KR102612761B1 - Apparatus for dynamic pile load test - Google Patents

Abstract

The present invention includes a main frame mounted on the pile head; a drop hammer disposed on the upper side of the pile and provided to be capable of being raised and lowered on the main frame; a lifting unit disposed on the upper side of the main frame and configured to raise and lower the drop hammer; and an alignment unit that aligns the central axis of the lifting unit with the central axis of the pile when the main frame is mounted on the pile head.
In addition, the dynamic load test device of the present invention serves to drop a plurality of rams of a drop hammer onto a pile, and may include a catch and a locking unit that can minimize the occurrence of whiplash when a plurality of rams hit a pile. .

Description

Dynamic load test device {APPARATUS FOR DYNAMIC PILE LOAD TEST}

The present invention relates to a dynamic load test device.

Recently, in accordance with the trend toward larger structures and the development of soft ground, the pile construction method of driving piles into the ground as the foundation of a structure is increasing. As the pile driven into the ground as the foundation of the structure receives the entire load of the structure, the allowable bearing capacity of the pile is calculated for the safety of the structure.

There are many ways to calculate the allowable bearing capacity of a pile, but the pile load test is generally used as the most reliable method. These pile load test methods include static load test and dynamic load test.

In the static load test, a loading device is installed on the head of the pile, a load two to three times the design load is loaded on the loading device, the load and settlement are measured, and the yield load or ultimate load of the pile is calculated. Through this, the allowable load of the pile is calculated. As a method of calculating bearing capacity, a dead load equivalent to 2 to 3 times the design reaction force must be loaded on the pile head of a small area, which has the disadvantage of making it difficult to ensure worker safety and requiring a lot of testing cost and testing time.

On the other hand, the dynamic load test measures the stress and velocity waves generated in the pile by striking the pile head with a ram weighing 1 to 2% of the allowable bearing capacity, and calculates the allowable bearing capacity of the pile, which requires less test cost and testing time. It has the advantage of being able to obtain a variety of analysis data.

Therefore, recently, dynamic load tests have been widely used when calculating the allowable bearing capacity of piles. Looking at the procedure of the dynamic load test method, when hitting the pile head, the pile head is smoothed so that the impact is evenly applied to the pile head, a measuring gauge is attached to the pile, and the measuring gauge is connected to the driving analyzer. Afterwards, the test is completed by analyzing the measurement data obtained by mounting the hammer on the striking machine and striking the head of the pile using the hammer.

Types of hammers used during the dynamic loading test process include diesel hammers, hydraulic hammers, and steam hammers. In general, a simple drop hammer is mainly used. The drop hammer is lifted to the top of the pile head using a crane, etc., and then dropped from a certain height. The principle is to strike a pile by dropping it. Recently, the size of drop hammers and piles is increasing in accordance with the trend of larger structures, so there is a lot of development for accurate and efficient hitting methods.

The conventional dynamic load test device is connected by a ring by heavy equipment such as a crane so that the drop hammer is located at the upper part of a predetermined height from the pile that is poured into the ground and the head is prepared. A guide pipe that guides the drop hammer surrounds the outer circumferential surface of the drop hammer and is provided at the top of the pile.

In addition, four pairs of measurement gauges are attached to the outer peripheral surface of the pile at a predetermined height from the ground surface, and the measurement gauges are generally a pair of strain gauges and acceleration gauges.

The drop hammer is manufactured as a single piece in a cylindrical shape and has various sizes and weights depending on the needs of the dynamic load test. Therefore, the striking work is performed by selecting the size of the drop hammer according to the size of the pile and the degree of load. The drop hammer is connected to a ring using heavy equipment such as a crane, placed at a predetermined height, and operated by heavy equipment to lower the drop hammer. The striking work is carried out by striking the central part of the pile head by allowing it to fall freely. At this time, the drop hammer passes through the inside of the guide pipe mounted on the pile head and falls on the center of the pile head, striking the pile.

In this way, the shock wave transmitted to the pile is measured as a speed wave and a stress wave through a measuring gauge attached to the pile, and the allowable bearing capacity of the pile and the ground is analyzed and calculated through a strike analyzer. Briefly looking at the impact analysis method using a strike analyzer, the analysis method based on the dynamic bearing capacity formula has been traditionally used, and recently, wave analysis has been used to obtain more accurate data by modeling the pile and the ground conditions of the pile's main surface in detail. Strike analysis methods based on equations and case methods are used. Therefore, before the dynamic load test, initial data such as gauge attachment position and pile penetration depth are input into the impact analyzer, and then impact analysis work is performed accordingly.

