Pipe pile grouting expanded head pile forming process special for prestressed concrete water jet cutter and pipe

Abstract

The invention relates to a pipe pile grouting expanded head pile forming process special for a prestressed concrete water jet cutter and a pipe, and belongs to the field of pipe pile construction. The large-head concrete block is integrally connected with the lower end of the tubular pile body and is in an irregular shape, the tubular pile body sequentially comprises a pile cap, a plurality of pipe joints and an inverted-cone-shaped pile head from top to bottom, the tubular pile body is provided with at least one high-pressure water or cement paste channel in the axial direction of the tubular pile body, and the pile head is provided with a material water hole communicated with the high-pressure water or cement paste channel. During construction, even if a special stratum is encountered, the hard stratum is impacted through the high-pressure water jet cutter, and static pressure or hammering is matched, so that the problem that an existing pipe pile is difficult to descend is solved. When the designed elevation is reached, guniting is carried out through high-pressure water or a cement paste channel in the pipe pile body, and a sphere-like expanded head is formed at the bottom of the pipe pile; the bearing capacity of a single pile can be improved, settlement of the pile body is limited, local displacement of the pile body is eliminated, and the anti-floating effect of the pile body is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of vibro-impact construction, in particular to a prestressed concrete water jet special pipe pile grouting enlarged head pile forming process and pipe material. Background Art

[0002] Pipe piles are a kind of foundation engineering component composed of steel pipes and concrete.

[0003] Pipe piles are divided into post-tensioned prestressed pipe piles and pre-tensioned prestressed pipe piles, prestressed concrete pipe piles (PC pipe piles), prestressed concrete thin-walled pipe piles (PTC pipe piles) and high-strength prestressed concrete pipe piles (PHC pipe piles).

[0004] Piles are divided into prestressed concrete pipe piles (PC pipe piles), prestressed concrete thin-walled pipe piles (PTC pipe piles) and prestressed high-strength concrete pipe piles (PHC pipe piles) according to the concrete strength grade and wall thickness. The concrete strength of PC piles shall not be lower than C50 concrete, the strength grade of PTC pipe piles shall not be lower than C60, and the concrete strength grade of PHC piles shall not be lower than C80.

[0005] The existing pipe piles and their construction process have the following problems:

[0006] In case of special strata, it is difficult to lower the pipe pile. Continuous static pressure and hammering will cause the pile end or pile body to break, the joints to crack and deform, and piles to break. The pile foundation will fail the inspection. In case of special geological conditions, it is necessary to equip the drilling equipment and it is difficult to pile.

[0007] The bearing capacity of the bearing layer at the pile end is limited, and the pull-out resistance of the pile body is tested during construction in the same area.

[0008] After the pipe piles are formed and placed for a period of time, they will move up and down.

[0009] During the construction of piles, there is a risk of soil squeezing effect, especially during the construction of pile groups or large pile diameters, which can easily cause the ground to rise or bulge, and the pipe piles on the side to float, break, or shift.

[0010] The present invention can solve the above-mentioned problems, and greatly improve the bearing capacity of a single pipe pile, thus playing a role in protecting the environment of groundwater. Summary of the invention

[0011] In view of the shortcomings of the prior art, the present invention provides a prestressed concrete water jet special pipe pile grouting enlarged head pile forming process and pipe material, and the technical scheme is as follows:

[0012] The prestressed concrete water jet special pipe pile grouting enlarged head pile pipe comprises a pipe pile body, a large-head concrete block integrally connected to the lower end of the pipe pile body and having an irregular shape, the pipe pile body comprises a pile cap, multiple pipe sections, and an inverted cone-shaped pile head from top to bottom, and the pile head is located inside the large-head concrete block; the pipe pile body is provided with at least one high-pressure water or cement slurry channel along its axial direction, and the pile head is provided with a water hole connected to the high-pressure water or cement slurry channel.

