Detection device for static load force of self-balancing pile foundation

Abstract

The utility model discloses a self-balancing pile foundation static loading force detection device which comprises a load box, one end of an upper displacement rod and one end of a lower displacement rod are fixedly assembled on the side wall of the load box, a jack is fixedly assembled in the load box, the top of the load box is fixedly connected with one end of an oil pipe, and a steel cage is assembled on the outer side wall of the load box. The other ends of the upper displacement rod and the lower displacement rod are fixedly connected with a displacement sensor, the displacement sensor is fixedly assembled at the bottom of the datum line beam, the displacement sensor is in electric signal connection with data analysis equipment, and the other end of the oil pipe is fixedly connected with a high-pressure oil pump. The load box is redesigned in the device, pipeline distribution in the load box is more reasonable, the connecting process of the displacement sensor and the corresponding pipeline is simplified by optimizing pipeline distribution, meanwhile, the steel cage is also designed in the device, the mode that horn ribs are matched with reinforcing ribs is adopted, and the stability of the device is improved. The stability of connection and fixation between the steel cage and the load box is enhanced, and the protection effect of the steel cage on the load box is enhanced.

Description

Technical Field

[0001] This utility model relates to the field of static load testing technology for pile foundations, and specifically to a device for testing the static load of self-balancing pile foundations. Background Technology

[0002] In recent years, with the acceleration of urbanization in my country, high-rise buildings are becoming increasingly common, and the use of large-tonnage pile foundations for these buildings has become widespread. To ensure the safety of buildings, it is essential to evaluate the reliability of pile foundation quality. The most common and intuitive method for evaluating pile foundation quality is the static load test. However, due to increasingly limited urban space and numerous restrictions on construction sites, static load tests face many limitations and requirements. The traditional surcharge method has the advantages of simple materials and equipment and convenient construction operations, but surcharge preloading requires a certain amount of time, making it suitable for projects with less tight deadlines. Its application is limited, and it requires a large amount of surcharge material, occupies a large area, and the counterweight may affect existing buildings in the vicinity. Furthermore, surcharges placed near construction access roads can affect traffic flow and safe and civilized construction. Therefore, we propose a device for testing the static load capacity of self-balancing pile foundations. Utility Model Content

[0003] The purpose of this invention is to provide a device for detecting the static load of self-balancing pile foundations, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a device for detecting the static load of a self-balancing pile foundation, comprising a load cell, an upper displacement rod and one end of a lower displacement rod fixedly mounted on the side wall of the load cell, a jack fixedly mounted inside the load cell, one end of an oil pipe fixedly connected to the top of the load cell, a steel cage mounted on the outer side wall of the load cell, a displacement sensor fixedly connected to the other end of the upper and lower displacement rods, the displacement sensor fixedly mounted at the bottom of a reference beam, the displacement sensor being electrically connected to a data analysis device, and a high-pressure oil pump fixedly connected to the other end of the oil pipe.

[0005] Preferably, the load box includes a box body, with an upper plate and a lower plate respectively assembled at the upper and lower ends of the box body. The upper displacement rod is fixedly connected to the side wall of the upper plate body, and the lower displacement rod is fixedly connected to the side wall of the lower plate body. A grouting pipe is fixedly connected between the upper plate body and the lower plate body, and the jack is uniformly fixedly assembled inside the box body.

[0006] Preferably, the outer walls of the upper and lower displacement rods are fixedly connected with displacement protection pipes.

[0007] Preferably, the steel cage includes main reinforcing bars, which are uniformly and fixedly connected to the side wall of the load box. Fastening hoops are uniformly and fixedly connected to the outer side wall of the main reinforcing bars, and flared reinforcing bars are fixedly connected between the main reinforcing bars and the load box.

[0008] Preferably, a reinforcing rib is fixedly connected between the main rib and the load box.

