent cleaning and lifting, improves the overall breaking efficiency, saves labor costs, and produces static blasting in the soil body safely and reliably. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 1 is a schematic structural diagram of S1 in the static breaking method of the cast-in-place pile head according to an embodiment of the present invention;

[0027] Figure 2 1 is a schematic structural diagram of S2 in the static breaking device for the cast-in-place pile head according to an embodiment of the present invention;

[0028] Figure 3 Schematic diagram of the structure of S3 in the static breaking device for the cast-in-place pile head according to the embodiment of the present invention

[0029] Figure 4 2 is a schematic structural diagram of a static breaking device for a cast-in-place pile head according to an embodiment of the present invention;

[0030] Figure 5 yes Figure 4 Sectional view in the AA direction;

[0031] Figure 6 2 is a schematic diagram of the structure of the static breaking device for the cast-in-place pile head after pouring concrete according to an embodiment of the present invention;

[0032] Figure 7 yes Figure 6 Cross-sectional view along the BB direction.

[0033] In the figure, 1, steel cage; 11, main reinforcement; 12, stiffening hoop; 13, forming area; 14, breaking area; 15, suspension bar; 2, protective layer sleeve; 3, bracket; 30, grouting hole; 31, first annular frame; 32, second annular frame; 33, connecting rod; 34, supporting rod; 4, grouting pipe; 41, horizontal surrounding section; 42, spiral rising section; 43, grouting port; 44, overflow port; x, vertical direction. DETAILED DESCRIPTION

[0034] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0035] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" used in the present invention to indicate the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0036] In the description of the present invention, it should be understood that the terms "connected", "connected", "fixed" and the like used in the present invention should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or a welding connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] The present invention uses the terms "first", "second", etc. to describe various information, but these information should not be limited to these terms, and these terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, "first" information may also be referred to as "second" information, and similarly, "second" information may also be referred to as "first" information.

[0038] Reference Figure 1 , Figure 2 and Figure 3 A static breaking method and breaking device for a bored pile head according to an embodiment of the present invention comprises the following steps:

[0039] S1 Before pouring concrete, a protective layer sleeve 2 is set on the top of the main reinforcement 11 of the steel cage 1. The length of the protective layer sleeve 2 in the vertical direction x is the length of the pile head of the part to be broken, so as to isolate the main reinforcement 11 of this part from the concrete, which is convenient for the later concrete breaking. Specifically, multiple protective layer sleeves 2 can be set one by one on the top of multiple main reinforcements 11 of the steel cage 1 to the position of the pile top elevation.

[0040] S2 installs a bracket 3 at the bottom end of the protective layer sleeve 2, and welds the bracket 3 to the main reinforcement 11 of the steel cage 1. A pouring hole 30 for pouring concrete is provided at the center of the bracket 3, and the pouring hole 30 is provided to reserve a working space for pouring concrete through the conduit; specifically, the steel cage 1 is provided with a reinforcing hoop 12 at the pile top elevation, and the bracket 3 is arranged in the reinforcing hoop 12, and is respectively welded to the reinforcing hoop 12 and the main reinforcement 11.

[0041] S2 makes one end of the grouting pipe 4 extend into the steel cage 1 and be arranged in a ring on the bracket 3, and then gradually spirally rise along the outer circumference of the steel cage 1, and both ends of the grouting pipe 4 are placed outside the pile top to prevent mud and cement slurry from entering the grouting pipe 4 during concrete pouring and causing blockage, affecting the later grouting effect. The grouting pipe 4 uses the support of the bracket 3 to cover the entire cross section of the cast-in-place pile, forming a full-section pre-embedded form.

[0042] S3 uses a conduit to pour concrete into the pile hole from the top of the steel cage 1 through the pouring hole 30 to form a cast-in-place pile.

[0043] S4: mixing and stirring the static crushing agent and water in a ratio of 3:1 to prepare a breaking slurry. Specifically, the breaking slurry is mixed and used immediately, and the ambient temperature during use is controlled at 0°C to 35°C; the pouring process is completed within 10 to 20 minutes.