The results of the impact analysis vary depending on the speed of compression deformation due to the transfer of the impact stress generated from the pile head and the speed of reflection from the pile tip, that is, the speed of the shock wave. The speed of the shock wave is affected by the frictional force and tip bearing capacity of the ground against the pile, and the ground into which the pile penetrates generally has various ground characteristics depending on the depth.

In a conventional dynamic load test device, when the pile head is inclined, eccentricity may occur between the inclined head of the pile and the guide pipe as the guide pipe is mounted on the inclined head of the pile. At this time, when the drop hammer falling along the guide pipe hits the pile head, there was a problem in that the drop hammer struck a point eccentric from the slanted head of the pile due to the eccentricity between the slanted head of the pile and the guide pipe.

Domestic Registered Patent Publication No. 10-1905446 (2018.10.01.)

The present invention was created to solve the above-mentioned problems. The purpose of the present invention is to align the central axis of the pile and the central axis of the lifting unit when the main frame is mounted on the pile head, thereby aligning the pile head and the main frame. The purpose is to provide a dynamic load test device that can minimize the eccentricity between the central axes of the drop hammers falling along the main frame and enable the drop hammers falling along the main frame to accurately hit the center of the pile head.

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned can be clearly understood by those skilled in the art from the description below.

A dynamic load testing device according to an embodiment of the present invention includes a main frame mounted on the pile head; a drop hammer disposed on the upper side of the pile and provided to be capable of being raised and lowered on the main frame; a lifting unit disposed on the upper side of the main frame and configured to raise and lower the drop hammer; And when the main frame is mounted on the pile head, it includes an alignment unit that aligns the central axis of the lifting unit and the central axis of the pile.

In addition, the alignment unit includes an upper link coupled to the lower end of the lifting unit; a lower link coupled to the upper end of the main frame; And it may include a rotation axis that couples the lower link to enable relative rotation with respect to the upper link.

Additionally, the alignment unit includes a first upper bracket coupled to one side of the upper link; a second upper bracket coupled to the other side of the upper link; a first lower bracket disposed to be spaced apart from the lower side of the first upper bracket and coupled to one side of the lower link; a second lower bracket disposed to be spaced apart from the lower side of the second upper bracket and coupled to the other side of the lower link; a first bolt with one side coupled to the first upper bracket and the other side elastically supported by the first lower bracket; And it may include a second bolt on one side of which is coupled to the second upper bracket and the other side of which is elastically supported by the second lower bracket.

Additionally, the upper link and the lower link may be configured as a pair.

In addition, the drop hammer includes a plurality of RAMs stacked along the vertical direction of the main frame; and an assembly rod for fastening the plurality of rams, and a rounded portion may be formed at a corner of the ram disposed at the lowermost side among the plurality of rams.

Additionally, the ram includes alignment holes penetrating along the vertical direction of the ram; and an alignment protrusion extending from the alignment hole, wherein two adjacent RAMs among the plurality of RAMs can be engaged and aligned through the alignment protrusion and the alignment hole.

Additionally, a shackle hole may be formed in the alignment protrusion along a vertical direction perpendicular to the vertical direction of the ram.

Additionally, a bottom plate of a shape corresponding to the pile head may be provided on the lower surface of the main frame.

Additionally, it may include a locking unit that locks or unlocks the lifting unit and the drop hammer.

Additionally, the locking unit may include a hook groove provided in the lifting unit, and a hook provided in the drop hammer and locked or unlocked in the hook groove.

Other specific details of the invention are included in the detailed description and drawings.

The dynamic load test device according to an embodiment of the present invention aligns the central axis of the pile and the central axis of the elevating unit when the main frame is mounted on the pile head, thereby ensuring the eccentricity between the drop hammer falling along the pile head and the main frame. can be minimized, and the drop hammer falling along the main frame has the effect of accurately hitting the center of the pile head.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

