A device and method for detecting bearing capacity of caisson foundation base

Abstract

The present application relates to a device and method for detecting the bearing capacity of the base of a caisson foundation, and to the technical field of detecting the bearing capacity of a caisson foundation. The device for detecting the bearing capacity of the base of a caisson foundation comprises: two anchor beams, which are partially pre-buried in the partition walls on both sides of the cross intersection, partially extending out of the upper end surface of the partition wall, and the two are symmetrically arranged relative to the axis of the mud suction pipe at the cross intersection; a pull-back beam, whose two ends are respectively fixed to the top surface of an anchor beam; a force transmission component, one end of which is passed through the mud suction pipe, and the other end of which abuts the center of the pull-back beam; a load box, which is fixed to the end of the force transmission component passed through the mud suction pipe, and the lower end surface of the load box contacts the base in the caisson foundation, and the force transmission component is used to vertically constrain the load box when the load box detects the bearing capacity of the base. The present application not only has a clear force transmission path in the foundation bearing detection process, but is also not limited by the environment, water depth, and foundation soil layer depth, and has high detection accuracy, strong adaptability, and high safety.

Description

Technical Field

[0001] The present application relates to the technical field of caisson foundation bearing capacity detection, and in particular to a caisson foundation base bearing capacity detection device and method. Background Art

[0002] At present, with the development of bridge construction towards wide waters and offshore, there are more and more plans for long-span bridge construction. Caisson foundation has broad application prospects in the field of long-span bridges due to its deep burial depth and strong integrity. Testing the bearing capacity of the caisson foundation base is of great significance for evaluating the service life of long-span bridges. Since the construction area of ​​the caisson foundation of a long-span bridge is usually complex in hydrological conditions, and its burial depth in the soil layer is more than 50m, it is difficult to in-situ test the bearing capacity of the caisson foundation bearing layer. There is currently no economical and fast testing method.

[0003] In the related technology, the flat plate load test adopts a pile load method, which is transmitted to the test soil layer through a force transfer column to carry out a bearing capacity test.

[0004] However, in this test process, the reliability of the test results is difficult to guarantee because the force transmission column is long and easy to deform or even become unstable. In addition, the load volume is large during the load test, and the loading and unloading of the load is huge. The test cycle is long and it takes up a lot of construction space. In addition, the test depth of this method generally does not exceed 20m, and it has strict requirements on the surrounding environmental conditions of the test. It cannot be effectively applied to the foundation bearing capacity detection under deep water and ultra-deep burial conditions. Summary of the invention

[0005] In view of the defects existing in the prior art, the purpose of the present application is to provide a caisson foundation base bearing capacity detection device and method to solve the problem that the bearing capacity detection results in the related technology are of low reliability and cannot be effectively applied to foundation bearing capacity detection under deep water and ultra-deep burial conditions.

[0006] In a first aspect, the present application provides a device for detecting the bearing capacity of a caisson foundation base, wherein the caisson foundation comprises a well wall with an annular cross section, and a plurality of partition walls arranged vertically and horizontally in the well wall, and a mud suction pipe is arranged at the cross intersection of the partition walls, and the detection device comprises:

[0007] Anchor beams, two of which are provided, the two anchor beams are partially embedded in the partition walls on both sides of the cross intersection, partially extend out of the upper end surface of the partition walls, and the two are symmetrically arranged relative to the axis of the mud suction pipe at the cross intersection;

[0008] A tension beam, both ends of which are fixed to the top surface of an anchor beam;

[0009] A force transmission component, one end of which is inserted into the above-mentioned mud suction pipe, and the other end of which abuts against the center of the above-mentioned anti-tension beam;

[0010] The load box is fixed to the end of the force transmission component passing through the mud suction pipe, the lower end surface of the load box is in contact with the base in the caisson foundation, and the force transmission component is used to vertically constrain the load box when the load box detects the bearing capacity of the base.

[0011] In some embodiments, fine sand is filled between the force transmission component and the mud suction pipe.

[0012] In some embodiments, the force transmission assembly includes a push rod, one end of which is passed through the mud suction pipe, and the other end of which abuts against the center of the anti-tension beam through a pad, and the lower end surface of the push rod is fixedly connected to the load box.

