Offshore platform pile foundation static load test counter-force device

Abstract

The utility model discloses an offshore platform pile foundation static load test counter-force device which comprises a main beam, an auxiliary beam, a fixing frame, a first jack, a second jack, a displacement sensor, a pressure sensor and a control unit. The auxiliary beams comprise the first auxiliary beam and the second auxiliary beam. The top of the main beam is fixedly connected with the center of the bottom of the first auxiliary beam and the center of the bottom of the second auxiliary beam. The first jack is arranged in the vertical direction and fixed to the top of the main pile, and the output end of the first jack makes contact with the center of the bottom of the main beam. The two sets of second jacks are arranged in the horizontal direction and fixed to the bottoms of the two ends of the main beam correspondingly, and the output ends of the two sets of second jacks make contact with the outer sides of the first auxiliary pile and the second auxiliary pile correspondingly. The displacement sensors are arranged on the main pile and the auxiliary pile correspondingly, and the pressure sensors are arranged at the output ends of the first jack and the second jack correspondingly. The counter-force device disclosed by the utility model can be used for carrying out horizontal static thrust and vertical compression resistance static load tests on an offshore pile foundation platform, and is low in cost and simple and convenient to operate.

Description

Technical Field

[0001] The embodiments of the utility model belong to the technical field of pile foundation detection devices, and more specifically, relate to a static load test reaction force device for offshore platform pile foundations. Background Art

[0002] Pile foundations have been widely used in the fields of port, ocean and bridge engineering. The common methods for testing the bearing capacity of pile foundations are high strain method and static load test method. When using the high strain method, in order to ensure the accuracy of the test results, it is usually compared with the static load test method. Therefore, the static load test is the most basic and reliable test method.

[0003] The static load test reaction device for offshore pile foundations must comprehensively consider multiple factors such as structural safety, economic rationality, and ease of operation, and must be able to adapt to the harsh marine environment. Figure 2-3 As shown, there is a certain type of offshore pile foundation platform, which includes a main pile, secondary piles arranged around the main pile foundation as the center, and a work platform erected on the main pile foundation and the secondary piles. The secondary piles are inclined toward the main pile foundation, and the main piles and the secondary piles are connected as a whole through the work platform, which can effectively resist the horizontal impact force brought by the sea waves. However, the pile foundation platform uses multiple pile foundations, and in the marine environment, it is difficult to build a test platform for the reaction force device, which greatly increases the experimental cost.

[0004] Chinese patent CN210342026U discloses a ground-anchored pile foundation static load test device, which relates to the technical field of building electromechanical, and solves the problem of unstable connection between spiral anchor rods and the ground. It includes a bearing platform, a pressure plate abutting the bottom end of the bearing platform, an upper adjustment plate abutting the center position of the bottom end of the pressure plate, a jack abutting the bottom end of the upper adjustment plate, a lower adjustment plate abutting the bottom end of the jack, a column base abutting the bottom end of the lower adjustment plate, and an anchor rod fastened to the bottom end of the pressure plate. The anchor rod includes an anchor rod shell and an anchor rod member. The anchor rod shell is provided with a fixing hole along its height direction, and the anchor rod member is provided with a protrusion that is sleeved with the fixing hole. The anchor rod member is provided with a placement groove for placing the protrusion along its height direction. A spring is fixedly connected to the bottom end of the placement groove, and an end of the spring away from the bottom of the placement groove is fixedly connected to an end of the protrusion close to the bottom of the placement groove. The experimental device in this patent only performs vertical compressive static load tests on a single pile foundation, and anchor rods are required to support the experimental device, which is not suitable for static load tests on offshore pile foundations.

[0005] Therefore, at this stage, there is an urgent need for an offshore platform pile foundation static load test reaction device, which can perform horizontal static push and vertical compressive static load tests on offshore pile foundation platforms with multiple pile foundations. It has low cost, simple and convenient operation, and provides a reliable method for offshore pile foundation static load tests. Summary of the invention

[0006] The static load test device in the prior art can only test a single pile foundation and set anchor rods, and is not suitable for an offshore pile foundation platform with multiple pile foundations. The utility model provides an offshore platform pile foundation static load test reaction force device.