Figure 1 is a front view showing a dynamic load test device according to an embodiment of the present invention.
Figure 2 is an enlarged view showing the alignment part of the dynamic load test device according to an embodiment of the present invention.
Figure 3 is an enlarged view showing the operation process of the alignment part of the dynamic load test device according to an embodiment of the present invention.
Figure 4 is an exploded cross-sectional view showing the drop hammer of the dynamic load test device according to an embodiment of the present invention.
Figure 5 is a plan view showing a RAM disposed on the uppermost side among a plurality of RAMs in a dynamic load test device according to an embodiment of the present invention.
Figure 6 is a plan view showing a ram located between the uppermost and lowermost sides among a plurality of rams of a dynamic load test device according to an embodiment of the present invention.
Figure 7 is a plan view showing a ram disposed on the lowest side among a plurality of rams of a dynamic load test device according to an embodiment of the present invention.
Figure 8 is a bottom view showing the lower surface of the main frame of the dynamic load test device according to an embodiment of the present invention.
Figure 9 is an enlarged view showing the locking unit of the dynamic load test device according to an embodiment of the present invention.
Figure 10 is a side view showing the locking unit of the dynamic load test device according to an embodiment of the present invention.

The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. The present embodiments are merely provided to ensure that the disclosure of the present invention is complete and to provide a general understanding of the technical field to which the present invention pertains. It is provided to fully inform the skilled person of the scope of the present invention, and the present invention is only defined by the scope of the claims.

The terminology used herein is for describing embodiments and is not intended to limit the invention. As used herein, singular forms also include plural forms, unless specifically stated otherwise in the context. As used in the specification, “comprises” and/or “comprising” does not exclude the presence or addition of one or more other elements in addition to the mentioned elements. Like reference numerals refer to like elements throughout the specification, and “and/or” includes each and every combination of one or more of the referenced elements. Although “first”, “second”, etc. are used to describe various components, these components are of course not limited by these terms. These terms are merely used to distinguish one component from another. Therefore, it goes without saying that the first component mentioned below may also be a second component within the technical spirit of the present invention.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with meanings commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless clearly specifically defined.

Spatially relative terms such as “below”, “beneath”, “lower”, “above”, “upper”, etc. are used as a single term as shown in the drawing. It can be used to easily describe the correlation between a component and other components. Spatially relative terms should be understood as terms that include different directions of components during use or operation in addition to the directions shown in the drawings. For example, if a component shown in a drawing is flipped over, a component described as “below” or “beneath” another component will be placed “above” the other component. You can. Accordingly, the illustrative term “down” may include both downward and upward directions. Components can also be oriented in other directions, so spatially relative terms can be interpreted according to orientation.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

Figure 1 is a front view showing a dynamic load test device according to an embodiment of the present invention, Figure 2 is an enlarged view showing an alignment portion of a dynamic load test device according to an embodiment of the present invention, and Figure 3 is an embodiment of the present invention. It is an enlarged view showing the operation process of the alignment part of the dynamic load test device according to , Figure 4 is an exploded cross-sectional view showing the drop hammer of the dynamic load test device according to an embodiment of the present invention, and Figure 5 is an exploded view according to an embodiment of the present invention. It is a plan view showing the ram located at the uppermost side among the plurality of rams of the dynamic load test device, and Figure 6 shows the ram located between the uppermost and lowermost side among the plurality of rams of the dynamic load test device according to an embodiment of the present invention. It is a plan view, and Figure 7 is a plan view showing the ram disposed on the lowest side among the plurality of rams of the dynamic load test device according to an embodiment of the present invention, and Figure 8 is the main frame of the dynamic load test device according to an embodiment of the present invention. This is a bottom view showing the underside of .

As shown in Figures 1 and 2, the dynamic load test apparatus according to an embodiment of the present invention includes a main frame 100, a drop hammer 200, an elevating unit 300, and an alignment unit 500.

The main frame 100 may serve as the basic body of the present invention and may serve to guide the lifting and lowering of the drop hammer 200. This main frame 100 can be mounted on the head of the pile 10. In addition, the main frame 100 connects a plurality of vertical beams 110 arranged along the circumference of the head of the pile 10 and mounted around the head of the pile 10, and two vertical beams 110 adjacent to each other. It may include a plurality of horizontal beams 120.

As an example, a guide beam 111 for guiding the lifting and lowering of the drop hammer 200 is formed around the inner circumference of the main frame 100 along the vertical direction of the main frame 100, and the ram ( A guide groove 214 that is raised and lowered along the guide beam 111 may be formed along the vertical direction of the drop hammer 200 on the outer circumference of the 210). Here, the guide beam 111 and the guide groove 214 may be composed of a plurality, the plurality of guide beams 111 may be arranged along the inner circumference of the main frame 100, and the plurality of guide grooves 214 ) may be provided at the center of each side of the RAM 210. Additionally, the guide beam 111 and the guide groove 214 may have shapes that correspond to each other.