[0013] As a further solution of the present invention, the pipe segment includes a reinforced concrete pipe body and a pipe ring integrally connected to the upper and lower ends of the reinforced concrete pipe body, a steel cage is arranged inside the reinforced concrete pipe body, and the steel cage is fixedly connected to the pipe ring; the high-pressure water or cement slurry channel includes a first channel arranged along the axial direction of the pipe segment, and the upper and lower adjacent reinforced concrete pipe bodies, the lower end of the pipe segment and the pile head, and the upper end of the pipe segment and the pile cap are all connected by setting pin pipes.

[0014] As a further solution of the present invention, a sealing gasket is provided on the outer sleeve of the pin tube.

[0015] As a further solution of the present invention, the pipe ring is provided with a first pin hole that is clearance-matched with the pin pipe, the pile head is provided with a second pin hole that is clearance-matched with the pin pipe, the pile cap is provided with a third pin hole that is clearance-matched with the pin pipe, and the pile cap is also provided with a high-pressure pipe joint connected to the third pin hole.

[0016] As a further solution of the present invention, the pipe ring is provided with a first gasket hole which is clearance-matched with the sealing gasket, and the pile cap is provided with a second gasket hole which is clearance-matched with the sealing gasket.

[0017] As a further solution of the present invention, a plurality of handles are fixedly mounted on the outside of the pile cap.

[0018] As a further solution of the present invention, the pile cap is further provided with a positioning hole matching the pin tube.

[0019] As a further solution of the present invention, the upper end of the pile head is provided with a boss matched with the inner ring of the pipe ring.

[0020] The prestressed concrete water jet special pipe pile grouting enlarged head pile forming process includes the following steps:

[0021] Step 1: Construction preparation

[0022] Level the site, lay out the lines for construction, and debug equipment;

[0023] Step 2: Install the pile body

[0024] First install the pile head and the first pipe section, then use a vibrating hammer to exert impact force on the pipe section to sink the pile;

[0025] Step 3: Connect the pile

[0026] When each pipe section sinks a certain distance, the next pipe section is installed until all pipe sections are installed, and then the pile cap is installed. All pipe sections, pile heads and pile caps form a pipe pile body;

[0027] Step 4: Pour the large concrete blocks

[0028] The pipe pile body is provided with a high-pressure water or cement slurry channel for passing high-pressure water or concrete, and the pile head is provided with a water hole connected to the high-pressure water or cement slurry channel;

[0029] The concrete passes through high-pressure water or cement slurry channels and water holes, and is finally poured near the pile head to form irregularly shaped large-head concrete blocks.

[0030] As a further scheme of the present invention, in step 3, during the sinking process of each pipe section, when the impact force exerted by the vibratory hammer on the pipe section reaches a preset value, the high-pressure water or cement slurry channel is connected to the high-pressure water, and the high-pressure water impacts the hard layer and rock and soil to assist the pipe section in sinking.

[0031] Compared with the prior art, the beneficial effects of the present invention are:

[0032] During construction, even when encountering special strata (such as medium-coarse sand strata, or sandy interlayers, riverbed pebbles, or backfill soil layers containing large stone blocks), the present invention uses a high-pressure water jet (with air) to impact the hard strata and cooperate with static pressure or hammering to play the role of other mechanical hole-guiding, solving the problem of the existing pipe piles being difficult to descend, and will not cause the pile body to break or bend during the construction process. When the designed elevation is reached, grouting is performed through the high-pressure water or cement slurry channel in the pipe pile body to form a spherical enlarged head (large-head concrete block) at the bottom of the pipe pile.

[0033] The enlarged head can increase the friction in the original soil and thus improve the bearing capacity of a single pile, and limit the settlement of the pile body. Especially when constructing a group of piles in a fixed site, it can eliminate the local displacement of the pile body, play a role in preventing the pile body from floating, and greatly alleviate the damage caused by the soil squeezing effect caused by the construction of pipe piles; it can effectively avoid causing the ground in the pile area to rise and bulge. The enlarged head formed by the pipe pile body can block the transfer of pollutants to groundwater in the local stratum. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic diagram of the enlarged head pile pipe for grouting prestressed concrete water jet special pipe pile;

[0035] Figure 2 is a schematic diagram of a pipe segment;

[0036] Figure 3 It is the internal schematic diagram of the pipe segment;