[0007] In order to achieve the above-mentioned purpose, the utility model provides an offshore platform pile foundation static load test reaction device, including a sub-beam, which includes a first sub-beam and a second sub-beam, the two ends of the first sub-beam are respectively fixed to the top of the third sub-pile and the fourth sub-pile through a fixing frame, and the second sub-beam is respectively fixed to the top of the fifth sub-pile and the sixth sub-pile through a fixing frame; a main beam whose top is fixedly connected to the center of the bottom of the first sub-beam and the second sub-beam respectively; a first jack is provided in the vertical direction, which is fixed on the top of the main pile, and the output end is in contact with the center of the bottom of the main beam; second jacks are symmetrically provided at both ends of the bottom of the main beam in the horizontal direction, and the output ends of two groups of the second jacks are respectively in contact with the outer sides of the first sub-pile and the second sub-pile.

[0008] Furthermore, it comprises displacement sensors, and the displacement sensors are provided in multiple groups and are respectively arranged on the main pile and the auxiliary pile.

[0009] Furthermore, it also includes pressure sensors, which are provided in multiple groups and are respectively arranged at the output ends of the first jack and the second jack.

[0010] Furthermore, it also includes a plurality of ground anchor screws respectively fixed on the top of the main pile and the auxiliary pile.

[0011] Furthermore, it also includes a fixed cylinder seat, which is an inverted cylinder structure, the inner diameter of which is respectively adapted to the outer diameter of the top of the main pile and the auxiliary pile and is sleeved on the top of the main pile and the auxiliary pile; the top of the fixed cylinder seat is provided with multiple through holes for the ground anchor screws to pass through.

[0012] Furthermore, the main beam and the auxiliary beam are made of I-beams, wherein both ends of the auxiliary beam are connected to the fixing frame by bolting or welding, and the top of the main beam is connected to the bottom of the auxiliary beam by bolting or welding.

[0013] Furthermore, an arc-shaped plate is fixedly provided on the output end of the second jack, and the arc-shaped plate is matched with the outer circumference of the auxiliary pile.

[0014] In general, the above technical solutions conceived by the utility model can achieve the following beneficial effects compared with the prior art:

[0015] (1) The reaction force device of the utility model is provided with a first auxiliary beam and a second auxiliary beam arranged in parallel, and the two ends of the two auxiliary beams are respectively fixed on the auxiliary piles through a fixing frame, and the top of the main beam is fixedly connected with the center of the bottom of the first auxiliary beam and the second auxiliary beam respectively, so as to form a U-shaped reaction force frame; a first jack is provided on the top of the main pile, and its output end is in contact with the center of the bottom of the main beam; second jacks are symmetrically provided at the bottom of both ends of the main beam along the horizontal direction, and its output end is in contact with the outer side of the auxiliary pile; the first auxiliary beam and the second auxiliary beam form a U-shaped reaction force frame, and the first jack can be used to carry out a static compressive load test of the main pile in the vertical direction, and the second jack can be used to carry out a static push static load test of the auxiliary pile in the horizontal direction; the reaction force device is assembled using the existing structure of the offshore platform pile foundation, and there is no need to set up anchor rods for bearing the experimental device, which is low in cost and simple and convenient to operate.

[0016] (2) The reaction force device of the utility model is provided with pressure sensors at the output ends of the first jack and the second jack, respectively, which can detect and feedback in real time so that the control unit can accurately control the output loading pressure; by installing displacement sensors on the main pile and the auxiliary pile, respectively, the displacement distance of the main pile in the vertical direction and the displacement distance of the auxiliary pile in the horizontal direction can be detected; thereby, the accurate output loading pressure of the reaction force device and the accurate offset value measurement of the offshore platform pile foundation are realized.

[0017] (3) The reaction force device of the utility model fixes the fixing frame and the first jack by using a fixed cylinder seat to pass through the ground anchor screw, thereby avoiding uneven force on the top of the main pile and the auxiliary pile; the second jacks are symmetrically arranged in the horizontal direction at the bottom of both ends of the main beam, and the two groups of second jacks output loading pressure synchronously. The reaction forces applied to the main beam by the two cancel each other out, thereby avoiding the ground anchor screw being subjected to horizontal shear force, and avoiding damage to the pile foundation platform caused by the reaction force device during the pile foundation static load test. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of a static load test reaction device for offshore platform pile foundation in an embodiment of the utility model;

[0019] Figure 2 This is a front view of the offshore platform pile foundation in the embodiment of the utility model;

[0020] Figure 3 A top view of an offshore platform pile foundation in an embodiment of the utility model;

[0021] Figure 4 It is a front view of the static load test reaction force device in the embodiment of the utility model;

[0022] Figure 5 It is a top view of the static load test reaction force device in the embodiment of the utility model.