As an example, referring to FIG. 8, a bottom plate 102 having a shape corresponding to the head of the pile 10 may be provided on the lower surface of the main frame 100.

The drop hammer 200 may serve to hit the head of the pile 10. This drop hammer 200 is disposed on the upper side of the pile 10 and can be provided to be lifted up and down on the main frame 100. In addition, the drop hammer 200 can freely fall along the main frame 100 while being placed at a specific drop position on the upper side of the pile 10, hitting the head of the pile 10.

The drop hammer 200 may include a plurality of rams 210 and an assembly rod 220.

A plurality of RAMs 210 may be stacked along the vertical direction of the main frame 100. Here, each ram 210 may be formed with an alignment hole 211 penetrating along the vertical direction of the ram 210 and an alignment protrusion 212 extending upward from the alignment hole 211. Therefore, when a plurality of RAMs 210 are stacked along the vertical direction of the main frame 100, two RAMs 210 that are adjacent to each other among the plurality of RAMs 210 have the alignment protrusion 212 and the alignment hole 211. ), the plurality of RAMs 210 stacked along the vertical direction of the main frame 100 may be aligned in the vertical direction of the main frame 100. Additionally, a shackle hole 213 may be formed in the alignment protrusion 212 along a vertical direction perpendicular to the vertical direction of the ram 210. A crane shackle may be coupled to this shackle hole 213.

For example, referring to FIGS. 4 and 5 , the hook 430 of the locking unit 400, which will be described later, may be coupled to the RAM 210 disposed on the uppermost side among the plurality of RAMs 210. Additionally, the RAM 210 disposed on the uppermost side among the plurality of RAMs 210 may have a plate shape.

For example, referring to FIGS. 4 and 6 , one or more RAMs 210 disposed between the uppermost and lowermost sides of the plurality of RAMs 210 may have a plate shape.

For example, referring to FIGS. 4 and 7 , a rounded portion 215 may be formed at a corner of the RAM 210 disposed at the lowest side among the plurality of RAMs 210 . These round portions 215 may be formed at each corner of the plurality of RAMs 210 . Accordingly, the RAM 210 disposed at the lowest side among the plurality of RAMs 210 may have an overall shape close to a circular shape. Through this, when the ram 210 disposed on the lowest side of the rams 210 strikes the head of the pile 10, the striking stress can be applied uniformly throughout the head of the pile 10.

For example, the total weight of the plurality of rams 210 is preferably greater than that of the pile 10 or is 10 times or more the weight per 1 m of the diameter of the pile 10. In addition, in the case of cast-in-place piles, it is preferable that the total weight of the plurality of rams 210 is 1 to 2% of the allowable bearing capacity of the pile 10. In addition, when striking the head of the pile 10, it is preferable that the distance between the plurality of rams 210 and the pile head, that is, the falling height, is 2 m or less.

The assembly rod 220 may serve to fasten a plurality of RAMs 210 stacked along the vertical direction of the main frame 100. Here, the assembly rod 220 may penetrate a plurality of rams 210 stacked along the vertical direction of the main frame 100, and each ram 210 has a through hole through which the assembly rod 220 passes. can be formed. Additionally, threads may be formed on the outer peripheral surface of the assembly rod 220, and a pair of assembly nuts 230 may be screwed to both ends of the assembly rod 220, respectively. At this time, a pair of assembly nuts 230, respectively screwed to both ends of the assembly rod 220, move in a direction closer to each other and tighten the plurality of rams 210, thereby tightening the plurality of rams 210. It can be.

The lifting unit 300 is disposed on the upper side of the main frame 100 and may serve to raise and lower the drop hammer 200. Referring to FIG. 1, the lifting unit 300 may be placed above the drop hammer 200. As an example, the lifting unit 300 may be an actuator, and the rod 310 of the actuator may be coupled to the locking unit 400. Additionally, the rod 310 of the actuator may be lifted and lowered by a hydraulic device.

Additionally, the lifting unit 300 may be hingedly coupled to the main frame 100. Therefore, when the main frame 100 is mounted on the head of the pile 10, the main frame is aligned with the central axis of the pile 10 or the vertical direction by the weight of the drop hammer 200. The lifting unit 300 may be rotated relative to 100 .