[0044] S5 uses a grouting machine to inject the prepared slurry from one end of the grouting pipe 4, stops grouting after the slurry overflows from the other end of the grouting pipe 4, seals both ends of the grouting pipe 4, and waits for the slurry to expand and react to break the pile head. The broken slurry reacts fully, generates horizontal and vertical expansion pressures around, and breaks the grouting pipe 4 and the concrete around it, achieving static and silent crushing of the pile head.

[0045] S6 excavates the soil around the pile head and cleans the broken concrete debris. After the crushing, the part of the pile head to be broken is completely separated from the cast-in-place pile. After the soil around the pile head is excavated and the concrete debris is cleaned, a crane is used to lift the remaining part of the pile head in the steel cage 1 to complete the static breaking of the pile head.

[0046] In some improved solutions of the present application, the protective layer sleeve 2 is a hose, and the upper and lower ends of the hose are sealed and connected to the main reinforcement 11 by tape. Specifically, a hose with an inner diameter 2 to 3 mm larger than the outer diameter of the main reinforcement 11 can be used as the protective layer sleeve 2, and the upper and lower ends of the hose are sealed with tape to prevent concrete from entering. If there is an acoustic detection pipe or a grouting pipe, the same method can be used for isolation.

[0047] In some other improved solutions of the present application, the protective layer sleeve 2 is formed by wrapping the main reinforcement 11 with adhesive tape, which can also form an isolation effect.

[0048] In some improved solutions of the present application, clean water is injected into the grouting pipe 4 before the S5 operation to flush the pipe, remove foreign matter in the grouting pipe 4 to avoid blockage, and ensure the effect of breaking the subsequent grouting expansion.

[0049] In some improved schemes of the present application, the portion of the grouting pipe 4 disposed on the tray is defined as a horizontal surrounding section 41, and the portion disposed outside the steel cage 1 is defined as a spiral ascending section 42, and the port of the grouting pipe 4 close to one end of the spiral ascending section 42 is defined as a grouting port 43, and the port close to one end of the horizontal surrounding section 41 is defined as an overflow port 44; in the S5, a grouting machine is used to inject slurry into the grouting port 43 until the overflow hole overflows the slurry and stops. During grouting, the broken slurry first enters the spiral ascending section 42, and the spiral ascending section 42 is quickly filled by gravity, and then the horizontal surrounding section 41 is filled in sequence and overflows from the overflow port 44.

[0050] In some improved schemes of the present application, the interior of the grouting pipe 4 is hollow and provided with a rigid spring support frame, and its pipe wall is formed by wrapping non-woven fabric and nylon mesh to resist the concrete pressure, so that the grouting pipe 4 maintains structural stability during the concrete pouring process and will not deform, thereby avoiding affecting the subsequent grouting effect.

[0051] In some improved solutions of the present application, the ports at both ends of the grouting pipe 4 are blocked for standby after S2 and are used for protection during the process of pouring concrete in S3 to prevent debris from entering the grouting pipe 4.

[0052] Reference Figures 4 to 7 The preferred embodiment of the present invention is a static breaking device for a bored pile head, which is used in the above-mentioned static breaking method for a bored pile head, comprising: a steel cage 1, a grouting pipe 4, a bracket 3 and a protective layer sleeve 2;

[0053] The steel cage 1 comprises a reinforcing hoop 12 arranged in a transverse annular shape and a plurality of main bars 11 extending in a vertical direction x, wherein the plurality of main bars 11 are respectively connected to the reinforcing hoop 12 and are sequentially arranged at intervals along the circumference of the reinforcing hoop 12, and the portions of the plurality of main bars 11 protruding downward from the reinforcing hoop 12 enclose a forming area 13 for pouring concrete to form a cast-in-place pile, and the portions of the plurality of main bars 11 protruding upward from the reinforcing hoop 12 are respectively sleeved with the protective layer sleeve 2, and enclose a breaking area 14 to be broken after pouring; the bracket 3 is transversely arranged in the reinforcing hoop 12 and connected to the steel cage 1, and a pouring hole 30 connecting the breaking area 14 and the forming area 13 is opened at the center of the bracket 3;

[0054] Both ends of the grouting pipe 4 are protruding from the top of the steel cage 1. The grouting pipe 4 also includes a horizontal surrounding section 41 and a spiral ascending section 42 which are connected to the two ends in sequence. The spiral ascending section 42 is spirally arranged in the breaking area 14, and the horizontal surrounding section 41 is laid on the bracket 3 in a winding shape.