[0023] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1 - Pile foundation platform, 11 - Main pile, 12 - Auxiliary pile, 121 - First auxiliary pile, 122 - Second auxiliary pile, 123 - Third auxiliary pile, 124 - Fourth auxiliary pile, 125 - Fifth auxiliary pile, 126 - Sixth auxiliary pile, 13 - Working platform, 2 - Main beam, 3 - Auxiliary beam, 31 - First auxiliary beam, 32 - Second auxiliary beam, 4 - Fixed frame. Detailed implementation manners

[0024] In order to make the objectives, technical solutions and advantages of the present utility model clearer and more understandable, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model. In addition, the technical features involved in the various embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0025] As Figure 1-3 shown, the present utility model provides a reaction force device for static load test of offshore platform pile foundations, including a main beam 2, an auxiliary beam 3, a fixed frame 4, a first jack, a second jack, a displacement sensor, a pressure sensor and a control unit. The auxiliary beam 3 includes a first auxiliary beam 31 and a second auxiliary beam 32. Among them, both ends of the first auxiliary beam 31 are respectively fixed to the tops of the third auxiliary pile 123 and the fourth auxiliary pile 124 through the fixed frame 4, and the second auxiliary beam 32 is respectively fixed to the tops of the fifth auxiliary pile 125 and the sixth auxiliary pile 126 through the fixed frame 4. The top of the main beam 2 is fixedly connected to the centers of the bottoms of the first auxiliary beam 31 and the second auxiliary beam 32, and the three are arranged in a cross structure. The first jack is arranged in the vertical direction, fixed to the top of the main pile 11, and the output end contacts the center of the bottom of the main beam 2; the second jack is arranged in the horizontal direction, and there are two groups, respectively fixed to both ends of the bottom of the main beam 2, and the output ends of the two groups of second jacks respectively contact the outsides of the first auxiliary pile 121 and the second auxiliary pile 122. The displacement sensors are respectively arranged on the main pile 11 and the auxiliary piles 12, and the pressure sensors are respectively arranged at the output ends of the first jack and the second jack. The reaction force device of the present utility model can perform horizontal static push and vertical compressive static load tests on the offshore pile foundation platforms of multiple pile foundations, and has low cost, simple and convenient operation.

[0026] As Figure 1-3As shown, in the embodiment of the utility model, the pile foundation platform 1 includes a main pile 11, a plurality of secondary piles 12 arranged around the main pile 11 as the center of the circle, and a work platform 13 erected on the main pile 11 and the secondary piles 12; the secondary pile 12 is inclined toward the main pile foundation, and the main pile 11 and the secondary pile 12 are connected as a whole through the work platform 13, which can effectively resist the horizontal impact force brought by the sea waves. The secondary piles 12 include a first secondary pile 121, a second secondary pile 122, a third secondary pile 123, a fourth secondary pile 124, a fifth secondary pile 125, and a sixth secondary pile 126. In this pile foundation platform 1, the main pile 11 mainly plays the role of bearing vertical loads, and the plurality of secondary piles 12 resist the impact loads in the horizontal direction. Therefore, when performing a static load test, it is necessary to perform a vertical compressive static load test on the main pile 11 and a horizontal static push static load test on the secondary pile 12.

[0027] like Figure 4-5 As shown, in the embodiment of the utility model, when installing the reaction force device, the fixing frame 4 is installed on the third auxiliary pile 123, the fourth auxiliary pile 124, the fifth auxiliary pile 125 and the sixth auxiliary pile 126 respectively. After the installation operation is completed, the two ends of the first auxiliary beam 31 are fixedly connected to the fixing frame 4 set on the top of the third auxiliary pile 123 and the fourth auxiliary pile 124 respectively, and the two ends of the second auxiliary beam 32 are fixedly connected to the fixing frame 4 set on the top of the fifth auxiliary pile 125 and the sixth auxiliary pile 126 respectively. At this time, the first auxiliary beam 31 and the second auxiliary beam 32 are arranged in the horizontal longitudinal direction and are parallel to each other. The main beam 2 is arranged in the horizontal transverse direction, and its top is fixedly connected to the bottom center of the first auxiliary beam 31 and the second auxiliary beam 32 respectively. The first jack is fixed on the top of the main pile 11, and its output end is in contact with the bottom center of the main beam 2. The second jack is symmetrically fixedly installed at the bottom of the two ends of the main beam 2 in the horizontal direction, and the output ends of the two groups of the second jacks are in contact with the outer sides of the first auxiliary pile 121 and the second auxiliary pile 122 respectively. Displacement sensors are installed on the main pile 11 and the auxiliary pile 12 to detect the vertical displacement distance of the main pile 11 and the horizontal displacement distance of the auxiliary pile 12. The pressure sensors are installed on the output ends of the first jack and the second jack to detect the output pressure.