[0013] In some embodiments, the load box comprises:

[0014] A mounting plate, the mounting plate being fixed to the lower end surface of the ejector rod;

[0015] An oil cylinder, the oil cylinder is mounted on a side of the mounting plate away from the push rod, and a piston is arranged in the oil cylinder;

[0016] A pressure plate, the pressure plate is connected to the piston and can move with the piston;

[0017] A displacement rod, one end of which is mounted on the pressure plate, and the other end of which passes through the mounting plate and out of the ejector rod;

[0018] The displacement wire has one end passing through the displacement rod and fixed on the pressure plate, and the other end passing through the upper end surface of the displacement rod and connected to the displacement testing mechanism located on the anti-tension beam.

[0019] In some embodiments, the anti-tension beam comprises:

[0020] Main beam;

[0021] There are two connecting parts, which are respectively located on both sides below the main cross beam, and each of the connecting parts is fixedly connected to an anchor beam through a steel pin.

[0022] In some embodiments, the anchor beam comprises:

[0023] A main longitudinal beam, the main longitudinal beam is vertically arranged, and one end of the main longitudinal beam is pre-buried in the partition wall;

[0024] A reinforcing beam horizontally connected to the end of the main longitudinal beam pre-buried in the partition wall;

[0025] A reinforcing member is provided with at least one, and the reinforcing member is transversely connected to the portion of the main longitudinal beam pre-embedded in the partition wall.

[0026] The second aspect of the present application provides a detection method based on the above-mentioned caisson foundation base bearing capacity detection device, which comprises the steps of:

[0027] After the caisson foundation sinks to a certain position, the vertical distance between the inner base of the caisson foundation and the position where the anti-tension beam is to be installed is calculated, and the length of the force transmission assembly is determined according to the vertical distance and the height of the load box;

[0028] Fix the load box at one end of the force transmission assembly, and lower the end fixed with the load box into the sludge suction pipe until the load box contacts the base in the caisson foundation;

[0029] Install a tension beam on the top surface of the anchor beam, and make the center of the lower end surface of the tension beam press against the force transmission component;

[0030] The load box is loaded, and the load box is vertically constrained by the force transmission assembly, so that the pressure plate of the load box produces a downward displacement, and a load-displacement curve that changes with the loaded load is obtained according to the displacement.

[0031] In some embodiments, before the caisson foundation is sunk, the method further includes:

[0032] Pre-embed anchor beams in the partition walls on both sides of the cross intersection in the caisson foundation;

[0033] Concrete pouring is carried out on the above partition wall.

[0034] In some embodiments, after the load box contacts the base in the caisson foundation, the method further comprises:

[0035] Fill fine sand between the force transmission component and the mud suction pipe.

[0036] In some embodiments, after obtaining the load-displacement curve that changes with the applied load according to the above displacement, the method further includes:

[0037] Cut off the portion of the anchor beam that extends beyond the upper end surface of the caisson foundation.

[0038] The beneficial effects of the technical solution provided by this application include:

[0039] The embodiment of the present application provides a device and method for detecting the bearing capacity of the base of a caisson foundation. Since two anchor beams are partially embedded in the partition walls on both sides of the cross intersection and partially extend out of the upper end face of the partition wall to support the anti-tension beam, one end of the force transmission component is inserted into the above-mentioned mud suction pipe, and a load box is fixed on the end face. The other end of the force transmission component abuts the center of the anti-tension beam, and the lower end face of the load box contacts the base in the caisson foundation. Therefore, the mud suction pipe is used as a guide for the force transmission component. When the load box is loaded to detect the bearing capacity of the base in the caisson foundation, the force transmission component can vertically constrain the load box through the anti-tension beam and the anchor beam, so that the loaded load is transmitted downward to obtain the base bearing capacity. The force transmission path of the foundation bearing detection process is clear and is not limited by the environment, water depth, and foundation soil layer depth. The detection accuracy is high, the adaptability is strong, and the safety is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0041] Figure 1 This is a schematic structural diagram of a caisson foundation according to an embodiment of the present application;

[0042] Figure 2 A plan view of a detection device according to an embodiment of the present application;

[0043] Figure 3 A schematic diagram of a partial elevation layout of a detection device according to an embodiment of the present application;

[0044] Figure 4 for Figure 3 AA direction schematic diagram;

[0045] Figure 5 A schematic diagram of the installation of the load box according to an embodiment of the present application;

[0046] Figure 6 Flow chart of the detection method according to an embodiment of the present application.