As an example, the lifting unit 300 may lift the drop hammer 200 and the locking unit 400 while being locked with the drop hammer 200 through the locking unit 400. Additionally, the lifting unit 300 can lift and lower only the locking unit 400 in a state in which the drop hammer 200 and the lock are released through the locking unit 400.

The alignment unit 500 aligns the central axis of the lifting unit 300 with the central axis of the pile 10 by the rotation axis 530, which will be described later, when the main frame 100 is mounted on the head of the pile 10. can play a role.

The alignment unit 500 can facilitate transportation of the device by detachably combining the lifting unit 300 and the main frame 100, and when the main frame 100 is mounted on the head of the pile 10 , it is possible to facilitate the combination of the lifting unit 300 and the main frame 100.

In addition, when the main frame 100 is mounted at an angle on the head of the pile 10, the alignment unit 500 is connected to the main frame 100 by the first and second computer bolts 580 and 590, which will be described later. The position and angle of can be adjusted so that the main frame 100 can be aligned with the pile 10.

The alignment unit 500 includes an upper link 510, a lower link 520, a rotation axis 530, a first upper bracket 540, a second upper bracket 550, a first lower bracket 560, and a second lower bracket. It may include a bracket 570, a first computer bolt 580, and a second computer bolt 590.

The upper link 510 may be coupled to the lower end of the lifting unit 300. As an example, the upper link 510 may be integrally connected to the lower end of the lifting unit 300.

The lower link 520 may be coupled to the upper part of the main frame 100. As an example, the lower link 520 may be integrally connected to the upper part of the main frame 100.

The rotation shaft 530 may couple the lower link 520 to relative rotation with respect to the upper link 510.

The upper link 510, lower link 520, and rotation shaft 530 serve to couple the main frame 100 to the lifting unit 300 so as to be relatively rotatable. Therefore, when the main frame 100 is mounted on the head of the pile 10 through the upper link 510, the lower link 520, and the rotation axis 530, the central axis of the lifting unit 300 and the pile 10 The lifting unit 300 may be rotated relative to the main frame 100 so that its central axis is aligned. As a result, when the main frame 100 is mounted on the head of the pile 10, if the central axis of the pile 10 and the central axis of the main frame 100 do not match, the central axis of the pile 10 and the main frame The eccentricity (ΔL1 in FIG. 3) between the central axes of the drop hammer 200 falling along 100 can be minimized (ΔL2 in FIG. 3), and then the drop hammer falling along the main frame 100 (200) can accurately hit the center of the head of the pile (10). (However, the amount of eccentricity can be reduced by the L2/L1 ratio. See Figure 3)

For example, the upper link 510 and the lower link 520 may be configured as a pair. Here, the pair of upper links 510 may be respectively coupled to both sides of the lower end of the lifting unit 300. Additionally, the pair of lower links 520 may be coupled to both sides of the upper end of the main frame 100, respectively. You can.

The first upper bracket 540 may be coupled to one side of the upper link 510.

The second upper bracket 550 may be coupled to the other side of the upper link 510.

For example, the first upper bracket 540 and the second upper bracket 550 may have a wing shape to maintain the equilibrium state of the upper link 510. At this time, the wing shape is such that the vertical width of one area adjacent to the upper link 510 in the first upper bracket 540 and the second upper bracket 550 is the same as that of the first upper bracket 540 and the second upper bracket 550. ), a haunch larger than the vertical width of other areas non-adjacent to the upper link 510 may be placed.

The first lower bracket 560 may be spaced apart from the lower side of the first upper bracket 540 and may be coupled to one side of the lower link 520.

The second lower bracket 570 may be spaced apart from the lower side of the second upper bracket 550 and may be coupled to the other side of the lower link 520.

One side of the first bolt 580 may be coupled to the first upper bracket 540 and the other side may be elastically supported by the first lower bracket 560.

One side of the second bolt 590 may be coupled to the second upper bracket 550 and the other side may be elastically supported by the second lower bracket 570.

These first computerized bolts 580 and second computerized bolts 590 may serve to allow or control the shaking of the main frame 100. Specifically, the length that the first computer bolt 580 protrudes from the first upper bracket 540 to the first lower bracket 560 and the second computer bolt 590 protrude from the second upper bracket 550 to the second lower bracket By adjusting the protruding length of the bracket 570, the fluctuation of the main frame 100 can be allowed or adjusted.

