CN220847733U - Single pile static load testing device - Google Patents

Abstract

The utility model discloses a single pile static load testing device, belongs to the technical field of constructional engineering, and solves the technical problems of difficult adjustment of the levelness of a cross beam, a large number of anchor piles, high testing cost and long testing time in the existing static load testing device. The device comprises a test pile, an anchor pile, a cross beam, a loading device, a supporting component and an anchor connecting device. Wherein, supporting component and crossbeam fixed connection realize the regulation of crossbeam levelness through the height of adjusting the bracing piece in the supporting component, secondly, anchor connecting device contains pre-buried steel strand wires and anti-locking device in the steel strand wires cage, utilizes the high tensile strength of steel strand wires to provide the counter-force for the test stake, has reduced anchor stake quantity, reduces test cost and shortens test time, anti-locking device contain locating piece and clamp block, through the conical surface interact of locating piece and clamp block, inwards shrink hugs the steel strand wires, the steel strand wires can produce the effect of pulling more tight more.

Description

Single pile static load testing device

Technical Field

The utility model relates to the technical field of constructional engineering, in particular to a single pile static load testing device.

Background

The static load test is a test for testing the bearing capacity of a building foundation pile, namely, vertical pressure is applied to the top of a test pile step by step, pile top settlement of a single pile under different load effects is measured, a static load test auxiliary curve is obtained, and parameters such as a vertical compression bearing capacity characteristic value of the single pile are deduced according to the curve. The utility model of China of the prior publication No. CN 217105249U discloses a detection device for static load test of an anchor pile method, the device jacks up a main beam by using a loading device, the main beam transmits stress to an auxiliary beam, the auxiliary beam is connected with anchor bars embedded in anchor piles by anchor hoop assemblies, a plurality of anchor piles distributed around the test piles provide counter-pulling force, the test piles are subjected to graded loading by controlling the size of applied load of the loading device, and the detection of bearing capacity of the foundation piles is realized.

1. In the levelness adjustment process of the main beam and the auxiliary beam, the levelness adjustment of the main beam and the auxiliary beam is difficult due to the mutual interference of a plurality of fastening points on the auxiliary beam and the mutual interference between the main beam and the auxiliary beam, so that even stress of a threaded rod in the anchor hoop assembly and anchor bars in the anchor piles during testing cannot be ensured, unbalanced load or overload is caused, and the danger that the threaded rod and the reinforcing steel bars are easily broken exists;

2. The levelness adjustment of the main beam and the auxiliary beam can be carried out only in a hanging state or under the condition of using other auxiliary tools, so that potential safety hazards exist or other auxiliary tools are needed to be added;

3. The beam combination structure of the main beam and the auxiliary beam is adopted to be connected with anchor bars in a plurality of anchor piles arranged around the test pile, the test pile is provided with reverse tension, the number of the anchor piles is large, the test cost is high, the test time is long, on the other hand, the number of the beams is large, the structure is complex, and the cost of manufacturing, transporting, testing and the like is increased.

With the advent of a large number of super high-rise buildings, the ultimate bearing capacity of the single foundation pile adopted is larger and larger, so that the defects existing in the anchor pile method static load testing device in the prior art are more remarkable, and in order to solve the technical problems, the single pile static load testing device is needed to overcome the defects in the prior art.

Disclosure of utility model

The utility model aims to provide a single pile static load testing device to solve the technical problems that the levelness of a cross beam is difficult to adjust, potential safety hazards exist, the number of anchor piles is large, the testing cost is high and the testing time is long.

In order to achieve the above purpose, the present utility model provides the following technical solutions:

The utility model provides a single pile static load testing arrangement, it contains the anchor stake of arranging in the test stake both sides, places the crossbeam in anchor stake top, is located the loading device of crossbeam below, and sets up the anchor connecting device in the crossbeam both sides, and loading device contains hydraulic jack, and hydraulic jack's upper end is connected with the lower surface of crossbeam through last cushion, and hydraulic jack's lower extreme is connected with the upper surface of test stake through lower cushion, its characterized in that: the two sides of the cross beam are provided with supporting components with adjustable heights, and the anchoring connecting device comprises a steel strand cage embedded in the anchor pile, steel strands embedded in the steel strand cage and a reverse pulling locking device for fixing the steel strands on the cross beam.

