Photovoltaic pile static load test device

Abstract

The utility model discloses a photovoltaic cast -in -place pile static load test device relates to cast -in -place pile test technical field, including photovoltaic cast -in -place pile body and device bottom plate, and steel bar support column is penetrated in device bottom plate, just device bottom plate is located photovoltaic cast -in -place pile body top, be provided with the lifting plate on the device bottom plate, and lifting plate stress constitutes micro - distance lifting structure, the inside through - going setting of lifting plate is provided with the perfusion pipe, be provided with three clamping blocks below lifting plate, and clamping block constitutes the clamping structure to photovoltaic cast -in -place pile body upper end edge, be provided with displacement sensor to photovoltaic cast -in -place pile body front side. This photovoltaic cast -in -place pile static load test device has solved the problem that traditional test device is uneven, and loading eccentric, and the pile top edge stress deviation reduces, and the measurement precision improves, is applicable to the static load test of photovoltaic cast -in -place pile, ensures the accuracy and reliability of single - pile vertical compressive bearing capacity test data.

Description

Technical Field

[0001] This utility model relates to the field of cast-in-place pile testing technology, specifically a static load testing device for photovoltaic cast-in-place piles. Background Technology

[0002] Static load testing of photovoltaic (PV) cast-in-place piles is a key testing method for verifying the bearing capacity of PV support foundations. By applying a vertical static load to the top of the pile, the settlement and stress performance of the pile are observed. During the test, a reaction frame system is used to apply the load in stages, and displacement sensors monitor the settlement at the top of the pile in real time. The next load stage can only be applied when the settlement rate is <0.01 mm / h and continues for 2 hours. This test is suitable for reinforced concrete cast-in-place piles for PV arrays and can accurately determine the ultimate vertical compressive bearing capacity of a single pile, providing data support for PV support foundation design. However, existing static load testing devices for PV cast-in-place piles still have certain problems in use:

[0003] For example, the technical solution of the random selection pile compression static load test device for cast-in-place piles with application number 202221786027.4 is as follows: it includes a casing, which is sleeved and installed on the upper part of the reinforced concrete cast-in-place pile; grout is poured into the upper part of the casing and filled with the reinforced concrete cast-in-place pile; and a dowel bar is vertically installed on the upper end of the casing, with the upper end of the dowel bar extending to the ground for stacking the test load counterweight. However, the uneven force distribution of the existing device seriously affects the accuracy and reliability of the test data. Traditional tests mostly use the surcharge method or the anchor pile method. The surcharge method relies on the superposition of heavy objects such as sandbags and concrete blocks for loading. Because it is difficult to achieve uniform load distribution by manual stacking, the local stress at the pile top is deviated, causing the pile body to be eccentrically stressed, and the measured settlement data has an error compared with the true value.

[0004] In view of this, in-depth research was conducted on the above issues, which led to the creation of this case.

[0005] To address the aforementioned issues, an innovative design was developed based on the existing experimental setup. Utility Model Content

[0006] The purpose of this invention is to provide a static load testing device for photovoltaic cast-in-place piles to solve the problem mentioned in the background art where uneven stress leads to deviations in local stress at the pile top.

[0007] To achieve the above objectives, this utility model provides the following technical solution:

[0008] A static load testing device for photovoltaic (PV) cast-in-place piles includes a PV cast-in-place pile body and a device base plate. A grouting base is provided at the bottom of the PV cast-in-place pile body, located below the ground level. A reinforced steel support column is cast and fixedly installed above the grouting base. The reinforced steel support column penetrates the device base plate, which is located at the top of the PV cast-in-place pile body. A lifting plate is provided above the device base plate, and the lifting plate forms a micro-distance lifting structure under stress. A grouting pipe is installed inside the lifting plate. Three clamping blocks are provided below the lifting plate, forming a clamping structure on the upper edge of the PV cast-in-place pile body. A displacement sensor is provided on the front side of the PV cast-in-place pile body.

[0009] Preferably, a sliding sleeve is fixedly installed at the bottom of the lifting plate, and the sliding sleeve is slidably connected to the outside of the injection pipe.

