Cast-in-place pile drawing resistance detection device based on soft foundation

Abstract

The utility model provides a soft foundation-based cast-in-place pile anti-drawing force detection device, which comprises a box girder arranged right above a pile to be detected and a jack located on the foundation, a piston rod for supporting the box girder is arranged in the jack, a mounting frame structure for mounting detection equipment is arranged on the foundation, and the box girder is arranged on the mounting frame structure. The detection equipment is used for detecting displacement of a to-be-detected pile in the drawing process, a supporting seat structure is arranged at the bottom of the jack, a platform for supporting the jack is formed at the end of a top plate of the supporting seat structure, and a pressure bearing part abutting against a soft foundation is arranged at the end of a bottom plate of the supporting seat structure. According to the utility model, the supporting seat structure is used for reliably supporting the box girder, thereby ensuring that the box girder does not sink in the detection process, ensuring the accuracy of subsequent displacement detection of the to-be-detected pile, and preventing the problem of detection result deviation caused by sinking of the constructed reaction frame in the detection process.

Description

Technical Field

[0001] The utility model relates to the technical field of building pile foundation construction, in particular to a tensile force detection device for cast-in-place piles based on a weak foundation. Background Art

[0002] During the construction of building pile foundations, a pull-out test is required to test the pull-out resistance of the pile foundation. For hard pile foundations, during the pull-out test, it is only necessary to support the crossbeam used to make the reaction frame above the pile head to be pulled through the column, and then set a jacking mechanism between the reaction frame and the pile head to pull the pile foundation. The pull-out resistance is tested by monitoring the displacement of the pile foundation.

[0003] However, for weak foundations, during the pull-out test, the columns used to make the reaction frames are easily pressed into the weak foundation under the action of the tightening force, which causes the detected pile foundation displacement to be too low, resulting in a large error, which in turn affects the detection quality.

[0004] In addition, currently, the tensile force detection device that usually adopts the reaction frame structure can only adapt to the detection of precast piles, because the pile head of the precast pile has no reserved steel bars, which makes it convenient to use clamps such as clamps to compress the pile head during the detection process, and then use the reaction frame for subsequent detection. However, for cast-in-place piles, there are long steel bars reserved at the top. When constructing the reaction frame structure for tensile force detection, the reserved steel bars will interfere with the reaction frame, which will cause inconvenience in measurement. Utility Model Content

[0005] The utility model aims to provide a bored pile tensile force detection device which combines the steel bars reserved by the bored pile and prevents the problem of detection result deviation caused by the sinking of the reaction frame constructed during the detection process.

[0006] To this end, the utility model adopts the following technical solutions:

[0007] A tensile pull-out force detection device for cast-in-place piles based on a weak foundation comprises a box girder arranged directly above the pile to be detected and a jack located on the foundation, a piston rod for supporting the box girder is arranged in the jack, a mounting frame structure for installing the detection equipment is arranged on the foundation, the detection equipment is used to detect the displacement of the pile to be detected during the pulling process, a support seat structure is arranged at the bottom of the jack, the top plate end of the support seat structure forms a platform for supporting the jack, and the bottom plate end of the support seat structure is arranged with a pressure-bearing part abutting against the weak foundation, and the range of the foundation covered by the pressure-bearing part is larger than the range of the foundation covered by the jack; the pile to be detected is a cast-in-place pile, and a connecting part is arranged on the reserved steel bar of the pile head of the pile to be detected, and the connecting part is directly fixed to the outer surface of the box girder side plate on the side of the box girder.

[0008] Furthermore: symmetrical supporting parts are arranged on the box girder side plates on both sides of the box girder.

[0009] Furthermore: a jack ear seat for lifting is arranged on the outer wall of the jack.

[0010] Furthermore: the jack is connected to the hydraulic pump station through a hydraulic oil pipe.

[0011] Furthermore: a cushion block is arranged between the top of the piston rod and the bottom end surface of the box beam.

[0012] Furthermore: the mounting frame structure includes a column inserted on the top of the weak foundation, and a cross bar is fixed between the adjacent columns on the same side through a clamp, and the cross bar is arranged in the side area of ​​the pile to be detected.

