Telescopic reaction frame, negative pressure vacuum loading device and pile foundation bearing capacity testing equipment

Abstract

The invention discloses a telescopic reaction frame, a negative pressure vacuum loading device and pile foundation bearing capacity testing equipment, the telescopic reaction frame comprises a central supporting unit and umbrella leaves, the central supporting unit is pressed on the top of a jack and comprises a center shaft and a plurality of telescopic rods, the telescopic rods are distributed on the periphery of the center shaft at intervals in the circumferential direction of the center shaft, and the umbrella leaves are arranged on the center shaft; each telescopic rod forms an included angle with the middle shaft, and one end is connected with the middle shaft; the umbrella leaf covers the center shaft, the middle of the umbrella leaf is hinged to the top end of the center shaft, and the umbrella leaf is connected with the ends, away from the center shaft, of the telescopic rods; when the telescopic rod extends, the umbrella leaves are stressed to expand outwards, and the telescopic counter-force frame is in an expanded state, and when the telescopic rod retracts, the umbrella leaves are stressed to contract inwards, and the telescopic counter-force frame is in a contracted state. Thus, during testing, the telescopic counter-force frame can be unfolded only through extension of the telescopic rod, assembly is not needed, the installation time is greatly shortened, during storage and carrying, the telescopic counter-force frame can be contracted only through contraction of the telescopic rod, disassembly is not needed, and efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of pile foundation engineering testing technology, specifically to a retractable reaction frame, a negative pressure vacuum loading device, and a pile foundation bearing capacity testing equipment. Background Technology

[0002] Pile foundations are widely used in building, transportation, municipal, water conservancy, and marine engineering. Meeting design requirements for pile bearing capacity is one of the fundamental conditions for ensuring building safety. However, during the construction of various pile types, the bearing capacity of the piles often fails to meet design requirements due to various reasons, affecting the normal working characteristics of the pile foundation and posing unpredictable potential dangers to the entire building. Therefore, conducting pile bearing capacity assessments and promptly identifying and eliminating problems becomes a crucial step in ensuring the quality of engineering construction.

[0003] Vacuum negative pressure static pile testing is a novel pile testing method. This method involves creating a vacuum within a negative pressure space between the reaction frame and the test pile site, and then using atmospheric pressure to provide the jack loading reaction force. This method offers a straightforward and reliable testing mechanism with minimal safety risks. It eliminates the need for anchor piles, reducing construction time, and facilitates large-scale sampling inspections. However, existing vacuum negative pressure loading devices use reaction frames assembled from multiple trusses, requiring disassembly for transport and reassembly for testing. This assembly process is cumbersome and time-consuming. Summary of the Invention

[0004] The main objective of this invention is to provide a retractable reaction frame, a negative pressure vacuum loading device, and a pile foundation bearing capacity testing device to solve the aforementioned problems.

[0005] To achieve the above objectives, the present invention proposes a retractable reaction frame for use in a vacuum negative pressure loading device, the retractable reaction frame comprising: A central support unit, used to press against the top of the jack in the vacuum negative pressure loading device, includes a central shaft and multiple telescopic rods. The central shaft extends vertically, and the multiple telescopic rods are spaced circumferentially around the central shaft. Each telescopic rod is angled to the central shaft, and one end is connected to the central shaft; and... The umbrella leaf is mounted on the central axis, and its middle part is hinged to the top of the central axis. The umbrella leaf is connected to the end of the plurality of telescopic rods away from the central axis. When the telescopic rod extends, the umbrella leaf is forced to unfold outward, and the telescopic reaction frame is in the unfolded state. When the telescopic rod retracts, the umbrella leaf is forced to retract inward, and the telescopic reaction frame is in the retracted state.

[0006] Optionally, the umbrella leaf includes: Multiple umbrella blades are spaced apart circumferentially along the umbrella leaf, and the top end of each umbrella blade is hinged to the top end of the central axis; and, Multiple connecting pieces, with two connecting pieces connecting any two adjacent umbrella pieces, and one connecting piece rotatably connected to one side of each connecting piece, and one umbrella piece rotatably connected to the other side of each connecting piece; The end of each telescopic rod away from the central axis is connected to the umbrella flap or the connecting piece.

[0007] Optionally, one side of each connecting piece is connected to a connecting piece via a first rotating shaft, and the other side of each connecting piece is connected to a slat via a second rotating shaft.

[0008] Optionally, the umbrella slats and the connecting piece are both made of steel. The width of the umbrella leaf and the width of the connecting piece are gradually increased from the end closest to the center of the umbrella leaf to the end furthest from the center of the umbrella leaf.