Further, the anti-pulling locking device comprises a connecting plate fixedly connected with the cross beam, a positioning block placed on the connecting plate and a plurality of clamping blocks placed in the positioning block, a through hole for a steel strand to pass through is formed in the connecting plate, a plurality of inverted cone-shaped inner holes are formed in the positioning block, the outer part of the clamping blocks is an inverted cone-shaped surface, the inner part of the clamping blocks is a cylindrical hole, the clamping blocks are of symmetrical two-half structures, the steel strand sequentially passes through the through hole in the connecting plate, the inverted cone-shaped inner hole in the positioning block and the cylindrical hole in the clamping blocks from bottom to top, and when the steel strand is pulled downwards, the steel strand is fixed on the cross beam through the interaction of the inner cone surface of the inverted cone-shaped inner hole in the positioning block and the outer cone surface of the inverted cone-shaped surface in the clamping blocks, so that the clamping blocks shrink inwards to clamp the steel strand.

Further, the supporting component contains the supporting leg of the hollow structure that can dismantle with the crossbeam and sets up the universal regulation foot in the supporting leg bottom, universal regulation foot from bottom to top set gradually base, articulated head, limiting plate, bracing piece, lock nut and fixation nut, the base is fixed subaerial, the lower extreme of articulated head rotates with the base through the round pin axle and is connected, the up end of articulated head is provided with cylindrical slot on be provided with the limiting plate of dismantling the connection, the lower extreme of bracing piece is provided with the hemisphere head, the bracing piece passes through the hemisphere head rotate and set up in the articulated head cylindrical slot in, be provided with the external screw thread on the bracing piece, lock nut passes through the external screw thread cover establish the bracing piece be close to the one end of hemisphere head, fixation nut places in the top of lock nut, fixation nut passes through the external screw thread cover establish on the bracing piece and with supporting leg fixed connection.

Further, the number of the supporting components is 4, and the supporting components are symmetrically arranged on two sides of the cross beam in an eight-shaped structure.

Further, the height of the outer conical surface of the inverted conical surface in the clamping block is larger than the height of the inner conical surface of the inverted conical inner hole in the positioning block.

Further, the lower middle part of the cross beam extends downwards to form a bulge.

Further, the steel strand is a standard steel strand twisted by seven steel wires, and the nominal tensile strength grade is 1860MPa.

Further, a displacement detection device is further arranged at the center of the test pile and comprises a fixed support fixed on the ground, support pipes penetrating through two sides of the hydraulic jack and detachably connected with the fixed support, a connecting seat fixed in the middle of the support pipes, and a displacement sensor arranged on the connecting seat, wherein a probe of the displacement sensor is in contact with the upper surface of the lower cushion block.

Further, the number of the displacement sensors is 4, and the displacement sensors are uniformly arranged on the same circumference taking the center of the test pile as the center of a circle.

Furthermore, the connecting seat is magnetic, and the supporting tube is made of carbon steel.

Compared with the prior art, the utility model has the beneficial effects that:

1. The supporting components with adjustable heights are arranged on two sides of the cross beam, the length of each supporting component can be independently adjusted by rotating the supporting rods in the supporting components, so that the adjustment of levelness of the cross beam in a ground fixed state is realized, the adjustment is simple and convenient, the uniform stress of the steel strands is ensured, and the safety and stability of static load test are improved;

2. The base at the bottom of the supporting component is movably connected with the ground through the pin shaft, so that the base and the ground can always keep a good contact state under the working condition of a certain gradient, the requirement for adjusting the levelness of the cross beam under various working conditions is met, and the applicable working condition range is wider;

3. The anchoring connection device is characterized in that the steel strands embedded in the steel strand cage and the cross beam are adopted for carrying out reverse pulling fixation, the high tensile strength performance of the steel strands is utilized, the tensile strength of a single anchor pile is greatly improved, the reverse pulling force of the anchoring connection device is greatly improved, the number of the anchor piles can be reduced by at least 1/2 under the conditions that the vertical compressive bearing capacity of a single pile is the same and the diameters of the anchor piles are the same, the additional pile making cost of the anchor piles is reduced, the test time is shortened, the test cost is reduced, the number of the cross beam is reduced, the cross beam structure is simplified, the manufacturing and transportation cost of the cross beam is reduced, the period of the cross beam installation and debugging is shortened, and the working efficiency of the whole test is improved;

4. When the steel strand is reversely pulled downwards, the inner conical surface of the positioning block in the reverse pulling locking device interacts with the outer conical surface of the clamping block, so that the clamping block contracts inwards to hold the steel strand tightly, the steel strand is fixed on the cross beam, the steel strand is fixed by adopting the conical surface wedging connection structure, the steel strand can produce the effect of being pulled more tightly, the reliability of the testing device is further improved, the structure is simple, the dismounting is convenient, and the cost is low.