[0047] Reference numerals:

[0048] 1. Caisson foundation; 11. Suction pipe; 12. Partition wall; 13. Well wall;

[0049] 2. Anchor beam; 21. Main longitudinal beam; 22. Reinforcement beam; 23. Reinforcement member;

[0050] 3. Anti-tension beam; 31. Main cross beam; 32. Connecting part; 33. Steel pin;

[0051] 4. Force transmission assembly; 41. Mandrel; 42. Copy pad; 43. Stiffening plate;

[0052] 5. Load box; 51. Mounting plate; 52. Oil cylinder; 53. Pressure plate; 54. Displacement rod; 55. Displacement wire; 56. Sleeve;

[0053] 6. Fine sand. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0055] The embodiments of the present application provide a caisson foundation base bearing capacity detection device and method, which can solve the problem in the related art that the bearing capacity detection results are of low reliability and cannot be effectively applied to foundation bearing capacity detection under deep water and ultra-deep burial conditions.

[0056] like Figure 1 and Figure 2 As shown, the caisson foundation base bearing capacity detection device of this embodiment is used to detect the base bearing capacity of the super-large and super-deep caisson foundation in bridge engineering. The caisson foundation 1 includes a well wall 13 with a ring-shaped cross section, and a plurality of partition walls 12 arranged vertically and horizontally in the well wall 13. The partition walls 12 divide the space surrounded by the well wall 13 into a plurality of well holes. The plurality of partition walls 12 are arranged vertically and horizontally in a cross-shaped manner, and a mud suction pipe 11 is also provided at the cross intersection of the partition walls 12. A base bearing capacity detection device is provided at some of the mud suction pipes 11. The detection device includes an anchor beam 2, a pull-back beam 3, a force transmission component 4 and a load box 5.

[0057] like Figure 3 and Figure 4 As shown, there are two anchor beams 2, which are partially embedded in the partition walls 12 on both sides of the cross intersection and partially extend out of the upper end surface of the partition wall 12. The two anchor beams 2 are symmetrically arranged relative to the axis of the mud suction pipe 11 at the cross intersection.

[0058] The two ends of the anti-tension beam 3 are respectively fixed to the top surface of an anchor beam 2. One end of the force transmission component 4 is inserted into the above-mentioned mud suction pipe 11, and the other end of the force transmission component 4 abuts against the center of the above-mentioned anti-tension beam 3.

[0059] The load box 5 is fixed to the end of the force transmission component 4 passing through the mud suction pipe 11, and the lower end surface of the load box 5 is in contact with the base in the caisson foundation 1. The force transmission component 4 is used to vertically constrain the load box 5 when the load box 5 detects the bearing capacity of the base in the caisson foundation 1.

[0060] Among them, when the base inside the caisson foundation 1 is disconnected from the mud suction pipe 11, the load box 5 needs to pass through the mud suction pipe 11 and contact the base; when the base inside the caisson foundation 1 is not disconnected from the mud suction pipe 11, the load box 5 is located in the mud suction pipe 11 and contacts the soil in the mud suction pipe 11.

[0061] The detection device of this embodiment has a simple structure, is easy to manufacture, and has a low cost. The mud suction pipe in the caisson foundation is used as a guide for the force transmission component. When the load box is loaded to detect the base bearing capacity in the caisson foundation, the force transmission component can vertically constrain the load box through the anti-tension beam and the anchor beam, so that the loaded load is transmitted downward to obtain the base bearing capacity. The force transmission path of the foundation bearing detection process is clear and is not limited by the environment, water depth, and foundation soil layer depth. It has high detection accuracy, strong adaptability, and high safety.

[0062] Preferably, in order to solve the risk of instability during loading caused by the excessive length of the force transmission component 4, fine sand 6 is filled between the force transmission component 4 and the mud suction pipe 11, and the fine sand 6 can be used as lateral support for the force transmission component 4.

[0063] In this embodiment, the force transmission component 4 includes a push rod 41, one end of which is inserted into the mud suction pipe 11, and the other end of the push rod 41 abuts against the center of the anti-tension beam 3 through a pad 42, and the lower end surface of the push rod 41 is fixedly connected to the load box 5.

[0064] Optionally, the above-mentioned pad 42 is a long steel plate or a long wooden pad, and a stiffening plate 43 is further provided between the outer wall of the above-mentioned top rod 41 and the pad 42, and the stiffening plate 43 can increase the connection strength between the top rod 41 and the pad 42.