[0009] Optionally, the gap between each connecting piece and its adjacent connecting piece is filled with a first seal. The gap between each connecting piece and its adjacent umbrella piece is filled with a second seal.

[0010] Optionally, the first sealing element is a sealing strip, and is connected to the connecting piece by structural adhesive; The second sealing element is a sealing strip, and it is connected to the connecting piece and the umbrella piece by structural adhesive.

[0011] Optionally, the central support unit further includes a lifting rod, which is located at the bottom end of the central shaft and is used to abut against the top of the jack.

[0012] The present invention also provides a vacuum negative pressure loading device for pile foundation bearing capacity testing, comprising: A retractable reaction frame, when in the deployed state, has its umbrella-shaped blades inserted into the surface of the test pile site to form a negative pressure space with the test pile site. A jack is used to press down on the top of the test pile, and the retractable reaction frame is pressed down on the top of the jack. At least one sealing membrane is provided, covering the retractable reaction frame, and the periphery of the sealing membrane is used for insertion into the surface of the test pile site; and, A vacuum pumping assembly, connected to the negative pressure space, is used to extract air from the negative pressure space; The retractable reaction frame includes: A central support unit, used to press against the top of the jack in the vacuum negative pressure loading device, includes a central shaft and multiple telescopic rods. The central shaft extends vertically, and the multiple telescopic rods are spaced circumferentially around the central shaft. Each telescopic rod is angled to the central shaft, and one end is connected to the central shaft; and... The umbrella leaf is mounted on the central axis, and its middle part is hinged to the top of the central axis. The umbrella leaf is connected to the end of the plurality of telescopic rods away from the central axis. When the telescopic rod extends, the umbrella leaf is forced to unfold outward, and the telescopic reaction frame is in the unfolded state. When the telescopic rod retracts, the umbrella leaf is forced to retract inward, and the telescopic reaction frame is in the retracted state.

[0013] Optionally, it also includes an alignment component, the alignment component further comprising: A laser emitter, detachably mounted on the jack or the test pile and located on the centerline of the jack or the test pile, the laser emitter being used to emit a laser; and, A laser receiver is disposed within the central axis of the retractable reaction frame and located on the center line of the central axis, for receiving laser light from the laser emitter.

[0014] The present invention also provides a pile foundation bearing capacity testing device, including a vacuum negative pressure loading device; The vacuum negative pressure loading device includes: A retractable reaction frame, when in the deployed state, has its umbrella-shaped blades inserted into the surface of the test pile site to form a negative pressure space with the test pile site. A jack is used to press down on the top of the test pile, and the retractable reaction frame is pressed down on the top of the jack. At least one sealing membrane is provided, covering the retractable reaction frame, and the periphery of the sealing membrane is used for insertion into the surface of the test pile site; and, A vacuum pumping assembly is connected to the negative pressure space and is used to extract air from the negative pressure space.

[0015] In the technical solution of the present invention, the retractable reaction frame has a retracted state and an extended state through the extension and retraction of the telescopic rod. When used for testing, the retractable reaction frame only needs to be extended by the extension of the telescopic rod, without the need for assembly, which greatly shortens the installation time of the reaction frame. When used for storage and transportation, the retractable reaction frame only needs to be retracted by the retraction of the telescopic rod, without the need for disassembly, which improves efficiency and reduces the intensity of manual labor. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 A schematic diagram of an embodiment of the retractable reaction frame provided by the present invention (in a retracted state); Figure 2 for Figure 1 A partial structural diagram of the retractable reaction frame; Figure 3 for Figure 1 A top view of part of the retractable reaction frame (in the deployed state); Figure 4 This is a schematic diagram of the vacuum negative pressure loading device provided by the present invention.

[0018] Explanation of icon numbers:

[0019] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0022] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0023] Pile foundations are widely used in building, transportation, municipal, water conservancy, and marine engineering. Meeting design requirements for pile bearing capacity is one of the fundamental conditions for ensuring building safety. However, during the construction of various pile types, the bearing capacity of the piles often fails to meet design requirements due to various reasons, affecting the normal working characteristics of the pile foundation and posing unpredictable potential dangers to the entire building. Therefore, conducting pile bearing capacity assessments and promptly identifying and eliminating problems becomes a crucial step in ensuring the quality of engineering construction.

[0024] Vacuum negative pressure static pile testing is a novel pile testing method. This method involves creating a vacuum within a negative pressure space between the reaction frame and the test pile site, and then using atmospheric pressure to provide the jack loading reaction force. This method offers a straightforward and reliable testing mechanism with minimal safety risks. It eliminates the need for anchor piles, reducing construction time, and facilitates large-scale sampling inspections. However, existing vacuum negative pressure loading devices use reaction frames assembled from multiple trusses, requiring disassembly for transport and reassembly for testing. This assembly process is cumbersome and time-consuming.