Drawings

FIG. 1 is a schematic view of an embodiment of the present utility model

FIG. 2 is a front view of FIG. 1

FIG. 3 is a cross-sectional view A-A in FIG. 2

Fig. 4 is a top view of fig. 2

FIG. 5 is an enlarged view of part N of FIG. 1

FIG. 6 is a cross-sectional view of B-B in FIG. 4

FIG. 7 is an enlarged view of part M of FIG. 3

FIG. 8 is a cross-sectional view of C-C of FIG. 7

FIG. 9 is a schematic view of a clamping block according to an embodiment of the present utility model

Fig. 10 is a top view of fig. 9

Reference numerals: test pile 1, anchor pile 2, crossbeam 3, loading device 4, upper cushion 4-1, hydraulic jack 4-2, lower cushion 4-3, supporting component 5, supporting leg 5-1, fixation nut 5-2, lock nut 5-3, bracing piece 5-4, articulated joint 5-5, round pin axle 5-6, base 5-7, limiting plate 5-8, anchor connecting device 6, connecting plate 6-1, steel strand 6-2, locating piece 6-3, clamping piece 6-4, steel strand cage 6-5, displacement detection device 7, fixed bolster 7-1, stay tube 7-2, displacement sensor 7-3, connecting seat 7-4.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

The utility model provides a single pile static load testing device, which is shown in figures 1 to 4, and comprises anchor piles 2 arranged on two sides of a testing pile 1, a cross beam 3 arranged above the anchor piles 2, a loading device 4 positioned below the cross beam 3, and an anchoring connecting device 6 arranged on two sides of the cross beam 3, wherein the loading device 4 comprises a hydraulic jack 4-2, the upper end of the hydraulic jack 4-2 is connected with the lower surface of the cross beam 3 through an upper cushion block 4-1, the lower end of the hydraulic jack 4-2 is connected with the upper surface of the testing pile 1 through a lower cushion block 4-3, supporting components 5 with adjustable heights are arranged on two sides of the cross beam 3, and the anchoring connecting device 6 comprises steel stranded wires 6-2 embedded in the anchor piles 2, steel stranded wire 6-2 embedded in the steel stranded wire cages 6-5 and a reverse pulling locking device for fixing the steel stranded wires 6-2 on the cross beam 3.

In the above embodiment, the supporting components 5 with adjustable heights are arranged on two sides of the cross beam 3, on one hand, after the cross beam 3 is hung above the test pile 1 and the anchor pile 2, the supporting components 5 are fixedly connected to the cross beam 3, the cross beam 3 is supported on the ground by using the supporting components 5, the operation time for adjusting the cross beam 3 in the hanging state is reduced, and potential safety hazards are avoided; on the other hand, the levelness adjustment of the cross beam 3 in the ground fixed state can be realized by independently adjusting the height of each supporting component 5, so that the uniform stress of the steel stranded wires 6-2 is ensured, and the safety and stability of static load test are improved.

In the above embodiment, the steel strands 6-2 pre-buried in the steel strand cages 6-5 are fixed by counter pulling with the cross beam 3, and the high tensile strength of the steel strands 6-2 is utilized to improve the tensile strength of the single anchor pile 2, thereby improving the counter pulling force of the anchor connecting device 6.