[0013] Furthermore: a displacement sensor is provided in the detection equipment, a probe of the displacement sensor is in contact with the top of the pile to be detected, and the displacement sensor is connected to the displacement acquisition system through a signal line; a magnetic base is provided on the mounting frame structure, and the displacement sensor is installed on the connecting frame of the magnetic base.

[0014] Furthermore: a first lifting ring and a second lifting ring are arranged on both sides of the top end of the box beam, and the first lifting ring and the second lifting ring are connected by a lifting wire rope.

[0015] Furthermore: the support base structure is provided with a box plate between the bottom plate and the top plate thereof.

[0016] Furthermore: a stiffening plate is connected to the outer wall of the box plate, and two ends of the stiffening plate are respectively connected to the bottom plate and the top plate.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] The utility model uses the support seat structure to reliably support the box girder, thereby ensuring that it will not sink during the detection process, ensuring the accuracy of subsequent displacement detection of the pile to be detected, and preventing the detection result deviation problem caused by the sinking of the reaction frame constructed during the detection process; in addition, it can well adapt to the detection of cast-in-place piles, by utilizing the welding fixation between the reserved steel bars and the crossbeams of the cast-in-place piles, avoiding the inconvenience of the traditional prefabricated piles requiring the installation of clamps, and the reserved steel bars are directly welded and fixed symmetrically to the two sides of the box girder, ensuring the symmetry of the force during the subsequent pull-out test, thereby ensuring the stability of the jacking and pulling process. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a three-dimensional structural diagram of the utility model;

[0020] Figure 2For the utility model Figure 1 Partial view of the middle support seat structure.

[0021] Figure 3 For the utility model Figure 1 Partial view of the structure of the sensor mounting bracket.

[0022] The marks in the attached figure are: 1-pile to be tested, 2-magnetic base, 3-displacement sensor, 4-reserved steel bar, 5-signal line, 6-connecting frame, 7-cross bar, 8-hoop, 9-column, 10-support seat structure, 11-bottom plate, 12-reinforced plate, 13-box plate, 14-top plate, 15-jack, 16-hydraulic oil pipe, 17-jack ear seat, 18-piston rod, 19-pad, 20-box girder, 21-first lifting ring, 22-lifting wire rope, 23-box girder side plate, 24-second lifting ring. DETAILED DESCRIPTION

[0023] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0024] like Figure 1-3 As shown, the tensile force detection device for cast-in-place piles based on weak foundations includes a support seat structure 10 for supporting on the top of the weak foundation, two groups of support seat structures 10 are symmetrically arranged on both sides of the pile 1 to be detected, and the support seat structure 10 is used to reliably support the box girder 20, thereby ensuring that it will not sink during the detection process, thereby ensuring the accuracy of subsequent displacement detection of the pile 1 to be detected; a jack 15 for providing a pulling force is arranged on the top of the support seat structure 10, and the end of the top plate 14 of the support seat structure 10 forms a platform for supporting the jack 15, and the end of the bottom plate 11 of the support seat structure 10 is arranged to be close to the weak foundation. The abutted pressure-bearing part has a range of the weak foundation covered by the pressure-bearing part that is larger than the range of the weak foundation covered by the jack 15; the top of the piston rod 18 of the jack 15 supports a box beam 20, and the box beam 20 is arranged directly above the pile 1 to be tested; a connecting part is arranged on the reserved steel bar 4 at the head of the pile 1 to be tested, and the connecting part is directly fixed to the outer surface of the box beam side plate 23 on the side of the box beam 20; at the same time, a mounting frame structure is arranged in the side area of ​​the pile 1 to be tested, and a detection equipment for cooperating with the pile head of the pile 1 to be tested is installed on the mounting frame structure, a pulling force is provided by the jack 15, and the displacement during the pulling process is detected in cooperation with the detection equipment.

[0025] On the basis of the above contents, the tensile pull-out force detection device can well adapt to the tensile pull-out force detection of pile foundation under weak foundation conditions, and prevent the deviation of detection results caused by the sinking of the reaction frame constructed during the detection process; in addition, it can well adapt to the detection of cast-in-place piles, and avoids the inconvenience of traditional prefabricated piles requiring installation of clamps by utilizing the welding fixation between the reserved steel bars 4 of the cast-in-place piles and the crossbeams.