[0025] In view of this, the present invention provides a retractable reaction frame 100 for use in a vacuum negative pressure loading device 1000. Figures 1 to 3 This is an embodiment of the retractable reaction frame 100 provided by the present invention.

[0026] Please see Figure 1The retractable reaction frame 100 includes a central support unit 1 and umbrella leaves 2. The central support unit 1 is used to press against the top of the jack 200 in the vacuum negative pressure loading device 1000. It includes a central shaft 11 and multiple telescopic rods 12. The central shaft 11 extends vertically. The multiple telescopic rods 12 are distributed circumferentially around the central shaft 11. Each telescopic rod 12 is set at an angle to the central shaft 11 and one end is connected to the central shaft 11. The umbrella leaves 2 cover the central shaft 11 and are hinged to the top of the central shaft 11. The umbrella leaves 2 are connected to the ends of the multiple telescopic rods 12 away from the central shaft 11. When the telescopic rods 12 extend, the umbrella leaves 2 are forced to unfold outward, and the retractable reaction frame 100 is in the unfolded state. When the telescopic rods 12 retract, the umbrella leaves 2 are forced to retract inward, and the retractable reaction frame 100 is in the retracted state.

[0027] In the technical solution of this invention, the retractable reaction frame 100 has a retracted state and an extended state through the extension and retraction of the telescopic rod 12. When used for testing, the retractable reaction frame 100 only needs to be extended by the extension of the telescopic rod 12, without the need for assembly, which greatly shortens the installation time of the reaction frame. When used for storage and transportation, the retractable reaction frame 100 only needs to be retracted by the retraction of the telescopic rod 12, without the need for disassembly, which improves efficiency and reduces the intensity of manual labor.

[0028] It should be noted that in this invention, the form of the telescopic rod 12 is not limited. The telescopic rod 12 can be manually extended or retracted. Of course, the telescopic rod 12 can also be an electric telescopic rod 12, which can be automatically extended or retracted by a controller. These are all existing technologies and will not be described in detail here.

[0029] For further details, please refer to Figure 2 and Figure 3 The umbrella leaf 2 includes multiple umbrella blades 21 and multiple connecting pieces 22. The multiple umbrella blades 21 are distributed circumferentially along the umbrella leaf 2. The top end of each umbrella blade 21 is hinged to the top end of the central axis 11. Two connecting pieces 22 are connected between any two adjacent umbrella blades 21. One side of each connecting piece 22 is rotatably connected to a connecting piece 22, and the other side of each connecting piece 22 is rotatably connected to an umbrella blade 21. The end of each telescopic rod 12 away from the central axis 11 is connected to the umbrella blade 21 or the connecting piece 22.

[0030] Thus, when the telescopic rod 12 extends or retracts, it drives the umbrella blade 21 or connecting piece 22 connected to it to rotate outward or inward, thereby driving the adjacent umbrella blade 21 or connecting piece 22 to rotate, thereby realizing the unfolding or retraction of the umbrella leaf 2.

[0031] It should be noted that, in the retracted state, two adjacent connecting pieces 22 are folded between the umbrella leaf 21 and the central axis 11 to reduce the area of ​​the umbrella leaf 2. In the unfolded state, two adjacent connecting pieces 22 are located between two adjacent umbrella leaves 21 to expand the area of ​​the umbrella leaf 2.

[0032] It should also be noted that, in this invention, the number of umbrella blades 21 is determined according to the actual required load size. The more umbrella blades 21 are set, the larger the area of ​​the umbrella blades 2, and the greater the load pressure.

[0033] For further details, please refer to Figure 2 and Figure 3 One side of each connecting piece 22 is connected to a connecting piece 22 via a first rotating shaft 3, and the other side of each connecting piece 22 is connected to an umbrella slat 21 via a second rotating shaft 4.

[0034] It should be noted that the number of the first rotating shaft 3 and the number of the second rotating shaft 4 are not limited; there can be one, two, three, etc. For details, please refer to [link / reference needed]. Figure 2 and Figure 3 In one embodiment of the present invention, one side of each connecting piece 22 is connected to a connecting piece 22 via two first rotating shafts 3, and the other side of each connecting piece 22 is connected to an umbrella slat 21 via two second rotating shafts 4.