Hereinafter, the main frame 100 of the dynamic load test device according to an embodiment of the present invention is to be mounted on the head of the pile 10, and the alignment portion 500 is located between the central axis of the main frame 100 and the pile 10. The process of aligning the central axis will be explained in detail. The following process can be performed by the user or a control unit that controls heavy equipment such as a crane.

First, after the main frame 100 is raised to the upper side of the pile 10, the main frame 100 is lowered, and the main frame 100 is mounted on the head of the pile 10. Here, the raising and lowering of the main frame 100 may be carried out by heavy equipment such as a crane.

Next, the plurality of RAMs 210 of the drop hammer 200 are aligned on the bottom plate 102 of the main frame 100. Here, the plurality of RAMs 210 may be fastened with an assembly rod 200 and a rough nut 230.

Next, with the lifting unit 300 and the locking unit 400 coupled to the main body of the main frame 100, the main body of the main frame 100 and the lifting unit 300 are connected to the base plate 102 using a crane. It is mounted on a plurality of RAMs (210).

Next, as the lifting unit 300 is coupled to the main frame 100 for relative rotation through the upper link 510, lower link 520, and rotation shaft 530, it falls along the main frame 100. The lifting unit 300 may be rotated relative to the main frame 100 so that the central axis of the plurality of rams 210 of the drop hammer 200 and the central axis of the pile 10 are aligned. As a result, when the main frame 100 is mounted on the head of the pile 10, the central axis of the pile 10 and the central axis of the lifting unit 300 are automatically aligned, so that the central axis of the pile 10 and the main frame 100 are aligned. The eccentricity between the plurality of rams 210 of the drop hammer 2000 falling along the frame 100 can be minimized, and then, the plurality of rams 210 of the drop hammer 200 falling along the main frame 100 This can accurately hit the center of the head of the pile (10) (see Figure 3).

Subsequently, if necessary, the dynamic load test can be completed by analyzing the measurement data obtained from the measurement gauge attached to the pile 10 with a strike analyzer. For example, the measurement gauge is a strain gauge and an acceleration gauge in pairs. It can be used, and typically, two pairs or four pairs can be used.

Figure 9 is an enlarged view showing the locking unit of the dynamic load testing device according to an embodiment of the present invention, and Figure 10 is a side view showing the locking unit of the dynamic load testing device according to an embodiment of the present invention.

As shown in FIGS. 9 and 10, the dynamic load test device according to an embodiment of the present invention may further include a locking unit 400.

The locking unit 400 may function to lock or unlock the lifting unit 300 and the drop hammer 200.

If the locking unit 400 is comprehensively defined, the locking unit 400 is provided in the hook groove 421 provided in the lifting unit 300 and the drop hammer 200, and locks or unlocks the hook groove 421. It may include a hook 430. Here, the hook groove 421 may be provided in a pair of catches 420, which will be described later.

If the locking unit 400 is specifically defined, the locking unit 400 includes a base 410, a pair of catches 420, a hook 430, a friction support portion 440, a locking drive portion 450, and a catch house ( 460). Here, the base 410, a pair of catches 420, the friction support part 440, the locking drive part 450, and the catch house 460 may be provided in the lifting unit 300, and the hook 430 may be provided in the drop. It may be provided in the hammer 200.

The base 410 is coupled to the lifting unit 300 and can be lifted and lowered by the lifting unit 300. As an example, the base 410 may have a plate shape.

As an example, a pair of cam grooves 411 may be formed in the base 410 to guide the rotation of a pair of catches 420, which will be described later, and the pair of catches 420 may be formed along a pair of cam holes. A pair of rotating cams may each be formed.

A pair of catches 420 are rotatably coupled to both sides of the base 410, and a hook groove 421 may be formed on the inner surface. Here, the hook groove 421 may be locked with the hook 430 inserted between the pair of catches 420. Additionally, the hook groove 421 may be unlocked from the hook 430 inserted and released from between the pair of catches 420. For reference, insertion release is defined as discharge from a specific falling height.

The catch 420 may include a first inclined portion 422, a second inclined portion 423, a hook groove inclined portion 424, and a seating portion 425.

The first inclined portion 422 is formed on the lower side of the hook groove 421 in the catch 420, and may have a shape in which the width protruding from the central axis of the catch 420 increases toward the upper side of the catch 420. Here, the hook 430 can be inserted or uninserted between the first inclined portions 422 of the pair of catches 420. At this time, when the hook 430 is inserted between the first inclined portions 422 of the pair of catches 420, the hook 430 moves the second inclined portions 423 of the pair of catches 420 away from each other. As pushing in the direction, the first inclined portions 422 of the pair of catches 420 may rotate in a direction to approach each other. Thereafter, when the hook 430 is inserted and released from between the first inclined portion 422 of the pair of catches 420, due to the load of the hook 430 and the ram 210, the pair of catches 420 The lower parts can be rotated in a direction away from each other.