[0009] Compared with the prior art, the beneficial effects of this utility model are as follows: A self-balancing pile foundation static load testing device can meet the static load test of pile foundations under various geological conditions. It has the characteristics of safety, accuracy and reliability. The device is simpler and faster to use and operate. It can effectively verify whether the ultimate bearing capacity of the test pile meets the design requirements. The load box in this device has been redesigned to make the internal pipeline distribution more reasonable. By optimizing the pipeline distribution, the connection process between the displacement sensor and its corresponding pipeline is simplified. At the same time, the steel cage in this device has also been designed. The method of using flared ribs and reinforcing ribs to strengthen the stability of the connection and fixation between the steel cage and the load box and enhance the protective effect of the steel cage on the load box. Attached Figure Description

[0010] Figure 1 It is a structural diagram of the present utility model.

[0011] Figure 2 This is a perspective view of the load box of this utility model.

[0012] Figure 3 This is a schematic diagram of the load box of this utility model.

[0013] Figure 4 This is a schematic diagram of the steel cage of this utility model.

[0014] In the diagram: 1. Load cell; 11. Box body; 12. Upper plate; 13. Lower plate; 14. Jack; 15. Oil pipe; 16. Upper displacement rod; 17. Lower displacement rod; 18. Grouting pipe; 19. Displacement protection pipe; 2. Steel cage; 21. Main reinforcement; 22. Fastening hoop; 23. Trumpet reinforcement; 24. Reinforcing rib; 3. Reference beam; 4. Displacement sensor; 5. High-pressure oil pump; 6. Data analysis equipment. Detailed Implementation

[0015] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0016] Please see Figure 1 , Figure 2 , Figure 3 and Figure 4 This utility model provides a technical solution: a device for detecting the static load of a self-balancing pile foundation, including a load cell 1, such as... Figure 2 and Figure 3 As shown, the load box 1 consists of a box body 11, an upper plate 12, and a lower plate 13. The load box 1 is annular. The box body 11 is fixedly equipped with evenly distributed jacks 14, and the top of the upper plate 12 is fixedly equipped with an oil pipe 15 connected to the jacks 14. The side wall of the upper plate 12 is fixedly connected with an axisymmetrically distributed upper displacement rod 16, and the side wall of the lower plate 13 is fixedly connected with an axisymmetrically distributed lower displacement rod 17. A grouting pipe 18 is fixedly installed between the upper plate 12 and the lower plate 13, penetrating its side wall. The grouting pipe 18 is not only used for subsequent grouting into the pile body, but also serves as an acoustic pipe. Sonar equipment can be inserted into it to test the integrity of the interior after the pile body has been initially poured.

[0017] The outer walls of the upper displacement rod 16 and the lower displacement rod 17 are fitted with displacement protection tubes 19. During the process of lowering the load box 1, the upper displacement rod 16 and the lower displacement rod 17 are protected by welding the displacement protection tubes 19 in sequence.

[0018] like Figure 4 As shown, after the load cell 1 is assembled, a steel cage 2 is welded to its exterior for protection. The steel cage 2 is composed of main ribs 21 and fastening hoops 22. The main ribs 21 are evenly welded and fixed to the side walls of the load cell 11. The fastening hoops 22 are welded along the main ribs 21 to secure them. Trumpet ribs 23 are welded and fixed between the main ribs 21 and the load cell 11. The guiding angle of the trumpet ribs 23 is greater than 60°. During the welding process, it is necessary to ensure that the central axis of the steel cage 2 is on the same horizontal line as the center of the load cell 1 before spot welding the trumpet ribs 23. The upper end of the flared reinforcement 23 is welded to the main reinforcement 21, and the lower end is spot-welded to the edge of the inner hole of the load box 1 to ensure that the levelness of the load box 1 is less than 0.3%. The flared reinforcement 23 has two functions: first, when loading, the local pressure on the pile body at the load box 1 is very large, and the flared reinforcement 23 plays a strengthening role; second, the flared reinforcement 23 plays a guiding role, which facilitates the passage of the guide pipe through the load box 1. The main reinforcement 21 is welded and fixed to the upper plate 12 and the lower plate 13 with a reinforcing rib 24. The reinforcing rib 24 is L-shaped, which further enhances the stability of the connection and fixation between the steel cage 2 and the load box 1.