In order to efficiently and quickly fix the steel strand 6-2 on the cross beam 3, as shown in fig. 1, 2 and 6, the anti-pulling locking device in the anchoring connection device 6 comprises a connecting plate 6-1 fixedly connected with the cross beam 3, a positioning block 6-3 arranged on the connecting plate 6-1 and a plurality of clamping blocks 6-4 arranged inside the positioning block 6-3, a through hole for the steel strand 6-2 to pass through is arranged on the connecting plate 6-1, a plurality of inverted conical inner holes are arranged on the positioning block 6-3, the outer part of the clamping block 6-4 is an inverted conical surface and the inner part is a cylindrical hole, the clamping blocks 6-4 are of symmetrical two-half structures, the steel strand 6-2 sequentially passes through the through hole in the connecting plate 6-1, the inverted conical inner holes in the positioning block 6-3 and the cylindrical holes in the clamping blocks 6-4 from bottom to top, and when the steel strand 6-2 is pulled down, the inverted conical inner surfaces in the positioning block 6-3 and the conical surfaces in the clamping blocks 6-4 interact to enable the steel strand 6-2 to be clamped tightly and fastened to the cross beam 6-2. The steel strand 6-2 is fixed by adopting the structure with the wedged conical surface, so that the effect that the steel strand 6-2 is pulled more tightly can be generated, the structure is simple, the disassembly and assembly are convenient, the cost is low, and the working efficiency is high.

In order to facilitate adjustment of the levelness of the cross beam 3 and meet the requirement of adjustment of the levelness of the cross beam 3 under various working conditions, as shown in fig. 7 and 8, the supporting component 5 comprises a supporting leg 5-1 which is detachably connected with the cross beam 3 and a universal adjusting foot arranged at the bottom of the supporting leg 5-1, the universal adjusting foot is sequentially provided with a base 5-7, a hinged joint 5-5, a limiting plate 5-8, a supporting rod 5-4, a locking nut 5-3 and a fixing nut 5-2 from bottom to top, the base 5-7 is fixed on the ground, the lower end of the hinged joint 5-5 is rotationally connected with the base 5-7 through a pin shaft 5-6, the upper end face of the hinged joint 5-5 is provided with a cylindrical groove, the lower end of the supporting rod 5-4 is provided with a half ball head, the supporting rod 5-4 is rotationally arranged in the cylindrical groove of the hinged joint 5-5 through the half ball head, the supporting rod 5-4 is provided with an external thread, the locking nut 5-3 is sleeved on the supporting rod 5-4 and is fixedly connected with the supporting rod 5-7 through the external thread nut 5-4, and the locking nut is fixedly sleeved on the supporting rod 5-5 through the external thread 2.

When the embodiment is used, after the lock nut 5-3 and the fixed nut 5-2 are loosened for a certain distance, the support rod 5-4 is screwed into or out of the fixed nut 5-2 by rotating the support rod 5-4, the length distance between the support leg 5-1 and the base 5-7 is changed, the length of the support assembly 5 is adjusted, the function of adjusting the levelness of the cross beam 3 is further realized, and after the levelness adjustment of the cross beam 3 is completed, the lock nut 5-3 is rotated to tightly fasten the fixed nut 5-2, the levelness position of the cross beam 3 is locked, and the stability is improved; the base 5-7 is movably connected with the hinge joint 5-5 through the pin shaft 5-6, so that under the condition that the ground has a certain gradient, the bottom surface of the base 5-7 can be fully contacted with the ground, the requirement of adjusting the levelness of the cross beam 3 under the certain gradient can be met, and the applicable working condition range is wider.

In order to improve the sensitivity of the levelness adjustment of the cross beam 3, as shown in fig. 1, the number of the supporting components 5 is 4, and the supporting components are symmetrically arranged on two sides of the cross beam 3 in an splayed structure.

In order to facilitate the disassembly of the clamping block 6-4 from the positioning block 6-3, as shown in fig. 6, the height of the outer conical surface of the inverted conical surface in the clamping block 6-4 is greater than the height of the inner conical surface of the inverted conical inner hole in the positioning block 6-3, and the height space for the disassembly of the clamping block 6-4 is reserved.

In order to increase the strength and rigidity of the cross beam 3, as shown in fig. 2, the middle part of the cross beam 3 extends downwards to be convex, and the cross beam has a frame structure with a large middle part and small two ends, so that the stability of the whole force transmission system is improved.

In order to further improve the tensile strength of the anchor pile 2, the steel strand 6-2 is a standard steel strand twisted by seven steel wires, and the nominal tensile strength grade is 1860MPa.