The second inclined portion 423 may be formed on the upper side of the hook groove 421, and may have a width protruding from the central axis of the catch 420 that decreases toward the upper side of the catch 420. Here, the friction support portion 440 may be friction supported or released from the friction support between the second inclined portions 423 of the pair of catches 420 while the hook 430 is locked in the hook groove 421. At this time, when the friction support portion 440 is inserted between the second inclined portions 423 of the pair of catches 420 with the hook 430 locked in the hook groove 421, the friction support portion 440 is one side. As the upper parts of the pair of catches 420 are pushed in a direction away from each other, the upper part of the pair of catches 420 is rotated in a direction away from each other and the lower part of the pair of catches 420 is rotated in a direction closer to each other. Afterwards, as the lower part of the pair of catches 420 comes into close contact with the hook 430, the rotation of the pair of catches 420 is restricted, and between the second inclined portion 423 of the pair of catches 420 The friction support portion 440 may be friction supported. Thereafter, when the friction support portion 440 is inserted and released from between the second inclined portions 423 of the pair of catches 420, the friction support portion ( The friction support of 440 may be released, and the rotation restriction of the pair of catches 420 may also be released.

The hook groove inclined portion 424 is formed in the lower part of the hook groove 421, and may have a shape in which the width protruding from the central axis of the catch 420 decreases toward the upper side of the catch 420. This hook groove The inclined portion 424 may serve to guide the hook 430 inserted between the first inclined portions 422 of the pair of catches 420 to be inserted into the hook groove 421. Additionally, the hook groove inclined The portion 424 may also serve to guide the hook 430 that is inserted and released from the hook groove 421 between the first inclined portions 422 of the pair of catches 420.

The seating portion 425 is formed in a stepped shape on the lower side of the second inclined portion 423, so that the corner of the friction inclined portion 441 of the friction support portion 440, which will be described later, can be seated. This seating portion 425 may serve to limit the depth at which the friction support portion 440 is inserted between the second inclined portions 423 of the pair of catches 420.

The hook 430 is provided on the drop hammer 200, and is inserted between a pair of catches 420 and locked with the hook groove 421, or is inserted and released between the pair of catches 420 to lock into the hook groove 421. ) and can be unlocked. As previously described, the hook 430 may be inserted or de-inserted between the first inclined portions 422 of the pair of catches 420. Additionally, the hook 430 may have an arrowhead shape.

The friction support portion 440 is coupled to the base 410 to be able to lift and is inserted between a pair of catches 420 with the hook 430 locked in the hook groove 421, and is friction supported or a pair of catches 420. It can be inserted and released from between the catches 420 and the friction support can be released. As previously described, the friction support portion 440 is inserted between the second inclined portions 423 of the pair of catches 420 and is friction supported or positioned between the second inclined portions 423 between the pair of catches 420. It can be released from insertion and the friction support can be released.

The friction support portion 440 may include a pair of friction inclined portions 441. The pair of friction inclined portions 441 are formed on both sides of the friction support portion 440 and the inclination of the second inclined portion 423 It may have a tilt angle corresponding to the angle. In other words, a pair of friction inclined portions 441 are formed on both sides of the friction support portion 440, and each friction inclined portion 441 moves toward the upper side of the friction support portion 440, along the central axis of the friction support portion 440. It may have a shape in which the width protruding from it increases, and may have an inclination angle corresponding to the inclination angle of the second inclined portion 423. As an example, a pair of friction inclined portions 441 may be formed on both sides of the friction support portion 440 in the left and right directions.

The locking drive unit 450 is provided in the lifting unit 300 and may serve to lift the friction support unit 440. As an example, the locking drive unit 450 may be an actuator provided in the lifting unit 300, and the rod 451 of the actuator may be coupled to the friction support unit 440.

The catch house 460 is provided on the base 410, accommodates the upper part of the pair of catches 420, and may serve to limit the rotation angle of the pair of catches 420. As an example, the catch house 460 may limit the rotation angle at which the upper portions of the pair of catches 420 are rotated in a direction away from each other. In addition, the catch house 460 may restrict rotation of the upper portions of the pair of catches 420 in a direction away from each other when the friction support portion 440 is frictionally supported between the upper portions of the pair of catches 420. .