[0037] Figure 4 This is a schematic diagram of the pile head;

[0038] Figure 5 Schematic diagram of the pile cap. DETAILED DESCRIPTION

[0039] The present invention is described in detail below in conjunction with specific embodiments. The embodiments described below are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0040] Example 1

[0041] like Figures 1 to 5 As shown, the prestressed concrete water jet special pipe pile grouting enlarged head pile pipe includes a pipe pile body, a large-head concrete block 40 integrally connected to the lower end of the pipe pile body and having an irregular shape, the pipe pile body includes a pile cap 20, a multi-section pipe section 10, and an inverted cone-shaped pile head 30 from top to bottom, and the pile head 30 is located inside the large-head concrete block 40; the pipe pile body is provided with at least one high-pressure water or cement slurry channel along its axial direction, and the pile head 30 is provided with a water hole 33 connected to the high-pressure water or cement slurry channel.

[0042] The pipe segment 10 includes a reinforced concrete pipe body 11 and a pipe ring 15 integrally connected to the upper and lower ends of the reinforced concrete pipe body 11, a steel cage 13 is arranged inside the reinforced concrete pipe body 11, and the steel cage 13 is fixedly connected to the pipe ring 15; the high-pressure water or cement slurry channel includes a first channel 12 arranged along the axial direction of the pipe segment 10, and the upper and lower adjacent reinforced concrete pipe bodies 11, the lower end of the pipe segment 10 and the pile head 30, and the upper end of the pipe segment 10 and the pile cap 20 are all connected by setting a pin pipe 51.

[0043] In this embodiment, since a high-pressure water or cement slurry channel is provided, its inner diameter is greater than φ10 mm.

[0044] During the construction of the pipe pile, when the pressure applied to the pipe section 10 reaches a certain preset value, the high-pressure water or cement slurry channel is connected to the high-pressure water, and the high-pressure water is finally ejected from the material water hole 33 to impact the hard layer. The water and steam will flush part of the rock and soil, making it easier for the pipe pile body to reach the required depth position for construction. Among them, the inverted cone pile head 30 can effectively reduce the descending resistance.

[0045] After the pipe pile body reaches the required depth of construction, cement slurry can be injected into the ground through high-pressure water or cement slurry channels according to construction requirements. The cement slurry will mix with the original rock and soil profiles to form spherical irregular-shaped large-head concrete blocks 40 of φ600mm to φ1500mm, which can improve the bearing capacity and anti-floating performance of the pipe pile. After a large number of tests, it was found that the large-head concrete blocks 40 remain in a spherical shape, but the more irregular their appearance, the better their anti-floating performance.

[0046] When the prestressed pipe pile is under construction and encounters a special stratum (such as a medium-coarse sand stratum, or a sandy interlayer, a river pebble stratum, or a backfill soil layer containing large boulders), it is difficult for the pipe pile body to move downward. If static pressure or hammering is performed forcibly, it is easy to cause the pile body to break or bend and deform. At this time, a high-pressure water jet (with air) ejected through a high-pressure water or cement slurry channel impacts the hard stratum and cooperates with static pressure or hammering to play the role of drilling brought by other machines. At the same time, when the designed elevation is reached, the water vapor valve is closed and the shotcrete valve is opened; grouting is performed through the high-pressure water or cement slurry channel in the pipe pile body, and the grouting amount reaches twice the outer diameter of the pipe pile body (or larger, and the grouting amount can be determined according to geological conditions), forming a spherical enlarged head (i.e., a large-head concrete block 40) at the bottom of the pipe pile body.

[0047] The enlarged head can increase the friction in the original soil and thus improve the bearing capacity of a single pile, and limit the settlement of the pile body. Especially when constructing a group of piles in a fixed site, it can eliminate the local displacement of the pile body, play a role in preventing the pile body from floating, and greatly alleviate the damage caused by the soil squeezing effect caused by the pipe pile construction. Avoid causing the ground in the pile area to rise or bulge.

[0048] The pile body forms an enlarged head which can block the local strata and prevent the transfer of pollutants to groundwater.