In order to provide a detection device matched with the single pile static load testing device, as shown in fig. 1, 4 and 5, a displacement detection device 7 is arranged in the center of a testing pile 1 and comprises a fixed support 7-1 fixed on the ground, support pipes 7-2 penetrating through two sides of a hydraulic jack 4-2 and detachably connected with the fixed support 7-1, a connecting seat 7-4 fixed in the middle of the support pipes 7-2 and a displacement sensor 7-3 arranged on the connecting seat 7-4, and a probe of the displacement sensor 7-3 is contacted with the upper surface of a lower cushion block 4-3. The fixing bracket 7-1 and the supporting tube 7-2 adopt a detachable connection structure, so that the fixing bracket is convenient to install and detach when in test, and meanwhile, the occupied space during transportation can be reduced.

In order to improve accuracy of pile top settlement measurement data, as shown in fig. 1 and 5, the number of the displacement sensors 7-3 in the displacement detection device 7 is 4, and the displacement sensors are uniformly arranged on the same circumference taking the center of the test pile 1 as the center of a circle, and statistical analysis can be performed through 4 groups of data measured by the 4 displacement sensors 7-3.

In order to rapidly mount and dismount the displacement sensor 7-3 in the displacement detection device 7 and rapidly adjust the detection position of the displacement sensor 7-3, the connection seat 7-4 is provided with magnetism, the support tube 7-2 is made of carbon steel, the displacement sensor 7-3 is mounted on the connection seat 7-4, and the connection seat 7-4 is adsorbed on the support tube 7-2 through magnetic force.

It should be noted that: in the prior art, the conventionally used anchor bars in the anchor piles are usually reinforcing bars with the strength grade of HRB400, and the tensile strength Rm of the reinforcing bars with the strength grade of HRB400 is 540MPa according to the standard of GB1499.2-2018 hot rolled ribbed reinforcing bars for reinforced concrete; in the embodiment of the utility model, the steel strand 6-2 pre-buried in the steel strand cage 6-5 is a steel strand for prestressed concrete, typically seven steel wires are twisted into a standard steel strand, and the tensile strength Rm of the steel strand ranges from 1470Mpa to 1960Mpa according to GB/T5224-2014 steel strand for prestressed concrete. It can be seen that the tensile strength of the single steel strand with the same diameter is 2.72-3.62 times of that of the single steel bar, the tensile strength Rm of the single steel strand with the same diameter is 3.44 times of that of the single steel bar according to the comparison that the conventional tensile strength Rm of the single steel strand is 1860MPa, and the tensile strength of the anchor pile adopting the steel strand is 3.44 times of that of the anchor pile 2 adopting the steel bar when the steel strand with the same number and same diameter is buried on the same single anchor pile and compared with the steel bar. In the anchor pile method static load testing device in the prior art, the anchor connecting device adopts a structure that a reinforcing steel bar buried in an anchor pile is welded or bolted with a cross beam to provide counter tension, and because the anchor connecting device is limited by the tensile strength of the reinforcing steel bar, at least more than 4 anchor piles are required to be arranged around the test pile in order to ensure that enough counter tension is provided for the test pile; in the embodiment of the utility model, the anchoring connection device 6 provides counter tension for the test pile 1 by utilizing the structure that the steel strands 6-2 embedded in the steel strand cages 6-5 are fixed with the cross beam 3, compared with the anchor pile method static load test device in the prior art, the equal-diameter and equal-number steel strands are adopted to replace steel bars, and under the condition of the same test condition, the number of anchor piles can be reduced by at least 1/2, thereby reducing the additional pile manufacturing cost, shortening the test time, reducing the test cost, simultaneously reducing the number of cross beams, simplifying the cross beam structure, reducing the manufacturing and transportation cost, shortening the period of installation and debugging and improving the working efficiency of the whole test.