[0055] The grouting pipe 4 is arranged in sections, and the spiral ascending section 42 is used to make the breaking process more uniform, and the horizontal surrounding section 41 is used to completely separate the pile head from the top of the cast-in-place pile, so that the pile head can be broken quickly and effectively, shortening the construction period.

[0056] In some improved solutions of the present application, the inner diameter of the grouting pipe 4 is 20-40 mm, and the spacing distance L between two adjacent sections of the spiral ascending section 42 in the vertical direction x is 10-30 mm.

[0057] In some improved schemes of the present application, the bracket 3 includes a connecting rod 33, a support rod 34, a first annular frame 31 and a second annular frame 32; the first annular frame 31, the second annular frame 32 and the stiffening hoop 12 are coaxially arranged in sequence from the inside to the outside, the connecting rod 33 extends along the radial direction of the stiffening hoop 12 and is respectively connected to the first annular frame 31, the second annular frame 32 and the stiffening hoop 12, the support rod 34 connects the main reinforcement 11 and the first annular frame 31, and the angle formed between the support rod 34 and the main reinforcement 11 is an acute angle; the middle of the first annular frame 31 defines the injection hole 30.

[0058] The bracket 3 is connected by relying on the original structural design of the steel cage 1. Specifically, the bracket 3 can also be provided with a third ring frame, a fourth ring frame, etc. between the second ring frame 32 and the reinforcing hoop 12 as needed. The grouting pipe 4 is wound along the ring frame in sequence, and the ring frame provides support for the grouting pipe 4 to prevent it from falling to the lower forming area 13. The support rod 34, the main reinforcement 11 and the first ring frame 31 and the second ring frame 32 can be welded to ensure a firm and reliable connection.

[0059] In some improved solutions of the present application, the steel cage 1 further includes at least two hanging bars 15, which are connected to the main bars 11 and protrude upward from the top of the main bars 11, and the two ends of the grouting pipe 4 are respectively and one-to-one arranged on the two hanging bars 15. The hanging bars 15 are used to ensure that the two ends of the grouting pipe 4 protrude from the steel cage 1 and extend out of the ground, so as to prevent debris from entering the grouting pipe 4.

[0060] In summary, the embodiments of the present invention provide a static breaking method and breaking device for a bored pile head, which have the following advantages:

[0061] 1) The expansion pipe is replaced by the grouting pipe 4 and the grouting ports 43 and the overflow ports 44 at both ends are reserved above the ground, so as to avoid mud and cement slurry entering the pipe during the concrete pouring process to cause blockage and affect the grouting effect in the later stage.

[0062] 2) Using one grouting pipe 4 to replace multiple expansion pipes reduces the number of grouting times, and the pipeline can be flushed through the grouting port 43 in the later stage to avoid pipeline blockage and failure.

[0063] 3) The grouting pipe 4 is pre-buried in full section, and a rigid spring is used as a support frame inside the grouting pipe 4. The outer wall is formed by wrapping non-woven fabric and nylon wire mesh, which can resist the concrete pressure and will not deform during the concrete pouring process.

[0064] 4) Considering the working space of the conduit during concrete pouring, a pouring hole 30 is opened on the bracket 3, and the grouting pipe 4 is horizontally wound on the bracket 3.

[0065] 5) The pile head can be broken before foundation pit excavation, which improves construction safety, eliminates potential safety hazards caused by blasting, saves construction time and improves work efficiency.

[0066] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A static breaking method for a cast-in-place pile head, characterized in that: The following steps are involved: S1 Before pouring concrete, a protective layer is placed on the top of the main reinforcement of the steel cage. The length of the protective layer in the vertical direction is the length of the pile head that needs to be broken; S2: a bracket is installed at the bottom end of the protective layer sleeve and welded to the steel cage. A pouring hole for pouring concrete is provided at the center of the bracket; S2: one end of the grouting pipe is extended into the steel cage and arranged in a ring on the bracket, and then gradually spirals up along the outer circumference of the steel cage, and both ends of the grouting pipe are placed outside the pile top; S3 pours concrete into the pile hole through the pouring hole from the top of the steel cage; S4: mixing the static crushing agent and water in a ratio of 3:1 to prepare a crushing slurry; S5: inject the prepared slurry from one end of the grouting pipe using a grouting machine, stop grouting after the slurry overflows from the other end of the grouting pipe, seal both ends of the grouting pipe, and wait for the slurry to expand and break the pile head; S6 excavates the soil around the pile head and cleans up the broken concrete debris.