[0019] Displacement sensors 4 are fixedly connected to the top of the upper displacement rod 16 and the lower displacement rod 17 respectively. The displacement sensors 4 are installed inside the reference beam 3, and the oil pipe 15 is connected to the external high-pressure oil pump 5. The high-pressure oil pump 5 is connected to the external oil supply system. Oil can be injected into the load box 1 through the high-pressure oil pump 5, and the force is transmitted upward and downward to the pile body respectively. A pressure gauge is installed in the oil pipe 15 to test the pressure in the load box 1.

[0020] The displacement sensor 4 and the pressure gauge inside the oil pipe 15 are electrically connected to the data analysis device 6. The data analysis device 6 can integrate the data and analyze and calculate the ultimate bearing capacity of the pile foundation in static state.

[0021] Working Principle: During operation, the load cell 1 is first hoisted to the bottom of the pile foundation pit. A steel cage 2 is installed outside the load cell 1 for protection. As the load cell 1 is lowered, the upper displacement rod 16, lower displacement rod 17, grouting pipe 18, and displacement protection pipe 19 are welded and increased in height according to the lowering height. Simultaneously, the steel cage 2 is welded and formed as the load cell 1 is lowered. After the load cell 1 is lowered, concrete is poured into the foundation pit using concrete grouting equipment. Twenty days after pile formation, the reference beam 3 is erected. Displacement sensors 4 are fixedly mounted on the bottom of the reference beam 3. There are four displacement sensors 4. The four displacement sensors 4 are connected to the upper displacement rod 16 and the lower displacement rod 17 respectively. The pressure in the load box 1 can be measured by the pressure gauge connected to the oil pipe 15. The upward and downward displacements of the upper plate 12 and the lower plate 13 in the load box 1 are tested by the displacement sensors 4, and the upward and downward Qs curves are obtained respectively. Then, the data is integrated by the data analysis device 6 to analyze and calculate the ultimate bearing capacity of the pile foundation in static state.

Claims

1. A device for detecting the static load of a self-balancing pile foundation, characterized in that: The load cell includes a load box (1), one end of an upper displacement rod (16) and a lower displacement rod (17) are fixedly mounted on the side wall of the load box (1), a jack (14) is fixedly mounted inside the load box (1), one end of an oil pipe (15) is fixedly connected to the top of the load box (1), a steel cage (2) is mounted on the outer side wall of the load box (1), a displacement sensor (4) is fixedly connected to the other end of the upper displacement rod (16) and the lower displacement rod (17), the displacement sensor (4) is fixedly mounted at the bottom of the reference beam (3), the displacement sensor (4) is electrically connected to a data analysis device (6), and a high-pressure oil pump (5) is fixedly connected to the other end of the oil pipe (15).

2. The device for detecting the static load of a self-balancing pile foundation according to claim 1, characterized in that: The load box (1) includes a box body (11), with an upper plate (12) and a lower plate (13) respectively mounted on the upper and lower ends of the box body (11). The upper displacement rod (16) is fixedly connected to the side wall of the upper plate (12), and the lower displacement rod (17) is fixedly connected to the side wall of the lower plate (13). A grouting pipe (18) is fixedly connected between the upper plate (12) and the lower plate (13). The jack (14) is uniformly fixedly assembled inside the box body (11).

3. The device for detecting the static load of a self-balancing pile foundation according to claim 2, characterized in that: The outer walls of the upper displacement rod (16) and the lower displacement rod (17) are fixedly connected to displacement protection tubes (19).

4. The device for detecting the static load of a self-balancing pile foundation according to claim 1, characterized in that: The steel cage (2) includes main reinforcement bars (21), which are uniformly fixedly connected to the side wall of the load box (1). Fastening hoops (22) are uniformly fixedly connected to the outer side wall of the main reinforcement bars (21), and trumpet reinforcement bars (23) are fixedly connected between the main reinforcement bars (21) and the load box (1).

5. The device for detecting the static load of a self-balancing pile foundation according to claim 4, characterized in that: A reinforcing rib (24) is fixedly connected between the main rib (21) and the load box (1).

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