Working principle:

2 anchor piles 2 are symmetrically arranged on two sides of the tested pile 1, and steel stranded wires 6-2 are embedded in steel stranded wire cages 6-5 in the anchor piles 2; hoisting the cross beam 3 above the test pile 1 and the anchor pile 2, respectively connecting support assemblies 5 at two sides of the cross beam 3, and fixing a loading device 4 between the cross beam 3 and the test pile 1; the length of the supporting rods 5-4 in the 4 supporting components 5 is rotated, so that the lower surface of the cross beam 3 is contacted with the upper surface of the upper cushion block 4-1 at the upper end of the hydraulic jack 4-2, and meanwhile, the upper surface of the cross beam 3 is in a horizontal state, and the preliminary adjustment of the height and levelness of the cross beam 3 is completed. Positioning blocks 6-3 are respectively placed on 4 connecting plates 6-1 above the cross beam 3, clamping blocks (6-4) are correspondingly placed in a plurality of inverted cone-shaped inner holes of the positioning blocks 6-3, a hydraulic puller is used for straightening the steel stranded wires 6-2, the steel stranded wires 6-2 sequentially penetrate through the through holes of the connecting plates 6-1, the inverted cone-shaped inner holes of the positioning blocks 6-3 and the inner cylinder holes of the clamping blocks (6-4) from bottom to top, the clamping blocks 6-4 are wedged in the inverted cone-shaped inner holes of the positioning blocks 6-3, a hydraulic jack 4-2 is started to push out a small distance upwards, the cross beam 3 drives the positioning blocks 6-3 and the clamping blocks (6-4) in the positioning blocks 6-3 to rise a small distance together, the steel strand 6-2 is reversely pulled downwards relatively for a small distance, the steel strand 6-2 is fixed on the cross beam 3 by the interaction of the inner conical surface of the positioning block 6-3 and the outer conical surface of the clamping block 6-4 and the inward contraction of the clamping block 6-4 with a two-half structure, at this time, the levelness of the cross beam 3 is finely adjusted by adjusting the length of the supporting rods 5-4 in the 4 supporting components 5 again, and finally, the locking nuts 5-3 on the supporting rods 5-4 are rotated to fasten the fixing nuts 5-2 and lock the levelness of the cross beam 3 by the position of the fastening nuts 5-2, so that the levelness adjustment of the cross beam 3 is completed.

When the static load test is carried out, the ejection force of the hydraulic jack 4-2 is set according to the requirement, the hydraulic jack 4-2 is driven by a hydraulic system to eject upwards, the ejection force of the hydraulic jack 4-2 is transmitted to the cross beam 3 through the upper cushion block 4-1, the middle of the cross beam 3 is subjected to upward thrust, meanwhile, the two ends of the cross beam are subjected to downward tension of the steel strand 6-2, when the ejection force of the hydraulic jack 4-2 reaches a set value, the ejection force is not increased any more, at the moment, the cross beam 3 is subjected to the upward thrust and the downward tension to be equal, so that the ejection force of the hydraulic jack 4-2 is in a static state, the state is kept according to the static load test time requirement, and after the static load dwell time is reached, the sinking amount generated by the test pile 1 is measured by the displacement sensor 7-3 and is displayed on a display. The jacking force of the hydraulic jack 4-2 is set to be loaded step by step, the test pile 1 is loaded step by step, and the sinking amount of the single pile under different load actions is obtained through actual measurement, so that the aim of foundation pile bearing capacity detection is fulfilled.

It should be noted that, in the present utility model, unless explicitly specified and limited otherwise, the terms "connected," "fixed," "disposed," and the like are to be construed broadly, and for example, "fixed" may be either a fixed connection or a removable connection or be integrated; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present utility model can be understood by those skilled in the art according to the specific circumstances.

In addition, the technical solutions of the embodiments of the present utility model may be combined with each other, but it is necessary to base the implementation on the basis of those skilled in the art, and when the technical solutions are contradictory or cannot be implemented, it should be considered that the combination of the technical solutions does not exist, and is not within the scope of protection claimed by the present utility model.

Claims (10)

1. The utility model provides a single pile static load testing arrangement, contain anchor stake (2) of arranging in test stake (1) both sides, place crossbeam (3) in anchor stake (2) top, be located loading device (4) of crossbeam (3) below, and set up anchor connecting device (6) in crossbeam (3) both sides, loading device (4) contain hydraulic jack (4-2), the upper end of hydraulic jack (4-2) is connected with the lower surface of crossbeam (3) through last cushion (4-1), the lower extreme of hydraulic jack (4-2) is connected with the upper surface of test stake (1) through lower cushion (4-3), its characterized in that: the two sides of the cross beam (3) are provided with supporting components (5) with adjustable heights, and the anchoring connecting device (6) comprises a steel strand cage (6-5) buried in the anchor pile (2), steel strands (6-2) embedded in the steel strand cage (6-5) and a reverse pulling locking device for fixing the steel strands (6-2) on the cross beam (3).

