Combined type post-grouting device for cast-in-place pile

Abstract

The utility model relates to the technical field of cast-in-place pile construction, and discloses a composite post-grouting device for a cast-in-place pile. The combined type post-grouting device for the cast-in-place pile comprises a top plate, a bottom plate, a connecting cylinder, a slurry storage bag and a grouting assembly. The top plate and the bottom plate are respectively provided with a first through hole and a second through hole; the connecting cylinder is provided with a hollow cavity, the top plate and the bottom plate are arranged at the two ends of the connecting cylinder, and the two through holes and the hollow cavity are connected to form a channel. A slurry storage cavity is defined by the slurry storage bag, the top plate, the outer wall of the connecting cylinder and the bottom plate; an open grouting pipe in the grouting assembly is arranged in the channel, and one end of a closed grouting pipe extends into the grout storage cavity. The post-grouting device is arranged at the bottom of a drilled hole, after concrete is poured into the drilled hole to form a cast-in-place pile, grouting is conducted on the pile bottom stratum through the open type grouting pipe, then grouting is conducted on the grout storage bag through the closed type grouting pipe, and finally expansion can be conducted at the pile bottom to form an expanded head. After the concrete in the drilled hole is solidified to form the cast-in-place pile, the friction resistance and the pulling resistance of the pile body can be improved due to the expansion head, and the bearing capacity of the cast-in-place pile is higher.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of cast-in-place pile construction technology, and particularly relates to a composite post-grouting device for cast-in-place pile. BACKGROUND

[0002] The cast-in-place pile can be applied to various construction projects such as high-rise buildings, bridges and tunnels, and can provide a solid foundation for the safety and stability of buildings. The cast-in-place pile is a pile formed by directly drilling a hole at a pile site and then pouring concrete or reinforced concrete. The specific construction process is as follows: first, a hole is formed at a pile site with suitable geological conditions by using a rotary drilling machine or other drilling equipment, and after the hole is formed, the hole bottom sediment is removed by using a vacuum suction sediment method, a water jet sediment extraction method, a slurry replacement method and a sediment extraction method. Then, the pre-prepared reinforcement cage is placed in the hole, and then the concrete is poured or directly poured, and finally the pile body is formed.

[0003] However, after the current cast-in-place pile construction is completed, the contact area of the pile body is fixed, which limits the friction resistance and uplift resistance of the cast-in-place pile, the overall bearing capacity is small, and the stability of the building arranged on the cast-in-place pile is poor. CONTENT OF THE UTILITY MODEL

[0004] Therefore, the utility model provides a composite post-grouting device for cast-in-place pile to solve the problems of limited friction resistance and uplift resistance of the cast-in-place pile, small overall bearing capacity and poor stability of the building arranged on the cast-in-place pile.

[0005] In a first aspect, the utility model provides a composite post-grouting device for cast-in-place pile arranged at the bottom of a hole, which comprises:

[0006] A top plate having a first through hole;

[0007] A bottom plate having a second through hole;

[0008] A connecting cylinder having a hollow cavity with two open ends, the top plate and the bottom plate are arranged at the two ends of the connecting cylinder respectively, and the first through hole, the hollow cavity and the second through hole are connected to form a channel;

[0009] A slurry storage bag arranged around the connecting cylinder, the two ends of the slurry storage bag are connected with the top plate and the bottom plate respectively, and the slurry storage bag, the top plate, the outer wall of the connecting cylinder and the bottom plate form a slurry storage cavity;

[0010] A grouting assembly comprising an open grouting pipe and a closed grouting pipe, the open grouting pipe is arranged in the channel, and one end of the closed grouting pipe extends into the slurry storage cavity.

[0011] ADVANTAGEOUS EFFECTS

[0012] When the borehole is drilled, the post-grouting device is placed at the bottom of the borehole, and then concrete is poured into the borehole. After the concrete is poured, grout is injected into the bottom of the pile through the open grouting pipe, so that the grout seeps into the surrounding stratum, and then grout is injected into the grout storage cavity through the closed grouting pipe, so that the grout storage bag expands and expands, compacts and consolidates the surrounding stratum and the grout, and finally forms an enlarged head at the bottom of the pile. When the concrete in the borehole solidifies to form a cast-in-place pile, the enlarged head at the bottom of the pile can increase the contact area with the stratum, improve the friction resistance and uplift resistance of the pile body, and thus improve the bearing capacity of the cast-in-place pile. The building provided with the cast-in-place pile is more stable and safer.

[0013] In an alternative embodiment, the cross-section of the channel perpendicular to its axis is circular or elliptical.