[0026] In this embodiment, the pile 1 to be inspected is a cast-in-place pile. Through the corresponding cast-in-place pile, the reserved steel bar 4 reserved at the top of the cast-in-place pile can be directly used as a connection structure with the box beam 20 in the subsequent inspection process, avoiding the traditional structure that requires a special clamp to clamp and fix the top of the pile 1 to be inspected, simplifying the inspection clamping process and improving the inspection efficiency.

[0027] like Figure 1-2 As shown, the support base structure 10 is provided with a box plate 13 between its bottom plate 11 and top plate 14. A stiffening plate 12 is connected to the outer wall of the box plate 13, and the two ends of the stiffening plate 12 are respectively connected to the bottom plate 11 and the top plate 14. The support base structure 10 can be used to reliably support the jack 15 and the beam during the detection process, and the strength of the support structure is guaranteed, thereby ensuring the stability and reliability of subsequent detection tests.

[0028] like Figure 2 As shown, a jack lug 17 for hoisting is provided on the outer wall of the jack 15, and the jack 15 is connected to the hydraulic pump station through a hydraulic oil pipe 16. The jack 15 can be used to provide a pulling force during the test, and the jack lug 17 can facilitate the subsequent hoisting and movement of the jack 15, and can provide hydraulic power to the jack 15 through the hydraulic pump station during the test.

[0029] In this embodiment, a cushion block 19 is provided between the top of the piston rod 18 and the bottom end surface of the box beam 20. The cushion block 19 increases the contact area between the piston rod 18 and the box beam 20, ensures the uniformity of the receiving, and further ensures the reliability of the jacking process.

[0030] like Figure 1 and 3 As shown, symmetrical force-carrying parts are arranged on the box beam side plates 23 on both sides of the box beam 20, so the multiple reserved steel bars 4 on the pile to be tested 1 can be divided into two groups and fixedly connected to both sides of the box beam 20. And by symmetrically welding and fixing the reserved steel bars 4 directly to both sides of the box beam 20, the symmetry of the force in the subsequent pull-out test process is ensured, thereby ensuring a stable jacking and pulling process.

[0031] like Figure 1As shown, a first lifting ring 21 and a second lifting ring 24 are provided on both sides of the top of the box girder 20. The first lifting ring 21 and the second lifting ring 24 are connected by a lifting wire rope 22. The lifting wire rope 22 facilitates the subsequent lifting and installation of the box girder 20, thereby reducing the difficulty of installing the box girder 20.

[0032] like Figure 3 As shown, the mounting frame structure includes a plurality of columns 9 inserted on the top of the weak foundation, and a cross bar 7 is fixed between the adjacent columns 9 on the same side through a clamp 8, and the cross bar 7 is arranged in the side area of ​​the pile 1 to be detected. Therefore, the mounting frame structure can conveniently fix and install the displacement sensor 3, and the installed displacement sensor 3 will not be disturbed, ensuring the reliable measurement and detection accuracy of the displacement of the pile 1 to be detected in the subsequent pulling process.

[0033] like Figure 3 As shown, the detection device is provided with a displacement sensor 3, and there are a plurality of displacement sensors 3. Each group of displacement sensors 3 is respectively mounted on a connecting frame 6 of a magnetic base 2, and a probe of the displacement sensor 3 is in contact with the top of the pile 1 to be detected; the displacement sensor 3 is connected to the displacement acquisition system via a signal line 5.

[0034] The reliability of the detection can be ensured by detecting the displacement amount by multiple groups of displacement sensors 3 at the same time. The magnetic base 2 is connected to the crossbar 7, and the fixing and installation process of the displacement sensor 3 can be simplified through the magnetic base 2.

[0035] See also Figure 1-3 When the cast-in-place pile tensile force detection device performs tensile force detection on the pile 1 to be detected, the specific contents are as follows:

[0036] When it is necessary to carry out a tensile test on the cast-in-place piles with a weak foundation, first, arrange the support seat structure 10, and symmetrically set the two groups of support seat structures 10 on both sides of the pile 1 to be tested. Use a large crane to hoist the jack 15 to the top of the support seat structure 10, and then use a large crane to hoist the box girder 20 to the top of the jack 15, and directly weld and fix the reserved steel bars 4 on the top of the pile 1 to be tested to the two sides of the box girder 20 symmetrically.