[0010] Using the above technical solution, the sliding sleeve is slidably connected to the outside of the grouting pipe, so that the lifting plate can be raised and lowered along the grouting pipe by a small distance. This ensures that the load is evenly transferred to the top of the photovoltaic grouting pile body during loading, avoids local stress deviation caused by lifting jamming, and reduces load transfer error.

[0011] Preferably, a lifting head is fixedly installed above the lifting plate, and an injection port is opened at the top of the lifting head, with the injection pipe passing through the bottom of the lifting head.

[0012] Using the above technical solution, the injection port at the top of the hoisting head is connected to the injection pipe, which facilitates the injection of concrete slurry into the photovoltaic injection pile body. At the same time, the hoisting head can assist in lifting the lifting plate, improving the installation efficiency of the device.

[0013] Preferably, the bottom of the lifting plate is hinged with three first connecting rods, and the angle between two adjacent first connecting rods and the center of the lifting plate is 120°.

[0014] Using the above technical solution, the three first connecting rods are distributed at a 120° angle at the bottom of the lifting plate to form a symmetrical force transmission structure. When the lifting plate is pressed down by the load, the force can be evenly transmitted to the three clamping blocks, reducing the force deviation at the edge of the pile top and solving the eccentricity problem of traditional single-point loading.

[0015] Preferably, a second link is hinged below the first link, and an H-shaped frame is fixedly connected to the hinge post of the second link.

[0016] Using the above technical solution, the second connecting rod is hinged to the H-shaped frame, which converts the vertical force of the first connecting rod into a horizontal clamping force. Combined with the clamping block with the action of the torsion spring, it can adaptively fit the edge of the pile body, and improve the uniformity of the clamping force.

[0017] Preferably, a support frame is fixedly installed on the outer edge of the base plate of the device, and the lower part of the H-shaped frame is hinged to the support frame, and a clamping block is hinged inside the lower part of the H-shaped frame by a torsion spring.

[0018] By adopting the above technical solution, the support frame is fixed to the bottom plate of the device, providing a hinge fulcrum for the H-shaped frame, so that the clamping block remains stable during loading, avoiding displacement monitoring errors caused by support swaying, and improving the measurement accuracy of the displacement sensor.

[0019] Preferably, a universal ball joint support is fixedly installed above the lifting plate, and a load-bearing beam is fixedly installed above the universal ball joint support, with a jack installed at the bottom of the load-bearing beam.

[0020] Using the above technical solution, the universal ball joint support connects the load-bearing beam and the lifting plate, allowing for a slight angular offset when the jack is loaded, adapting to different loading directions, ensuring that the load acts vertically on the pile top, and reducing the load verticality deviation.

[0021] Compared with the prior art, the beneficial effects of this utility model are: the photovoltaic cast-in-place pile static load test device,

[0022] 1. Symmetrical clamping and uniform loading design: The three clamping blocks are linked with the H-shaped frame through the first and second connecting rods distributed at 120°, forming a three-way symmetrical clamping structure. When the jack on the load-bearing beam applies a load, the force is evenly transmitted to the lifting plate through the universal ball joint support, and then the connecting rod system acts synchronously on the clamping blocks, which reduces the force deviation at each point on the pile top edge and improves the loading uniformity compared with the traditional surcharge method.

[0023] 2. Precise displacement monitoring and adaptive adjustment: The sliding fit between the sliding sleeve and the grouting pipe ensures that the lifting plate rises and falls smoothly. The displacement sensor monitors the settlement of the pile top in real time. The clamping block adaptively fits the pile body through the torsion spring. Even if there is a deviation in the pile diameter, it can still ensure uniform clamping force and avoid test data distortion caused by poor contact. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the front structure of this utility model;

[0025] Figure 2 This is a schematic diagram of the main structure of the photovoltaic cast-in-place pile of this utility model;

[0026] Figure 3 This is a schematic diagram of the base plate structure of the device of this utility model;

[0027] Figure 4 This is a schematic diagram of the clamping block structure of this utility model;

[0028] Figure 5 This is a front view of Embodiment 2 of the present invention.