2. A single pile static load testing device according to claim 1, wherein: the anti-pulling locking device comprises a connecting plate (6-1) fixedly connected with a cross beam (3), a positioning block (6-3) placed on the connecting plate (6-1) and a plurality of clamping blocks (6-4) placed inside the positioning block (6-3), wherein a through hole through which a steel strand (6-2) passes is formed in the connecting plate (6-1), a plurality of inverted conical inner holes are formed in the positioning block (6-3), the outer part of the clamping block (6-4) is of an inverted conical surface, the inner part of the clamping block is of a cylindrical hole, the clamping blocks (6-4) are of symmetrical two-half structures, the steel strand (6-2) sequentially passes through the through hole in the connecting plate (6-1), the inverted conical inner hole in the positioning block (6-3) and the cylindrical hole in the clamping block (6-4) from bottom to top, and when the steel strand (6-2) is pulled downwards, the inner conical surface of the inverted conical inner hole in the positioning block (6-3) and the inverted conical surface in the clamping block (6-4) interact to enable the steel strand (6-2) to be fastened to the cross beam (6-2).

3. A single pile static load testing device according to claim 1, wherein: the support component (5) comprises a support leg (5-1) with a hollow structure and a universal adjusting foot, wherein the support leg (5-1) is detachably connected with the cross beam (3), the universal adjusting foot is arranged at the bottom of the support leg (5-1), a base (5-7), a hinge joint (5-5), a limiting plate (5-8), a support rod (5-4), a locking nut (5-3) and a fixing nut (5-2) are sequentially arranged from bottom to top, the base (5-7) is fixed on the ground, the lower end of the hinge joint (5-5) is rotationally connected with the base (5-7) through a pin shaft (5-6), a cylindrical groove is formed in the upper end face of the hinge joint (5-5), a limiting plate (5-8) which is detachably connected is arranged on the cylindrical groove, a semispherical head is arranged at the lower end of the support rod (5-4), the support rod (5-4) is rotationally arranged in the cylindrical groove of the hinge joint (5-5) through the semispherical head, an external thread is arranged on the support rod (5-4), the locking nut (5-3) is sleeved on one end of the support rod (5-3) close to the locking nut (5-2), the fixing nut (5-2) is sleeved on the supporting rod (5-4) through the external thread and is fixedly connected with the supporting leg (5-1).

4. A single pile static load testing device according to claim 1, wherein: the number of the supporting components (5) is 4, and the supporting components are symmetrically arranged on two sides of the cross beam (3) in an splayed structure.

5. A single pile static load testing device according to claim 2, wherein: the height of the outer conical surface of the reverse conical surface in the clamping block (6-4) is larger than that of the inner conical surface of the reverse conical inner hole in the positioning block (6-3).

6. A single pile static load testing device according to any one of claims 1-5, wherein: the middle part of the lower part of the cross beam (3) extends downwards to form a bulge.

7. A single pile static load testing device according to any one of claims 1-5, wherein: the steel strand (6-2) is a standard steel strand twisted by seven steel wires, and the nominal tensile strength grade is 1860MPa.

8. A single pile static load testing device according to any one of claims 1-5, wherein: the center of the test pile (1) is also provided with a displacement detection device (7), which comprises a fixed support (7-1) fixed on the ground, support pipes (7-2) penetrating through two sides of the hydraulic jack (4-2) and detachably connected with the fixed support (7-1), a connecting seat (7-4) fixed in the middle of the support pipes (7-2), and a displacement sensor (7-3) arranged on the connecting seat (7-4), wherein a probe of the displacement sensor (7-3) is contacted with the upper surface of the lower cushion block (4-3).

9. The single pile static load testing device according to claim 8, wherein: the number of the displacement sensors (7-3) is 4, and the displacement sensors are uniformly arranged on the same circumference taking the center of the test pile (1) as the center of a circle.

10. The single pile static load testing device according to claim 8, wherein: the connecting seat (7-4) is magnetic, and the supporting tube (7-2) is made of carbon steel.