[0037] Then, a mounting frame structure is arranged outside the pile 1 to be detected, and a displacement sensor 3 is arranged and installed on the mounting frame structure through a magnetic base 2, so that the probe of the displacement sensor 3 contacts the top of the pile 1 to be detected.

[0038] Finally, the jack 15 is started and the box girder 20 is lifted by the jack 15. During the lifting process of the box girder 20, the pile 1 to be tested will be pulled synchronously. During the pulling process of the pile 1 to be tested, the displacement sensor 3 will detect the displacement of the pile 1 to be tested, and then the anti-pulling performance of the pile 1 to be tested will be tested based on the lifting force and the displacement.

[0039] The above embodiment is only a preferred technical solution of the present invention. Those skilled in the art should understand that the technical solutions or parameters in the embodiments can be modified or replaced without departing from the principle and essence of the present invention, and all should be included in the protection scope of the present invention.

Claims

1. A tensile force detection device for cast-in-place piles based on a weak foundation, comprising a box beam (20) arranged directly above a pile to be detected (1), and a jack (15) located on the foundation, wherein a piston rod (18) supporting the box beam (20) is arranged in the jack (15), and a mounting frame structure for mounting a detection device is arranged on the foundation, wherein the detection device is used to detect the displacement of the pile to be detected (1) during the pulling process, and is characterized in that: A support seat structure (10) is provided at the bottom of the jack (15); the end of the top plate (14) of the support seat structure (10) forms a platform for supporting the jack (15); and the end of the bottom plate (11) of the support seat structure (10) is provided with a pressure-bearing portion that abuts against a weak foundation; The pile to be tested (1) is a cast-in-place pile, and a connection portion is provided on the reserved steel bar (4) at the pile head of the pile to be tested (1), and the connection portion is directly fixedly connected to the outer surface of the box beam side plate (23) on the side of the box beam (20).

2. The device for detecting the tensile strength of cast-in-place piles based on a weak foundation according to claim 1 is characterized in that: Symmetrical supporting parts are arranged on the box beam side plates (23) on both sides of the box beam (20).

3. The device for detecting the tensile strength of cast-in-place piles based on a weak foundation according to claim 1 is characterized in that: A jack ear seat (17) for lifting is arranged on the outer wall of the jack (15).

4. The device for detecting the tensile strength of cast-in-place piles based on a weak foundation according to claim 1 is characterized in that: The jack (15) is connected to the hydraulic pump station via a hydraulic oil pipe (16).

5. The device for detecting the tensile strength of cast-in-place piles based on a weak foundation according to claim 1 is characterized in that: A cushion block (19) is provided between the top of the piston rod (18) and the bottom end surface of the box beam (20).

6. The device for detecting the tensile strength of cast-in-place piles based on a weak foundation according to claim 1 is characterized in that: The mounting frame structure comprises a column (9) inserted on the top of a weak foundation, and a crossbar (7) is fixed between the columns (9) adjacent to each other on the same side via a clamp (8), and the crossbar (7) is arranged in a side area of ​​the pile (1) to be detected.

7. The tensile strength detection device for cast-in-place piles based on weak foundation according to claim 1 or 6, characterized in that: The detection device is provided with a displacement sensor (3), a probe of the displacement sensor (3) is in contact with the top of the pile (1) to be detected, and the displacement sensor (3) is connected to the displacement acquisition system via a signal line (5); a magnetic base (2) is provided on the mounting frame structure, and the displacement sensor (3) is mounted on a connecting frame (6) of the magnetic base (2).

8. The device for detecting the tensile strength of cast-in-place piles based on a weak foundation according to claim 1 is characterized in that: A first lifting ring (21) and a second lifting ring (24) are arranged on both sides of the top end of the box beam (20), and the first lifting ring (21) and the second lifting ring (24) are connected via a lifting wire rope (22).

9. The device for detecting the tensile strength of cast-in-place piles based on a weak foundation according to claim 1 is characterized in that: The support seat structure (10) is provided with a box plate (13) between its bottom plate (11) and top plate (14).

10. The device for detecting the tensile strength of cast-in-place piles based on a weak foundation according to claim 9, characterized in that: A reinforcing plate (12) is connected to the outer wall of the box body plate (13), and two ends of the reinforcing plate (12) are respectively connected to the bottom plate (11) and the top plate (14).

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