[0029] In the diagram: 1. Photovoltaic cast-in-place pile body; 2. Cast-in-place base; 3. Reinforcing steel support column; 4. Device base plate; 401. Support frame; 5. Cast-in-place pipe; 6. Lifting head; 7. Cast-in-place port; 8. Lifting plate; 9. Sliding sleeve; 10. First connecting rod; 11. Second connecting rod; 12. H-shaped frame; 13. Clamping block; 14. Universal ball joint support; 15. Load-bearing beam; 16. Displacement sensor. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0031] Example 1

[0032] Please see Figure 1-4 This utility model provides a technical solution:

[0033] A static load test device for photovoltaic cast-in-place piles includes a photovoltaic cast-in-place pile body 1 and a device base plate 4. A grouting base 2 is provided at the bottom of the photovoltaic cast-in-place pile body 1, and the grouting base 2 is located below the ground level. A steel reinforcement support column 3 is cast and fixedly installed on the grouting base 2. The steel reinforcement support column 3 passes through the device base plate 4, and the device base plate 4 is located at the top of the photovoltaic cast-in-place pile body 1. A lifting plate 8 is provided above the device base plate 4, and the lifting plate 8 forms a micro-distance lifting structure under force. A grouting pipe 5 is provided inside the lifting plate 8. Three clamping blocks 13 are provided below the lifting plate 8, and the clamping blocks 13 form a clamping structure on the upper edge of the photovoltaic cast-in-place pile body 1. A displacement sensor 16 is provided on the front side of the photovoltaic cast-in-place pile body 1.

[0034] A sliding sleeve 9 is fixedly installed at the bottom of the lifting plate 8, and the sliding sleeve 9 is slidably connected to the outside of the grouting pipe 5. A hoisting head 6 is fixedly installed above the lifting plate 8, and a grouting port 7 is opened at the top of the hoisting head 6. The grouting pipe 5 passes through the bottom of the hoisting head 6. The sliding sleeve 9 is slidably connected to the outside of the grouting pipe 5, so that the lifting plate 8 can be raised and lowered along the grouting pipe 5 by a small distance. This ensures that the load is evenly transferred to the top of the photovoltaic grouting pile body 1 during loading, avoids local stress deviation caused by lifting and lowering jams, and reduces load transfer error. The grouting port 7 at the top of the hoisting head 6 is connected to the grouting pipe 5, which facilitates the injection of concrete slurry into the photovoltaic grouting pile body 1. At the same time, the hoisting head 6 can assist in lifting the lifting plate 8, improving the installation efficiency of the device.

[0035] Three first connecting rods 10 are hinged to the bottom of the lifting plate 8, and the angle between any two adjacent first connecting rods 10 and the center of the lifting plate 8 is 120°. A second connecting rod 11 is hinged below the first connecting rods 10, and an H-shaped frame 12 is fixedly connected to the hinge post of the second connecting rod 11. A support frame 401 is fixedly installed on the outer edge of the device base plate 4, and the H-shaped frame 12 is hinged to the support frame 401 below. A clamping block 13 is hinged to the interior of the H-shaped frame 12 via a torsion spring. The three first connecting rods 10 are distributed at a 120° angle at the bottom of the lifting plate 8, forming a symmetrical force transmission structure. When the lifting plate 8 is subjected to… When the load is applied, the force can be evenly transmitted to the three clamping blocks 13, reducing the force deviation at the edge of the pile top and solving the eccentricity problem of traditional single-point loading. The second connecting rod 11 is hinged to the H-shaped frame 12, converting the vertical force of the first connecting rod 10 into a horizontal clamping force. The clamping blocks 13, which work in conjunction with the torsion spring, can adaptively fit the edge of the pile, improving the uniformity of the clamping force. The support frame 401 is fixed to the base plate 4 of the device, providing a hinge fulcrum for the H-shaped frame 12, keeping the clamping blocks 13 stable during loading and avoiding displacement monitoring errors caused by support swaying. The measurement accuracy of the displacement sensor 16 is improved.

[0036] Example 2

[0037] Please see Figure 5 This utility model provides a technical solution:

[0038] A universal ball joint support 14 is fixedly installed above the lifting plate 8, and a load-bearing beam 15 is fixedly installed above the universal ball joint support 14. A jack is installed at the bottom of the load-bearing beam 15. The universal ball joint support 14 connects the load-bearing beam 15 and the lifting plate 8, allowing a small angular offset when the jack is loaded, adapting to different loading directions, ensuring that the load acts vertically on the pile top, and reducing the load verticality deviation.