[0049] Example 2

[0050] The prestressed concrete water jet special pipe pile grouting enlarged head pile forming process includes the following steps:

[0051] Step 1: Construction preparation

[0052] Level the site, lay out the lines for construction, and debug equipment;

[0053] Step 2: Install the pile body

[0054] First install the pile head and the first pipe section, then use a vibrating hammer to exert impact force on the pipe section to sink the pile;

[0055] Step 3: Connect the pile

[0056] When each pipe section sinks a certain distance, the next pipe section is installed until all pipe sections are installed, and then the pile cap is installed. All pipe sections, pile heads and pile caps form a pipe pile body;

[0057] Step 4: Pour the large concrete blocks

[0058] The pipe pile body is provided with a high-pressure water or cement slurry channel for passing high-pressure water or concrete, and the pile head is provided with a water hole connected to the high-pressure water or cement slurry channel;

[0059] The concrete passes through high-pressure water or cement slurry channels and water holes, and is finally poured near the pile head to form irregularly shaped large-head concrete blocks.

[0060] In step 3, during the sinking process of each pipe section, when the impact force exerted by the vibratory hammer on the pipe section reaches a preset value, the high-pressure water or cement slurry channel is connected to the high-pressure water, and the high-pressure water impacts the hard layer and rock and soil to assist the pipe section in sinking.

[0061] In this embodiment, high-pressure water generally refers to water flow with a water pressure greater than 20 MPa.

[0062] Example 3

[0063] To ensure sealing, a sealing gasket 52 is sleeved on the outside of the pin tube 51 .

[0064] Among them, for the convenience of installation; the pipe ring 15 is provided with a first pin hole 151 which is a clearance fit with the pin tube 51, the pile head 30 is provided with a second pin hole 32 which is a clearance fit with the pin tube 51, the pile cap 20 is provided with a third pin hole which is a clearance fit with the pin tube 51, and the pile cap 20 is also provided with a high-pressure pipe joint 21 connected to the third pin hole.

[0065] The pipe ring 15 is provided with a first gasket hole 152 which is clearance-matched with the sealing gasket 52 , and the pile cap 20 is provided with a second gasket hole which is clearance-matched with the sealing gasket 52 .

[0066] The high-pressure pipe connector 21 can be used to connect high-pressure water externally.

[0067] Example 4

[0068] To facilitate hoisting and installation, a plurality of handles 22 are fixedly mounted on the outside of the pile cap 20 .

[0069] Example 5

[0070] To ensure accurate installation and docking: the pile cap 20 is also provided with a positioning hole 23 matching the pin tube 51 .

[0071] Example 6

[0072] To ensure the installation effect, a boss 31 matching the inner ring of the pipe ring 15 is provided at the upper end of the pile head 30 .

[0073] Example 7

[0074] When a grouting pump is used to inject cement slurry into the ground through high-pressure water or cement slurry channels, the output grouting pressure of the grouting pump changes in a pulsed manner, and the pulse change waveform presents a bell-shaped wave structure. According to the test, the pulse change waveform is a rectangular pulse, a square wave pulse, a trapezoidal wave structure, and a triangular wave structure. The surface of the final large-head concrete block presents a relatively regular uneven structure; while the sharp pulse and sawtooth wave structure are not much different from the rectangular pulse, and are relatively regular concave-convex structures; if it is a step wave, several thorns will be formed on the surface of the large-head concrete block, similar to the head of a meteor hammer. Only when the pulse change waveform presents a bell-shaped wave structure, it will form a relatively irregular spherical shape, and it is more random. The shapes of two adjacent large-head concrete blocks are quite different, which is very suitable for construction in complex terrain.

[0075] In addition, it should be understood that those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. Prestressed concrete water jet special pipe pile grouting enlarged head pile pipe, characterized by: The invention comprises a pipe pile body and a large-head concrete block (40) integrally connected to the lower end of the pipe pile body and having an irregular shape. The pipe pile body comprises a pile cap (20), a plurality of pipe sections (10), and an inverted cone-shaped pile head (30) from top to bottom. The pile head (30) is located inside the large-head concrete block (40). The pipe pile body is provided with at least one high-pressure water or cement slurry channel along its axial direction, and the pile head (30) is provided with a water hole (33) connected to the high-pressure water or cement slurry channel.