[0014] In an alternative embodiment, the size of the first through-hole is smaller than the size of the second through-hole.

[0015] In an alternative embodiment, a reinforcing assembly is arranged in the channel.

[0016] In an alternative embodiment, the reinforcing assembly comprises a plurality of transverse reinforcing members arranged in the second through-hole.

[0017] In an alternative embodiment, the reinforcing assembly further comprises a plurality of vertical reinforcing members arranged on the inner wall of the channel in a circumferential direction.

[0018] In an alternative embodiment, one end of the vertical reinforcing member is connected to one end of the transverse reinforcing member.

[0019] Advantages

[0020] The arrangement of the reinforcing assembly can improve the structural strength of the post-grouting device and make it more durable.

[0021] In an alternative embodiment, one end of the closed grouting pipe penetrates the top plate and extends into the grout storage cavity.

[0022] In an alternative embodiment, one end of the open grouting pipe and the closed grouting pipe is provided with a one-way valve.

[0023] Advantages

[0024] The arrangement of the one-way valve can prevent the backflow of grout.

[0025] In an alternative embodiment, the grout storage bag is made of chemical fiber fabric material.

[0026] Advantages

[0027] The grout storage bag made of chemical fiber fabric material can expand and expand, thereby forming an enlarged head at the bottom of the pile. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the specific embodiment of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiment or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0029] Figure 1 It is a front view of the composite post-grouting device for cast-in-place pile in the embodiment 1 of the present application.

[0030] Figure 2 It is a top view of the composite post-grouting device for cast-in-place pile in the embodiment 1 of the present application.

[0031] Figure 3 It is a schematic view of the formed drilling in the cast-in-place pile construction process in the embodiment 1 of the present application.

[0032] Figure 4 It is a schematic view of setting the post-grouting device in the cast-in-place pile construction process in the embodiment 1 of the present application.

[0033] Figure 5 It is a schematic view of forming the enlarged head by post-grouting in the cast-in-place pile construction process in the embodiment 1 of the present application.

[0034] Figure 6 It is a top view of the composite post-grouting device for cast-in-place pile in the embodiment 2 of the present application.

[0035] Figure 7 It is a bottom view of the composite post-grouting device for cast-in-place pile in the embodiment 3 of the present application.

[0036] Figure 8 It is a bottom view of the composite post-grouting device for cast-in-place pile in the embodiment 4 of the present application.

[0037] Figure 9 It is a schematic view of the connection between the composite post-grouting device for cast-in-place pile and the pile bottom grouting device in the embodiment 5 of the present application.

[0038] Figure 10 It is a schematic view of the composite post-grouting device for cast-in-place pile and the pile bottom grouting device being placed at the bottom of the drilling in the embodiment 5 of the present application.

[0039] Figure 11 It is a schematic view of the composite post-grouting device for cast-in-place pile and the pile bottom grouting device forming the enlarged head at the pile bottom in the embodiment 5 of the present application.

[0040] Explanation of reference signs:

[0041] 1, drilling;

[0042] 2. The composite post-pouring grouting device for cast-in-place pile;

[0043] 21. The top plate;

[0044] 22. The bottom plate;

[0045] 23. The connecting cylinder;

[0046] 24. The grout storage bag;

[0047] 251. The open grouting pipe, 252. The closed grouting pipe, 253. The one-way valve;

[0048] 261. The horizontal reinforcing member, 262. The vertical reinforcing member;

[0049] 3. The pile bottom grouting device, 31. The fixed plate, 32. The grouting pipe, 33. The grouting capsule. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by the person skilled in the art without making creative efforts are within the protection scope of the present application.

[0051] Embodiment 1

[0052] The embodiments of the present application will be described below in combination with Figures 1 to 5

[0053] According to the embodiments of the present application, on the one hand, a composite post-pouring grouting device 2 for cast-in-place pile is provided, which comprises a top plate 21, a bottom plate 22, a connecting cylinder 23, a grout storage bag 24 and a grouting assembly. The top plate 21 has a first through hole, and the bottom plate 22 has a second through hole; the connecting cylinder 23 has a hollow cavity with two open ends, and the top plate 21 and the bottom plate 22 are respectively arranged at the two ends of the connecting cylinder 23, and the first through hole, the hollow cavity and the second through hole are communicated to form a channel; the grout storage bag 24 is arranged at the periphery of the connecting cylinder 23, and the two ends thereof are respectively connected with the top plate 21 and the bottom plate 22, and the grout storage bag 24, the top plate 21, the outer wall of the connecting cylinder 23 and the bottom plate 22 enclose a grout storage cavity; the grouting assembly comprises an open grouting pipe 251 and a closed grouting pipe 252, the open grouting pipe 251 is arranged in the channel, and one end of the closed grouting pipe 252 extends into the grout storage cavity.