For example, an auxiliary guide groove 461 may be formed in the catch house 460 to guide the lifting and lowering of the friction support part 440, and the friction support part 440 may be raised and lowered along the auxiliary guide groove 461. . Alternatively, the auxiliary guide groove 461 may be formed along the vertical direction of the catch house 460.

As an example, the dynamic load test device according to an embodiment of the present invention may be provided with a main ring to which a shackle can be fastened around the upper end of the main frame 100 for easy transportation of the main frame 100.

According to the present invention, the dynamic load test device according to an embodiment of the present invention aligns the central axis of the pile and the central axis of the main frame when the main frame is mounted on the pile head, thereby reducing the eccentricity between the pile head and the main frame. This can be minimized and has the effect of allowing the drop hammer falling along the main frame to accurately hit the center of the pile head.

Above, embodiments of the present invention have been described with reference to the attached drawings, but those skilled in the art will understand that the present invention can be implemented in other specific forms without changing its technical idea or essential features. You will be able to understand it. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive.

10: stake
100: main frame
111: Guide beam
102: bottom plate
110: Vertical section steel
120: horizontal beam
200: Drophammer
210: RAM
211: Alignment hole
212: Alignment protrusion
213: Shackle hole
214: Guide home
215: Round part
220: Assembly rod
230: Assembly nut
300: lifting unit
400: Locking unit
410: base
411: Cam Home
420: catch
421: Hook groove
422: 1st Sgt.
423: 2nd light division
424: Hook groove inclined portion
425: Seating part
430: hook
440: friction support
450: Locking driving unit
460: Catch House
461: Auxiliary guide groove
500: Alignment unit
510: upper link
520: lower link
530: rotation axis
540: First upper bracket
550: Second upper bracket
560: First lower bracket
570: Second lower bracket
580: 1st computer bolt
590: Second computer bolt

Claims (10)

Main frame mounted on the head of the pile;
a drop hammer disposed on the upper side of the pile and provided to be capable of being raised and lowered on the main frame;
a lifting unit disposed on the upper side of the main frame and configured to raise and lower the drop hammer; and
When the main frame is mounted on the pile head, it includes an alignment unit that aligns the central axis of the lifting unit and the central axis of the pile,
The drop hammer is,
A plurality of RAMs stacked along the vertical direction of the main frame; and
Includes an assembly rod for fastening a plurality of the rams,
A rounded portion is formed at a corner of the RAM disposed at the lowest side among the plurality of RAMs,
The RAM is,
Alignment holes penetrating along the vertical direction of the ram; and
Includes an alignment protrusion extending from the alignment hole,
A dynamic load test device wherein two adjacent rams among the plurality of rams are fastened and aligned through the alignment protrusion and the alignment hole.
According to paragraph 1,
The sorting unit,
an upper link coupled to the lower end of the lifting unit;
a lower link coupled to the upper end of the main frame; and
A dynamic load testing device comprising a rotation axis that couples the lower link to enable relative rotation with respect to the upper link.
According to paragraph 2,
The sorting unit,
a first upper bracket coupled to one side of the upper link;
a second upper bracket coupled to the other side of the upper link;
a first lower bracket disposed to be spaced apart from the lower side of the first upper bracket and coupled to one side of the lower link;
a second lower bracket disposed to be spaced apart from the lower side of the second upper bracket and coupled to the other side of the lower link;
a first bolt with one side coupled to the first upper bracket and the other side elastically supported by the first lower bracket; and
A dynamic load testing device comprising a second computer bolt on one side of which is coupled to the second upper bracket and the other side of which is elastically supported by the second lower bracket.
According to paragraph 2,
Dynamic load test device, wherein the upper link and the lower link are composed of a pair.
delete delete According to paragraph 1,
A dynamic load test device in which a shackle hole is formed on the alignment protrusion along the horizontal direction of the ram.
According to paragraph 1,
A dynamic load test device in which a bottom plate of a shape corresponding to the shape of the pile head is provided on the lower surface of the main frame.
According to paragraph 1,
A dynamic load test device comprising the lifting unit and a locking unit for locking or unlocking the drop hammer.
In paragraph 9
The locking unit includes a hook groove provided in the lifting unit, and a hook provided in the drop hammer and locked or unlocked in the hook groove.

Images