2. The prestressed concrete water jet special pipe pile grouting enlarged head pile pipe according to claim 1, characterized in that: The pipe segment (10) comprises a reinforced concrete pipe body (11), and a pipe ring (15) integrally connected to the upper and lower ends of the reinforced concrete pipe body (11), wherein a steel cage (13) is arranged inside the reinforced concrete pipe body (11), and the steel cage (13) is fixedly connected to the pipe ring (15); the high-pressure water or cement slurry channel comprises a first channel (12) arranged along the axial direction of the pipe segment (10), and the upper and lower adjacent reinforced concrete pipe bodies (11), the lower end of the pipe segment (10) and the pile head (30), and the upper end of the pipe segment (10) and the pile cap (20) are all connected by means of a pin pipe (51).

3. The prestressed concrete water jet special pipe pile grouting enlarged head pile pipe according to claim 2, characterized in that: The pin tube (51) is sleeved with a sealing gasket (52) on its exterior.

4. The prestressed concrete water jet special pipe pile grouting enlarged head pile pipe according to claim 3, characterized in that: The pipe ring (15) is provided with a first pin hole (151) which is clearance-matched with the pin pipe (51), the pile head (30) is provided with a second pin hole (32) which is clearance-matched with the pin pipe (51), the pile cap (20) is provided with a third pin hole which is clearance-matched with the pin pipe (51), and the pile cap (20) is further provided with a high-pressure pipe joint (21) which is connected with the third pin hole.

5. The prestressed concrete water jet special pipe pile grouting enlarged head pile pipe according to claim 3, characterized in that: The pipe ring (15) is provided with a first gasket hole (152) which is clearance-matched with the sealing gasket (52), and the pile cap (20) is provided with a second gasket hole which is clearance-matched with the sealing gasket (52).

6. The prestressed concrete water jet special pipe pile grouting enlarged head pile pipe according to claim 1, characterized in that: A plurality of handles (22) are fixedly mounted on the outside of the pile cap (20).

7. The prestressed concrete water jet special pipe pile grouting enlarged head pile pipe according to claim 2, characterized in that: The pile cap (20) is also provided with a positioning hole (23) matching the pin tube (51).

8. The prestressed concrete water jet special pipe pile grouting enlarged head pile pipe according to claim 2, characterized in that: The upper end of the pile head (30) is provided with a boss (31) adapted to the inner ring of the pipe ring (15).

9. Prestressed concrete water jet special pipe pile grouting enlarged head pile forming process, characterized in that: The following steps are involved: Step 1: Construction preparation Level the site, lay out the lines for construction, and debug equipment; Step 2: Install the pile body Firstly, the pile head (30) and the first pipe section (10) are installed, and then a vibrating hammer is used to exert an impact force on the pipe section (10) to sink the pile; Step 3: Connect the pile After each pipe section (10) sinks a certain distance, the next pipe section (10) is installed until all the pipe sections (10) are installed, and then the pile cap (20) is installed, and all the pipe sections (10), the pile head (30) and the pile cap (20) form a pipe pile body; Step 4: Pour the large concrete blocks The pipe pile body is provided with a high-pressure water or cement slurry channel for passing high-pressure water or concrete, and the pile head (30) is provided with a water hole (33) connected to the high-pressure water or cement slurry channel; Concrete passes through high-pressure water or cement slurry channels and water holes (33), and is finally poured near the pile head (30) to form irregularly shaped large-head concrete blocks.

10. The prestressed concrete water jet special pipe pile grouting enlarged head pile forming process according to claim 9, characterized in that: In step 3, during the sinking process of each pipe segment (10), when the impact force exerted by the vibrating hammer on the pipe segment (10) reaches a preset value, the high-pressure water or cement slurry channel is connected to the high-pressure water, and the high-pressure water impacts the hard layer and rock and soil to assist the pipe segment (10) to sink.

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