[0054] ​The back grouting device 2 of the composite bored pile is arranged at the bottom of the drill hole 1, and a top plate 21, a bottom plate 22 and a connecting cylinder 23 form a main body structure of the back grouting device and are main load-bearing components. A slurry storage bag 24 and a grouting assembly are mainly used for subsequent grouting. Specifically, the top plate 21, the bottom plate 22 and the connecting cylinder 23 are generally made of metal and have sufficient hardness and support strength. For example, the top plate 21 and the bottom plate 22 can be steel plates, and the connecting cylinder 23 is a steel cylinder. The top plate 21, the connecting cylinder 23 and the bottom plate 22 can be connected by welding. The top plate 21 and the bottom plate 22 need to be provided with holes, i.e., a first through hole on the top plate 21 and a second through hole on the bottom plate 22, and the middle part of the connecting cylinder 23 has a hollow cavity. In this way, after the top plate 21 and the bottom plate 22 are arranged at the two ends of the connecting cylinder 23, the first through hole, the hollow cavity and the second through hole can be connected to form a channel. The channel is provided for two purposes: one is to facilitate the subsequent arrangement of an open grouting pipe 251, and the other is to enable the back grouting device to be integrated with the pile body of the bored pile. The bag body of the slurry storage bag 24 is flexible and expandable or inflatable. The slurry storage bag 24 is arranged outside the connecting cylinder 23 and is connected and sealed at both ends with the top plate 21 and the bottom plate 22, so as to form a closed slurry storage cavity together with the top plate 21, the outer wall of the connecting cylinder 23 and the bottom plate 22. The open grouting pipe 251 is used for open grouting, i.e., grouting into the open space at the bottom of the pile, so the open grouting pipe 251 is arranged in the channel and can be welded to the inner wall of the connecting cylinder 23. The closed grouting pipe 252 is used for closed grouting, i.e., grouting into the closed space in the slurry storage cavity, so one end of the closed grouting pipe 252 needs to extend into the slurry storage cavity. The open grouting pipe 251 and the closed grouting pipe 252 can be one or more. The injected slurry can be cement slurry or cement mortar.

[0055] After the drill hole 1 is drilled, the back grouting device is placed at the bottom of the drill hole 1, and then concrete is poured into the drill hole 1. The poured concrete is shaped into the pile body of the bored pile. After the concrete is poured, the back grouting device is used for grouting. The grouting process includes open grouting and closed grouting. After grouting is performed at the bottom of the pile through the open grouting pipe 251, the slurry seeps into the surrounding soil, so that the slurry is integrated with the surrounding soil after the slurry is solidified. The closed grouting pipe 252 is used for grouting into the slurry storage cavity. As the amount of grouting increases, the slurry storage bag 24 gradually expands, which presses the surrounding soil, so that the soil is solidified with the slurry by pressure, and finally expands and solidifies into an enlarged head at the bottom of the pile. When the concrete in the drill hole 1 is solidified, the back grouting device is integrated with the bored pile.

[0056] Because the volume of the enlarged head at the bottom of the pile is larger than the space at the bottom of the original drill hole 1, the contact area between the cast-in-place pile and the soil is increased, and the soil around the enlarged head is consolidated by the slurry during the forming of the enlarged head, so the frictional resistance between the cast-in-place pile and the soil and the uplift resistance of the cast-in-place pile are increased, the bearing capacity of the cast-in-place pile is improved, and the building arranged on the cast-in-place pile is more stable and safe.

[0057] In one embodiment, the slurry storage bag 24 is made of a chemical fiber adhesive tape material.

[0058] The chemical fiber adhesive tape material is a kind of adhesive tape material made of artificial chemical fibers as a base material, which has strong wear resistance and good elasticity. The slurry storage bag 24 made of this material is not easy to break during grouting, and can expand elastically with the increase of the grouting amount, which is beneficial to the formation of the enlarged head structure.

[0059] In some embodiments, the cross section of the channel perpendicular to its axis is circular or elliptical.

[0060] Because the drill hole 1 is generally a circular hole, that is, the cross section of the drill hole 1 perpendicular to its axis is circular, the shapes of the top plate 21, the bottom plate 22 and the connecting cylinder 23 in the corresponding post-grouting device are matched with it, that is, the top plate 21 and the bottom plate 22 are circular plates, and the connecting cylinder 23 is a cylindrical cylinder. The first through hole on the top plate 21 and the second through hole on the bottom plate 22 are circular or elliptical holes, and correspondingly, the hollow cavity of the connecting cylinder 23 is a cylindrical cavity or an elliptical cylindrical cavity. Of course, in other embodiments, the cross section of the channel perpendicular to its axis can be other shapes, such as triangular, rectangular, etc., but the processing difficulty is slightly higher than that of circular or elliptical.