[0035] Specifically, the umbrella blades 21 and the connecting piece 22 are both made of steel to withstand the load force brought about by the vacuum negative pressure; furthermore, since steel has poor flexibility, in order to allow the umbrella blades 2 to retract, please refer to... Figure 2 The width of the umbrella slat 21 and the width of the connecting piece 22 are respectively set to gradually increase from the end near the center of the umbrella leaf 2 to the end away from the center of the umbrella leaf 2.

[0036] Specifically, a first seal is filled in the gap between each connecting piece 22 and its adjacent connecting piece 22; a second seal is filled in the gap between each connecting piece 22 and its adjacent umbrella piece 21. This improves the sealing performance of the retractable reaction frame 100.

[0037] Furthermore, in one embodiment of the present invention, the first sealing element is a sealing strip and is connected to the connecting piece 22 by structural adhesive; the second sealing element is a sealing strip and is connected to the connecting piece 22 and the umbrella piece 21 by structural adhesive.

[0038] Specifically, in one embodiment of the present invention, the umbrella slat 21 is connected to the top end of the central shaft 11 via a universal joint.

[0039] For details, please refer to Figure 1 and Figure 4 The central support unit 1 further includes a lifting rod 13, which is located at the bottom end of the central shaft 11 and is used to abut against the top of the jack 200. Thus, the overall height of the telescopic reaction frame 100 can be adjusted via the lifting rod 13 to suit different installation conditions.

[0040] It should be noted that in this invention, the form of the lifting rod 13 is not limited. The lifting rod 13 can be manually operated to achieve lifting and lowering. Of course, the lifting rod 13 can also be an electric lifting rod 13 to achieve automatic lifting and lowering. These are all existing technologies and will not be described in detail here.

[0041] This invention also provides a vacuum negative pressure loading device 1000 for pile foundation bearing capacity testing. Please refer to [link / reference]. Figure 4 The system includes a retractable reaction frame 100, a jack 200, at least one sealing membrane 200, and a vacuum assembly. When the retractable reaction frame 100 is in the deployed state, the periphery of the umbrella blades 2 of the retractable reaction frame 100 is used to insert into the surface of the test pile site, forming a negative pressure space with the test pile site. The jack 200 is used to press on the top of the test pile 200, and the retractable reaction frame 100 is pressed on the top of the jack 200. The sealing membrane 200 covers the retractable reaction frame 100, and the periphery of the sealing membrane 200 is used to insert into the surface of the test pile site. The vacuum assembly is connected to the negative pressure space and is used to extract air from the negative pressure space.

[0042] It should be noted that the vacuum negative pressure loading device 1000 adopts the retractable reaction frame 100 as described above. That is, the vacuum negative pressure loading device 1000 has all the technical features of all embodiments of the retractable reaction frame 100, and thus has all the technical effects brought about by all the above technical features. They will not be described in detail here.

[0043] Furthermore, the vacuum negative pressure loading device 1000 also includes an alignment assembly, which further includes a laser emitter and a laser receiver. The laser emitter is detachably mounted on the jack 200 or the test pile 2000 and is located on the center line of the jack 200 or the test pile 2000. The laser emitter is used to emit laser light. The laser receiver is located inside the central axis 11 of the telescopic reaction frame 100 and is located on the center line of the central axis 11. It is used to receive the laser light emitted by the laser emitter.

[0044] Thus, the centerlines of the retractable reaction frame 100, the jack 200, and the test pile 2000 are determined to coincide based on the laser receiver's reception of the laser emitted by the laser transmitter. Specifically, when the laser receiver can receive the laser emitted by the laser transmitter, it is determined that the centerlines of the retractable reaction frame 100, the jack 200, and the test pile 2000 coincide, avoiding eccentric loads during pile bearing capacity testing, which could cause uneven stress on the test pile 2000 and affect the test results. When the laser receiver cannot receive the laser emitted by the laser transmitter, it is determined that the centerlines of the retractable reaction frame 100, the jack 200, and the test pile 2000 do not coincide. In this case, the retractable reaction frame 100 or the test pile 2000 needs to be adjusted until the laser receiver can receive the laser.

[0045] It should be noted that the laser emitter can be detachably installed on the jack 200 or the test pile 2000. When the laser emitter is installed on the jack 200, it checks whether the center line of the jack 200 and the center line of the retractable reaction frame 100 coincide. When the laser emitter is installed on the test pile 2000, it checks whether the center line of the test pile 2000 and the center line of the retractable reaction frame 100 coincide. In other words, it is necessary to change the installation position of the laser emitter to perform the tests separately.

[0046] Specifically, in one embodiment of the present invention, the sealing film 200 is a polyethylene film.