[0028] During the pile foundation static load test, the control unit controls the first jack to apply pressure to the main beam 2, thereby loading the vertical reaction force on the main pile 11. According to the detection information of the pressure sensor provided at the output end of the first jack, the control unit controls the first hydraulic pressure to gradually apply the load until the design ultimate bearing capacity of the main pile 11 is reached, and the displacement distance of the main pile 11 is recorded by the displacement sensor. After completing the vertical compressive static load test of the main pile 11, the load applied by the first jack is removed, and the two groups of second jacks are controlled to synchronously apply pressure to the first auxiliary pile 121 and the second auxiliary pile 122 respectively, until the design ultimate bearing capacity of the auxiliary pile 12 is reached, and the displacement distance of the first auxiliary pile 121 and the second auxiliary pile 122 is recorded; the fixed positions of the first auxiliary beam 31 and the second auxiliary beam 32 are replaced, so that the second jacks sequentially perform horizontal compressive static load tests on the remaining third auxiliary pile 123, the fourth auxiliary pile 124, the fifth auxiliary pile 125, and the sixth auxiliary pile 126, and record the corresponding displacement values. The measured vertical displacement value on the main pile 11 and the horizontal displacement value on the auxiliary pile 12 are compared with the normal offset threshold value to determine whether each pile is normal or not. When conducting a pile foundation static load test, the fixed connection between the workbench 13 and the main pile 11 and the auxiliary pile 12 needs to be released in advance to avoid interfering with the test accuracy.

[0029] In the embodiment of the utility model, when fixing the fixing frame 4 and the first jack, a plurality of ground anchor screws are pre-embedded at the top of the main pile 11 and the auxiliary pile 12, or the ground anchor screws are fixedly connected to the reserved steel bars at the top of the main pile 11 and the auxiliary pile 12 by welding; further, in order to prevent the top of the main pile 11 and the auxiliary pile 12 from being subjected to uneven force and a single ground anchor screw from being subjected to excessive horizontal shear force, the top of the main pile 11 and the auxiliary pile 12 are also respectively provided with a fixing tube The fixed cylinder seat is an inverted cylinder structure, the inner diameter of which is respectively matched with the outer diameter of the top of the main pile 11 and the auxiliary pile 12, and can be respectively sleeved on the top of the main pile 11 and the auxiliary pile 12, and a plurality of through holes are opened on the top of the fixed frame 4 and the first jack for the ground anchor screw to pass through; when fixing the fixed frame 4 and the first jack, the fixed cylinder seat is passed through the ground anchor screw and is respectively sleeved on the top of the main pile 11 and the auxiliary pile 12, and the nut is matched with the ground anchor screw to fix the fixed frame 4 and the first jack on the top of the fixed cylinder seat.

[0030] In an embodiment of the utility model, the main beam 2 and the auxiliary beam 3 are made of I-beams of different types, wherein the two ends of the auxiliary beam 3 are connected to the fixing frame 4 by bolts or welding, and the top of the main beam 2 is connected to the bottom of the auxiliary beam 3 by bolts or welding.

[0031] In the embodiment of the utility model, the loading capacity of the first jack and the second jack shall not be less than 1.2 times of the maximum test load, and the bearing capacity of the main beam 2 and the auxiliary beam 3 shall not be less than 1.2 times of the expected maximum load.

[0032] In the embodiment of the utility model, in order to avoid excessive local loading pressure of the second jack on the auxiliary pile 12 and cause damage to the auxiliary pile 12, an arc plate is fixedly provided at the output end of the second jack. The arc plate is adapted to the outer periphery of the auxiliary pile 12 and transmits the loading pressure of the output end of the second jack to the auxiliary pile 12 by contacting the outer side of the auxiliary pile 12, thereby increasing the force-bearing area and avoiding damage to the auxiliary pile 12.