[0061] Specifically, as shown in Figure 1 , Figure 2 In this embodiment, the cross section of the channel perpendicular to its axis is circular, and the diameter of the first through hole, the diameter of the second through hole and the diameter of the circular cross section of the hollow cavity are equal.

[0062] In one embodiment, one end of the closed grouting pipe 252 penetrates the top plate 21 and extends into the slurry storage cavity.

[0063] Small holes can be provided on the plate body of the top plate 21 for the closed grouting pipe 252 to pass through, and one end of the closed grouting pipe 252 extends into the slurry storage cavity to inject slurry into the slurry storage cavity.

[0064] In another embodiment, the closed grouting pipe 252 can also penetrate the slurry storage bag 24 and extend into the slurry storage cavity, but this way is not easy to seal at the pipe passage compared to the way of penetrating from the top plate 21, so generally the closed grouting pipe 252 is still selected to penetrate from the top plate 21 and extend into the slurry storage cavity.

[0065] In one embodiment, a one-way valve 253 is provided at one end of the open grouting pipe 251 and the closed grouting pipe 252.

[0066] Setting a one-way valve 253 can prevent slurry backflow and ensure that the slurry can be injected smoothly.

[0067] The construction process of post-grouting piles using the composite post-grouting device 2 provided in this embodiment is described below:

[0068] Firstly, as Figure 3 As shown, borehole 1 is drilled according to design requirements using drilling rigs and other equipment.

[0069] Then as Figure 4 As shown, the post-grouting device is placed at the bottom of borehole 1, and concrete is poured into borehole 1.

[0070] For example Figure 5 As shown, grout is first injected into the soil at the bottom of the pile through the open grouting pipe 251, allowing the grout to seep into the surrounding soil. Next, grout is injected into the storage space through the closed grouting pipe 252. As the closed grouting proceeds, the storage bag 24 expands, compressing the surrounding soil. This compacts and solidifies the soil with the grout. Finally, after the grout and concrete have set, an enlarged head structure is formed at the bottom of the pile.

[0071] Example 2

[0072] The difference between this embodiment and embodiment 1 is that the cross-section of the channel perpendicular to its axis is elliptical. The rest of the structure is the same as that of embodiment 1 and will not be described again.

[0073] like Figure 6 As shown, the cross-section of the channel perpendicular to its axis is elliptical, that is, the cross-sections of the first through hole, the second through hole, and the hollow cavity are all elliptical and of equal size.

[0074] Example 3

[0075] The difference between this embodiment and embodiment 1 is that the size of the first through hole is smaller than the size of the second through hole. The rest of the structure is the same as that of embodiment 1 and will not be described again.

[0076] Specifically, such as Figure 7 As shown, although both the first and second through holes are circular, the first through hole has a smaller diameter and the second through hole has a larger diameter. The open grouting pipe 251 can pass directly through the base plate 22 during installation. In other embodiments, the open grouting pipe 251 can also be made bent to pass through the second through hole.

[0077] In another embodiment, both the first through hole and the second through hole can be elliptical holes, and the size of the first through hole is still smaller than the size of the second through hole.

[0078] Example 4

[0079] The difference between this embodiment and embodiment 1 is that a reinforcing component is provided in the channel; the rest of the structure is the same as that of embodiment 1 and will not be described again.

[0080] Furthermore, in some embodiments, the reinforcement component includes a plurality of transverse reinforcement members 261 disposed crosswise in the second through hole.

[0081] The transverse reinforcement 261 is arranged radially along the second through hole, and multiple transverse reinforcements 261 can be arranged at an angle to each other at the center of the second through hole.

[0082] In some embodiments, the reinforcement component further includes a plurality of vertical reinforcement members 262 disposed at intervals along the circumferential direction of the channel on its inner wall.

[0083] The vertical reinforcement 262 is arranged parallel to the axial direction of the hollow cavity, that is, the vertical reinforcement 262 is parallel to the open grouting pipe 251 and perpendicular to the horizontal reinforcement 261. Multiple vertical reinforcements 262 can be fixed at intervals on the wall surface of the hollow cavity.

[0084] In some embodiments, one end of the vertical reinforcement 262 is connected to one end of the horizontal reinforcement 261.