[0065] Optionally, the top rod 41 is a steel pipe, the length of the pad 42 is greater than the outer diameter of the top rod 41, and the width of the pad 42 is the same as the width of the tension beam 3, and is smaller than the inner diameter of the top rod 41. Therefore, there is a gap between the top rod 41 and the pad 42 in the vertical direction.

[0066] like Figure 5 As shown, in this embodiment, the load box 5 comprises a mounting plate 51, a cylinder 52, a pressure plate 53, a displacement rod 54 and a displacement wire 55. The cylinder 52 is a jack cylinder.

[0067] The mounting plate 51 is fixed to the lower end surface of the push rod 41. The oil cylinder 52 is mounted on a side of the mounting plate 51 away from the push rod 41, and a piston is disposed in the oil cylinder 52.

[0068] The pressure plate 53 is connected to the end of the piston and can move with the piston. The pressure plate 53 is arranged parallel to the mounting plate 51 .

[0069] One end of the displacement rod 54 is mounted on the pressure plate 53, and the other end of the displacement rod 54 passes through the mounting plate 51 and passes through the top rod 41. Since there is a gap in the vertical direction between the top rod 41 and the pad 42, the end surface of the displacement rod 54 passing through the top rod 41 is located in the gap.

[0070] Optionally, the upper end surface of the displacement rod 54 passing through the top rod 41 is lower than the upper end surface of the pad 42 .

[0071] One end of the displacement wire 55 is inserted into the displacement rod 54 and fixed on the pressure plate 53, and the other end of the displacement wire 55 passes through the upper end surface of the displacement rod 54 and is connected to a displacement testing mechanism, which is located on the anti-tension beam 3. The displacement of the displacement wire 55, that is, the downward displacement of the pressure plate 53, can be obtained through the displacement testing mechanism.

[0072] Optionally, a plurality of positioning rings are provided on the inner wall of the push rod 41, and the portion of the displacement rod 54 that is inserted into the push rod 41 passes through the positioning rings and is limited and fixed by the positioning rings.

[0073] Furthermore, a hollow sleeve 56 is connected to the mounting plate 51 , and the sleeve 56 is sleeved on the end of the push rod 41 to increase the connection stability between the mounting plate 51 and the push rod 41 .

[0074] Optionally, the displacement rod 54 is a hollow sleeve rod, and an annular groove is provided on the pressure plate 53 . One end of the displacement rod 54 is inserted and fixed in the annular groove to increase the connection stability between the displacement rod 54 and the pressure plate 53 .

[0075] In this embodiment, the anti-tension beam 3 includes a main cross beam 31 and a connecting portion 32 .

[0076] There are two connection parts 32 , which are respectively located at two sides below the main beam 31 . Each connection part 32 is fixedly connected to an anchor beam 2 via a steel pin 33 to increase the connection stability between the anti-tension beam 3 and the anchor beam 2 .

[0077] Optionally, the main beam 31 is a double I-beam, the connection part 32 is a connecting steel plate, the two connection parts 32 are parallel to each other and arranged perpendicular to the length direction of the main beam, the two connection parts 32 are respectively inserted at both ends of the main beam 31, and the insertion point is welded and fixed.

[0078] In this embodiment, a stiffening rib may be further provided between the main cross beam 31 and the connecting portion 32 to further enhance the connection strength between the main cross beam 31 and the connecting portion 32 .

[0079] Furthermore, the anchor beam 2 includes a main longitudinal beam 21 and a reinforcing beam 22 .

[0080] The main longitudinal beam 21 is vertically arranged, and one end of the main longitudinal beam 21 is embedded in the partition wall 12 , while the other end of the main longitudinal beam 21 extends out of the upper end surface of the partition wall 12 and is fixedly connected to the connecting portion 32 via a steel pin 33 .

[0081] The reinforcing beam 22 is horizontally connected to the end of the main longitudinal beam 21 embedded in the partition wall 12. Since the reinforcing beam 22 is horizontally arranged, after the partition wall 12 is cast, the reinforcing beam 22 can increase the overall fixing strength of the anchor beam 2 in the partition wall 12.

[0082] Optionally, the portion of the main longitudinal beam 21 embedded in the partition wall 12 is further provided with at least one reinforcement member 23 , which is laterally connected to the main longitudinal beam 21 , that is, the reinforcement member 23 is located between the upper surface of the partition wall 12 and the reinforcement beam 22 .