[0033] The reaction force device of the utility model is provided with a first auxiliary beam 31 and a second auxiliary beam 32 arranged in parallel, and the two ends of the two auxiliary beams are respectively fixed on the auxiliary pile 12 through a fixing frame 4, and the top of the main beam 2 is respectively fixedly connected with the bottom center of the first auxiliary beam 31 and the second auxiliary beam 32 to form a U-shaped reaction force frame; a first jack is provided on the top of the main pile 11, and its output end is in contact with the bottom center of the main beam 2; second jacks are symmetrically provided at the bottom of both ends of the main beam 2 along the horizontal direction, and its output end is in contact with the outer side of the auxiliary pile 12; a U-shaped reaction force frame is formed by the first auxiliary beam 31 and the second auxiliary beam 32, and a compressive static load test of the main pile 11 in the vertical direction can be carried out in conjunction with the first jack, and a static push static load test of the auxiliary pile 12 in the horizontal direction can be carried out in conjunction with the second jack; the reaction force device is assembled using the existing structure of the offshore platform pile foundation, and there is no need to set up anchor rods for bearing the experimental device, and the cost is low and the operation is simple and convenient.

[0034] The reaction force device of the utility model is provided with pressure sensors at the output ends of the first jack and the second jack respectively, which can detect feedback in real time so that the control unit can accurately control the output loading pressure; by installing displacement sensors on the main pile 11 and the auxiliary pile 12 respectively, the displacement distance of the main pile 11 in the vertical direction and the displacement distance of the auxiliary pile 12 in the horizontal direction can be detected; thereby, the accurate output loading pressure of the reaction force device and the accurate offset value measurement of the offshore platform pile foundation are realized.

[0035] The reaction force device of the present invention fixes the fixing frame 4 and the first jack by adopting a fixed cylinder seat to pass the ground anchor screw to avoid uneven force on the top of the main pile 11 and the auxiliary pile 12; the second jacks are symmetrically arranged in the horizontal direction at the bottom of the two ends of the main beam 2, and the two groups of second jacks synchronously output the loading pressure. The reaction forces applied by the two on the main beam 2 offset each other, avoiding the ground anchor screw from being subjected to horizontal shear force, and avoiding damage to the pile foundation platform 1 when the reaction force device performs a pile foundation static load test.

[0036] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A static load test reaction device for offshore platform pile foundation, characterized in that: include: The auxiliary beam (3) comprises a first auxiliary beam (31) and a second auxiliary beam (32), wherein two ends of the first auxiliary beam (31) are respectively fixed to the top of the third auxiliary pile (123) and the fourth auxiliary pile (124) through a fixing frame (4), and the second auxiliary beam (32) is respectively fixed to the top of the fifth auxiliary pile (125) and the sixth auxiliary pile (126) through the fixing frame (4); A main beam (2) whose top is fixedly connected to the center of the bottom of the first auxiliary beam (31) and the second auxiliary beam (32) respectively; A first jack is provided in the vertical direction and is fixed on the top of the main pile (11), with the output end in contact with the center of the bottom of the main beam (2); Second jacks are symmetrically arranged at both ends of the bottom of the main beam (2) in the horizontal direction, and the output ends of two groups of the second jacks are respectively in contact with the outer sides of the first auxiliary pile (121) and the second auxiliary pile (122).

2. The offshore platform pile foundation static load test reaction device according to claim 1, characterized in that: It also includes displacement sensors, which are provided in multiple groups and are respectively arranged on the main pile (11) and the auxiliary pile (12).

3. The offshore platform pile foundation static load test reaction device according to claim 1, characterized in that: It also includes pressure sensors, which are provided in multiple groups and are respectively arranged at the output ends of the first jack and the second jack.

4. An offshore platform pile foundation static load test reaction device according to any one of claims 1 to 3, characterized in that: It also includes a plurality of ground anchor screws respectively fixed on the top of the main pile (11) and the auxiliary pile (12).

5. The offshore platform pile foundation static load test reaction device according to claim 4, characterized in that: It also includes a fixed cylinder seat, which is an inverted cylinder structure, the inner diameter of which is respectively matched with the outer diameter of the top of the main pile (11) and the auxiliary pile (12) and is sleeved on the top of the main pile (11) and the auxiliary pile (12); the top of the fixed cylinder seat is provided with a plurality of through holes for the ground anchor screws to pass through.

6. An offshore platform pile foundation static load test reaction device according to any one of claims 1 to 3, characterized in that: The main beam (2) and the auxiliary beam (3) are made of I-beams, wherein the two ends of the auxiliary beam (3) are connected to the fixing frame (4) by bolting or welding, and the top of the main beam (2) is connected to the bottom of the auxiliary beam (3) by bolting or welding.

7. An offshore platform pile foundation static load test reaction device according to any one of claims 1 to 3, characterized in that: An arc-shaped plate is also fixedly provided at the output end of the second jack, and the arc-shaped plate is matched with the outer circumference of the auxiliary pile (12).

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