[0039] Working principle:

[0040] In use, the device base plate 4 is fitted onto the steel support column 3. Grout is poured into the photovoltaic injection pile body 1 through the injection pipe 5. After curing, the hoisting head 6 lifts the lifting plate 8, so that the sliding sleeve 9 is fitted onto the outside of the injection pipe 5. The three first connecting rods 10 rotate, driving the second connecting rod 11 to rotate. The lower end of the second connecting rod 11 is hinged to the H-shaped frame 12, which rotates. The H-shaped frame 12 drives the clamping block 13 to fit against the edge of the pile body through a torsion spring. The clamping block 13 is made of silicone rubber. The optional load-bearing beam 15 is fixed to the lifting plate 8 through the universal ball joint support 14. The jack is placed at the bottom of the load-bearing beam 15, and the load is applied in stages. When the jack is applied, the force is transmitted through the universal ball joint support 14. 4. The load is transferred to the lifting plate 8, which descends slightly along the grouting pipe 5, causing the first connecting rod 10 to press down the second connecting rod 11, making the H-shaped frame 12 rotate towards the center of the pile. The clamping block 13 clamps the edge of the pile top through the torsion spring, forming a three-dimensional uniform pressure. At the same time, the displacement sensor 16 monitors the settlement of the pile top in real time. When the settlement rate is <0.01mm / h and lasts for 2 hours, the next level of load is applied. The displacement sensor 16 is fixed to the front side of the pile and collects the vertical displacement data of the pile top in real time. The data is transmitted to the external controller through the data line. The controller records the settlement under each level of load. When the settlement reaches the specification requirements, it automatically prompts to load or stop, ensuring the accuracy and standardization of the test data.

[0041] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0042] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A static load test device for photovoltaic cast-in-place piles, comprising a photovoltaic cast-in-place pile body (1) and a device base plate (4), wherein a casting base (2) is provided at the bottom of the photovoltaic cast-in-place pile body (1), and the casting base (2) is located below the ground level, and a steel reinforcement support column (3) is cast and fixedly installed above the casting base (2), the steel reinforcement support column (3) penetrates through the device base plate (4), and the device base plate (4) is located at the top of the photovoltaic cast-in-place pile body (1), characterized in that: A lifting plate (8) is provided above the base plate (4) of the device, and the lifting plate (8) forms a micro-distance lifting structure under force. A grouting pipe (5) is provided inside the lifting plate (8). Three clamping blocks (13) are provided below the lifting plate (8), and the clamping blocks (13) form a clamping structure on the upper edge of the photovoltaic grouting pile body (1). A displacement sensor (16) is provided on the front side of the photovoltaic grouting pile body (1).

2. The photovoltaic cast-in-place pile static load test device according to claim 1, characterized in that: The bottom of the lifting plate (8) is fixedly installed with a sliding sleeve (9), and the sliding sleeve (9) is slidably connected to the outside of the injection pipe (5).

3. The photovoltaic cast-in-place pile static load test device according to claim 2, characterized in that: A lifting head (6) is fixedly installed above the lifting plate (8), and an injection port (7) is opened at the top of the lifting head (6), and an injection pipe (5) passes through the bottom of the lifting head (6).

4. The photovoltaic cast-in-place pile static load test device according to claim 1, characterized in that: The bottom of the lifting plate (8) is hinged with three first connecting rods (10), and the angle between two adjacent first connecting rods (10) and the center of the lifting plate (8) is 120°.

5. The photovoltaic cast-in-place pile static load test device according to claim 4, characterized in that: A second link (11) is hinged below the first link (10), and an H-shaped frame (12) is fixedly connected to the hinge post of the second link (11).

6. The photovoltaic cast-in-place pile static load test device according to claim 5, characterized in that: A support frame (401) is fixedly installed on the outer edge of the base plate (4) of the device, and the H-shaped frame (12) is hinged to the support frame (401) below, and a clamping block (13) is hinged to the inside of the H-shaped frame (12) by a torsion spring.

7. The photovoltaic cast-in-place pile static load test device according to claim 1, characterized in that: A universal ball joint support (14) is fixedly installed above the lifting plate (8), and a load-bearing beam (15) is fixedly installed above the universal ball joint support (14), and a jack is installed at the bottom of the load-bearing beam (15).

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