[0083] In this embodiment, the portion of the main longitudinal beam 21 passing through the partition wall 12 may be provided with reinforcing ribs to further increase the strength of the main longitudinal beam 21 .

[0084] See also Figure 6 As shown, the detection method based on the above-mentioned caisson foundation base bearing capacity detection device in the embodiment of the present application includes the steps of:

[0085] S1. After the caisson foundation 1 sinks to a certain position, the vertical distance between the inner base of the caisson foundation 1 and the position where the tension beam 3 is to be installed is calculated, and the length of the force transmission component 4 is determined according to the above vertical distance and the height of the load box 5.

[0086] The force transmission component 4 includes a push rod 41 and a pad 42. According to the determined length of the force transmission component 4, the push rod 41 can be extended to meet the detection depth requirement.

[0087] S2. Fix the load box 5 at one end of the force transmission assembly 4, and lower the end fixed with the load box 5 into the mud suction pipe 11 until the load box 5 contacts the base in the caisson foundation 1. The lower end surface of the top rod 41 is fixed to the load box 5 by welding.

[0088] S3. Install the tension beam 3 on the top surface of the anchor beam 2, and make the center of the lower end surface of the tension beam 3 press against the force transmission component 4.

[0089] After the top rod 41 and the tension beam 3 are tightened by the cushion 42 , a stiffening plate 43 can be provided between the outer wall of the top rod 41 and the cushion 42 to increase the connection strength between the top rod 41 and the cushion 42 .

[0090] S4. The load box 5 is loaded, and the load box 5 is vertically constrained by the force transmission component 4. The pressure plate of the load box 5 is displaced downward, and a load-displacement curve that changes with the loaded load is obtained according to the displacement.

[0091] When testing the base bearing capacity, the hydraulic jack in the load box 5 is loaded, and the load-displacement curve can be obtained by measuring the downward displacement of the pressure plate at the lower end of the load box 5, and then the actual base bearing capacity can be analyzed.

[0092] In this embodiment, the top rod 41 and the load box 5 are reusable, and repeated tests can be performed by retracting the built-in jack of the load box 5. For the bearing capacity test of the base soil layer at different sinking positions, the pad 42 of different thicknesses can be replaced or the top rod 41 can be extended to adapt to different test depths.

[0093] In this embodiment, in the above step S1, before the caisson foundation 1 is sunk, the following steps are further included:

[0094] Firstly, the anchor beam 2 is embedded in the partition wall 12 on both sides of the cross intersection in the caisson foundation 1 , and the upper end of the anchor beam 2 passes through the partition wall 12 .

[0095] Then, concrete is poured on the partition wall 12 , and while the partition wall 12 is poured, the anchor beam 2 is anchored.

[0096] Preferably, after the load box 5 contacts the base in the caisson foundation 1, the following steps are further included:

[0097] Fine sand 6 is filled between the force transmission component 4 and the mud suction pipe 11 .

[0098] In this embodiment, after obtaining the load-displacement curve that changes with the applied load according to the displacement, the method further includes: cutting off the portion of the anchor beam 2 that exceeds the upper end surface of the caisson foundation 1. Then, normal bridge construction can be carried out.

[0099] The detection method of this embodiment is applicable to the above-mentioned caisson foundation base bearing capacity detection devices. In combination with the structural characteristics of the super-large and super-deep caisson foundation, the mud suction pipes at the cross intersections of the partition walls inside the caisson foundation are used as guides, and the force transmission components connected to the load boxes are inserted into the mud suction pipes. Vertical constraints are achieved through reaction beams and anchor beams. Not only is the force transmission process clear, but it is also not limited by the environment, water depth, and foundation soil layer depth. The detection accuracy is high, the adaptability is strong, and the safety is high.