2. The static breaking method of the cast-in-place pile head according to claim 1, characterized in that: The protective layer sleeve is a hose, and the upper and lower ends of the hose are sealed and connected to the main reinforcement through adhesive tape; or The protective layer sleeve is formed by wrapping the main reinforcement with adhesive tape.

3. The static breaking method of the cast-in-place pile head according to claim 1, characterized in that: Before the operation of S5, clean water is injected into the grouting pipe to flush the pipe.

4. The static breaking method of the cast-in-place pile head according to claim 1, characterized in that: The portion of the grouting pipe disposed on the tray is defined as a horizontal wrapping section, and the portion disposed outside the steel cage is defined as a spiral ascending section. The port of the grouting pipe close to one end of the spiral ascending section is defined as a grouting port, and the port close to one end of the horizontal wrapping section is defined as an overflow port. In S5, a grouting machine is used to inject slurry into the grouting port until the slurry overflows from the overflow hole and stops.

5. The static breaking method of the cast-in-place pile head according to claim 1, characterized in that: The grouting pipe is provided with a spring support frame inside, and the pipe wall is formed by wrapping non-woven fabric and nylon mesh wire.

6. The static breaking method of the cast-in-place pile head according to claim 1, characterized in that: After S2, the ports at both ends of the grouting pipe are blocked for standby use and are used for protection during the concrete pouring process in S3.

7. A static breaking device for a cast-in-place pile head, used in the static breaking method for a cast-in-place pile head as claimed in any one of claims 1 to 6, characterized in that: include: Steel cage, grouting pipe, bracket and protective cover; The steel cage includes a reinforcing hoop arranged in a transverse annular shape and a plurality of main bars extending in a vertical direction, wherein the plurality of main bars are respectively connected to the reinforcing hoop and are sequentially spaced along the circumference of the reinforcing hoop, and the portions of the plurality of main bars protruding downward from the reinforcing hoop enclose a forming area for pouring concrete to form a cast-in-place pile, and the portions of the plurality of main bars protruding upward from the reinforcing hoop are respectively sleeved with the protective layer sleeves, and enclose a breaking area to be broken after pouring; the bracket is transversely arranged in the reinforcing hoop and connected to the steel cage, and a pouring hole connecting the breaking area and the forming area is opened on the bracket; Both ends of the grouting pipe are protruding from the top of the steel cage. The grouting pipe also includes a horizontal surrounding section and a spiral ascending section which are sequentially connected to the two ends. The spiral ascending section is spirally arranged in the breaking area, and the horizontal surrounding section is laid on the bracket in a winding shape.

8. The static breaking device for the cast-in-place pile head according to claim 7, characterized in that: The inner diameter of the grouting pipe is 20-40 mm, and the spacing distance L between two adjacent sections of the spiral ascending section in the vertical direction is 10-30 mm.

9. The static breaking device for the cast-in-place pile head according to claim 7, characterized in that: The bracket includes a connecting rod, a supporting rod, a first annular frame and a second annular frame; the first annular frame, the second annular frame and the stiffening hoop are coaxially arranged in sequence from the inside to the outside, the connecting rod extends along the radial direction of the stiffening hoop and is respectively connected to the first annular frame, the second annular frame and the stiffening hoop, the supporting rod connects the main reinforcement and the first annular frame, and the angle formed between the supporting rod and the main reinforcement is an acute angle; the injection hole is defined in the middle of the first annular frame.

10. The static breaking method of the cast-in-place pile head according to claim 7, characterized in that: The steel cage also includes at least two hanging bars, which are connected to the main bars and protrude upward from the top of the main bars. The two ends of the grouting pipe are respectively and one by one arranged on the two hanging bars.

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