[0047] It should be noted that in this invention, the number of sealing films 200 is not limited. They can be one, two, three, or stacked. Specifically, in one embodiment of this invention, there are two sealing films 200, which are stacked and cover the retractable reaction frame 100.

[0048] Specifically, the vacuum assembly includes a vacuum pump and an air extraction pipe. The vacuum pump is connected to the negative pressure space through the air extraction pipe to extract air from the negative pressure space.

[0049] The present invention also provides a pile foundation bearing capacity testing device, including a vacuum negative pressure loading device 1000. It should be noted that the above-mentioned pile foundation bearing capacity testing device uses the vacuum negative pressure loading device 1000 as described above; that is, the pile foundation bearing capacity testing device has all the technical features of all embodiments of the vacuum negative pressure loading device 1000, and thus possesses all the technical effects brought about by all the above-mentioned technical features, which will not be elaborated further here.

[0050] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A retractable reaction frame for use in a vacuum negative pressure loading device, characterized in that, The retractable reaction frame includes: A central support unit, used to press against the top of the jack in the vacuum negative pressure loading device, includes a central shaft and multiple telescopic rods. The central shaft extends vertically, and the multiple telescopic rods are spaced circumferentially around the central shaft. Each telescopic rod is angled to the central shaft, and one end is connected to the central shaft; and... The umbrella leaf is mounted on the central axis, and its middle part is hinged to the top of the central axis. The umbrella leaf is connected to the end of the plurality of telescopic rods away from the central axis. When the telescopic rod extends, the umbrella leaf is forced to unfold outward, and the telescopic reaction frame is in the unfolded state. When the telescopic rod retracts, the umbrella leaf is forced to retract inward, and the telescopic reaction frame is in the retracted state.

2. The retractable reaction frame as described in claim 1, characterized in that, The umbrella leaf includes: Multiple umbrella blades are spaced apart circumferentially along the umbrella leaf, and the top end of each umbrella blade is hinged to the top end of the central axis; and, Multiple connecting pieces, with two connecting pieces connecting any two adjacent umbrella pieces, and one connecting piece rotatably connected to one side of each connecting piece, and one umbrella piece rotatably connected to the other side of each connecting piece; The end of each telescopic rod away from the central axis is connected to the umbrella flap or the connecting piece.

3. The retractable reaction frame as described in claim 2, characterized in that, One side of each of the connecting pieces is connected to a connecting piece via a first rotating shaft, and the other side of each of the connecting pieces is connected to a slat via a second rotating shaft.

4. The retractable reaction frame as described in claim 2, characterized in that, The umbrella-shaped sheet and the connecting piece are both made of steel. The width of the umbrella leaf and the width of the connecting piece are gradually increased from the end closest to the center of the umbrella leaf to the end furthest from the center of the umbrella leaf.

5. The retractable reaction frame as described in claim 2, characterized in that, The gap between each connecting piece and its adjacent connecting piece is filled with a first seal. The gap between each connecting piece and its adjacent umbrella piece is filled with a second seal.

6. The retractable reaction frame as described in claim 5, characterized in that, The first sealing element is a sealing strip, and it is connected to the connecting piece by structural adhesive; The second sealing element is a sealing strip, and it is connected to the connecting piece and the umbrella piece by structural adhesive.

7. The retractable reaction frame as described in claim 1, characterized in that, The central support unit also includes a lifting rod, which is located at the bottom end of the central axis and is used to abut against the top of the jack.

8. A vacuum negative pressure loading device for testing the bearing capacity of pile foundations, characterized in that, include: As described in any one of claims 1-7, when the retractable reaction frame is in the unfolded state, the periphery of the umbrella blades of the retractable reaction frame is used to insert into the surface of the test pile site to form a negative pressure space with the test pile site. A jack is used to press down on the top of the test pile, and the retractable reaction frame is pressed down on the top of the jack. At least one sealing membrane is provided, covering the retractable reaction frame, and the periphery of the sealing membrane is used for insertion into the surface of the test pile site; and, A vacuum pumping assembly is connected to the negative pressure space and is used to extract air from the negative pressure space.

9. The vacuum negative pressure loading device as described in claim 8, characterized in that, It also includes an alignment component, which further includes: A laser emitter, detachably mounted on the jack or the test pile and located on the centerline of the jack or the test pile, the laser emitter being used to emit a laser; and, A laser receiver is disposed within the central axis of the retractable reaction frame and located on the center line of the central axis, for receiving laser light from the laser emitter.

10. A pile foundation bearing capacity testing device, characterized in that, Includes the vacuum negative pressure loading device as described in claim 8 or 9.

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