[0100] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0101] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0102] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A caisson foundation base bearing capacity detection device, the caisson foundation (1) comprising a well wall (13) with an annular cross section, and a plurality of partition walls (12) arranged vertically and horizontally in the well wall (13), wherein a mud suction pipe (11) is arranged at the cross intersection of the partition walls (12), characterized in that: The detection device comprises: Anchor beams (2), two of which are provided, the two anchor beams (2) are partially embedded in the partition walls (12) on both sides of the cross intersection, partially extend out of the upper end surface of the partition wall (12), and the two are symmetrically arranged relative to the axis of the mud suction pipe (11) at the cross intersection; A pull-back beam (3), both ends of which are respectively fixed to the top surface of an anchor beam (2); A force transmission component (4), one end of which is inserted into the mud suction pipe (11) and the other end of which abuts against the center of the anti-tension beam (3); A load box (5) is fixed to the end of the force transmission component (4) passing through the mud suction pipe (11), the lower end surface of the load box (5) is in contact with the base in the caisson foundation (1), and the force transmission component (4) is used to vertically constrain the load box (5) when the load box (5) detects the bearing capacity of the base; Fine sand (6) is filled between the force transmission component (4) and the mud suction pipe (11); The anti-tension beam (3) comprises: Main beam (31); Two connecting parts (32) are provided. The two connecting parts (32) are respectively located on both sides below the main cross beam (31). Each connecting part (32) is fixedly connected to an anchor beam (2) via a steel pin (33).

2. The caisson foundation bearing capacity detection device according to claim 1, characterized in that: The force transmission component (4) comprises a push rod (41), one end of which is inserted into the mud suction pipe (11), and the other end of which abuts against the center of the anti-tension beam (3) through a pad (42), and the lower end surface of the push rod (41) is fixedly connected to the load box (5).

3. The caisson foundation bearing capacity detection device according to claim 2, characterized in that: The load box (5) comprises: A mounting plate (51), wherein the mounting plate (51) is fixed to the lower end surface of the push rod (41); An oil cylinder (52), the oil cylinder (52) being mounted on a side of the mounting plate (51) away from the push rod (41), and a piston being arranged in the oil cylinder (52); A pressure plate (53), the pressure plate (53) being connected to the piston and being movable with the piston; A displacement rod (54), one end of which is mounted on the pressure plate (53), and the other end of which passes through the mounting plate (51) and passes out of the push rod (41); A displacement wire (55) has one end which passes through the displacement rod (54) and is fixed on the pressure plate (53), and the other end which passes through the upper end surface of the displacement rod (54) and is connected to a displacement testing mechanism located on the anti-tension beam (3).

4. The caisson foundation bearing capacity detection device according to claim 1, characterized in that: The anchor beam (2) comprises: A main longitudinal beam (21), wherein the main longitudinal beam (21) is arranged vertically and one end of the main longitudinal beam is pre-buried in the partition wall (12); A reinforcing beam (22) horizontally connected to the end of the main longitudinal beam (21) pre-buried in the partition wall (12); A reinforcing member (23) is provided with at least one reinforcing member (23), and the reinforcing member (23) is transversely connected to the portion of the main longitudinal beam (21) pre-buried in the partition wall (12).

5. A detection method based on the caisson foundation bearing capacity detection device according to claim 3, characterized in that: It includes the steps of: After the caisson foundation (1) sinks to a certain position, the vertical distance between the inner base of the caisson foundation (1) and the position where the anti-tension beam (3) is to be installed is calculated, and the length of the force transmission component (4) is determined according to the vertical distance and the height of the load box (5); Fixing the load box (5) at one end of the force transmission component (4), and lowering the end fixed with the load box (5) into the mud suction pipe (11) until the load box (5) contacts the base in the caisson foundation (1); A pull-back beam (3) is installed on the top surface of the anchor beam (2), and the center of the lower end surface of the pull-back beam (3) is pressed against the force transmission component (4); The load box (5) is loaded, and the load box (5) is vertically constrained by the force transmission component (4), so that the pressure plate of the load box (5) produces a downward displacement, and a load-displacement curve that changes with the loaded load is obtained based on the displacement.

6. The detection method according to claim 5, characterized in that Before the caisson foundation (1) is sunk, the method further comprises: Anchor beams (2) are pre-buried in partition walls (12) on both sides of the cross intersection in the caisson foundation (1); The partition wall (12) is poured with concrete.

7. The detection method according to claim 5, characterized in that: After the load box (5) contacts the base in the caisson foundation (1), the method further comprises: Fine sand (6) is filled between the force transmission component (4) and the mud suction pipe (11).

8. The detection method according to claim 5, characterized in that: After obtaining a load-displacement curve that varies with the applied load according to the displacement, the method further includes: The portion of the anchor beam (2) that protrudes from the upper end surface of the caisson foundation (1) is cut off.

Images