[0085] Specifically, such as Figure 8 As shown, in this embodiment, both the horizontal reinforcement 261 and the vertical reinforcement 262 are steel bars, with a total of two horizontal reinforcements 261 and four vertical reinforcements 262. The two horizontal reinforcements 261 are arranged in a cross shape, and the bottom end of each vertical reinforcement 262 is connected to the end of one horizontal reinforcement 261 by welding.

[0086] In other embodiments, the horizontal reinforcement 261 and the vertical reinforcement 262 may not be connected. That is, the end of the horizontal reinforcement 261 is directly connected to the base plate 22, and the vertical reinforcement 262 is connected to the inner wall of the connecting cylinder 23. The ends of the horizontal reinforcement 261 and the vertical reinforcement 262 are staggered and not connected.

[0087] In other embodiments, the number of horizontal reinforcement members 261 and vertical reinforcement members 262 can also be adjusted, and this embodiment does not impose specific limitations.

[0088] Example 5

[0089] In this embodiment, as Figures 9 to 11 As shown, the composite post-grouting device 2 for cast-in-place piles can be used in combination with the pile bottom grouting device 3 with patent number ZL201980000970.2.

[0090] The post-grouting device 2 and the pile bottom grouting device 3 of the cast-in-place pile composite post-grouting device of the embodiment are connected, with the post-grouting device on top and the pile bottom grouting device 3 on bottom. The specific connection mode can be to weld the bottom plate 22 of the post-grouting device with the fixed plate 31 of the pile bottom grouting device 3, but the open grouting pipe 251 in the post-grouting device needs to pass through the through hole of the pile bottom grouting device 3 so as to smoothly perform open grouting.

[0091] After connection, the whole device is placed at the bottom of the drill hole 1. In addition to open grouting through the open grouting pipe 251 to the pile bottom stratum and closed grouting through the closed grouting pipe 252 to the grout storage cavity, grouting to the grouting capsule 33 of the pile bottom grouting device 3 through the grouting pipe 32 is also needed. Both the post-grouting device and the pile bottom grouting device 3 can form an enlarged head, and finally form an enlarged head structure as shown in Figure 11 The combination of the two devices can further enhance the frictional resistance and the uplift resistance of the cast-in-place pile.

[0092] Although the embodiments of the present application are described in conjunction with the drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.

Claims

1. A composite post-grouting device for cast-in-place piles, installed at the bottom of the borehole (1), characterized in that, include: Top plate (21), the top plate (21) having a first through hole; A base plate (22) having a second through hole; The connecting cylinder (23) has a hollow cavity with openings at both ends. The top plate (21) and the bottom plate (22) are respectively disposed at both ends of the connecting cylinder (23), and the first through hole, the hollow cavity and the second through hole are connected to form a channel. The slurry storage bag (24) is located on the periphery of the connecting cylinder (23), and its two ends are connected to the top plate (21) and the bottom plate (22) respectively. The slurry storage bag (24), the top plate (21), the outer wall of the connecting cylinder (23) and the bottom plate (22) form a slurry storage cavity. The grouting assembly includes an open grouting pipe (251) and a closed grouting pipe (252), wherein the open grouting pipe (251) is disposed in the channel and one end of the closed grouting pipe (252) extends into the grout storage cavity.

2. The composite post-grouting device for cast-in-place piles according to claim 1, characterized in that, The cross-section of the channel perpendicular to its axis is circular or elliptical.

3. The composite post-grouting device for cast-in-place piles according to claim 2, characterized in that, The size of the first through hole is smaller than the size of the second through hole.

4. The composite post-grouting device for cast-in-place piles according to any one of claims 1-3, characterized in that, The channel is equipped with reinforcement components.

5. The composite post-grouting device for cast-in-place piles according to claim 4, characterized in that, The reinforcement assembly includes a plurality of transverse reinforcement members (261) arranged crosswise in the second through hole.

6. The composite post-grouting device for cast-in-place piles according to claim 5, characterized in that, The reinforcement assembly also includes a plurality of vertical reinforcement members (262) spaced circumferentially along the inner wall of the channel.

7. The composite post-grouting device for cast-in-place piles according to claim 6, characterized in that, One end of the vertical reinforcement (262) is connected to one end of the horizontal reinforcement (261).

8. The composite post-grouting device for cast-in-place piles according to claim 1, characterized in that, One end of the closed grouting pipe (252) passes through the top plate (21) and extends into the grout storage cavity.

9. The composite post-grouting device for cast-in-place piles according to claim 1, characterized in that, One end of the open grouting pipe (251) and the closed grouting pipe (252) is provided with a one-way valve (253).

10. The composite post-grouting device for cast-in-place piles according to claim 1, characterized in that, The slurry storage bag (24) is made of chemical fiber rubber sheet material.

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