WO2021068342A1

WO2021068342A1 - Needle-type penetrometer suitable for concrete strength measurement

Info

Publication number: WO2021068342A1
Application number: PCT/CN2019/118059
Authority: WO
Inventors: 张明荣
Original assignee: 苏州市吴江东南建筑检测有限公司
Priority date: 2019-10-09
Filing date: 2019-11-13
Publication date: 2021-04-15
Also published as: CN110823725A

Abstract

A needle-type penetrometer, comprising a body (1), a handle (2), a hooking arm (3), a measurement needle (4), a pressing shaft (5), an elastic member (6), an adjustment member (7), and an adjustment nut (8). An accommodating cavity (11) and a penetrating hole (12) are provided in the body (1); the pressing shaft (5) penetrates through the penetrating hole (12), and the top end of the pressing shaft is provided with a limiting step (51); the elastic member (6) is provided in the accommodating cavity (11) and elastically abuts against the upper plane of the limiting step (51); the handle (2) drives the hooking arm (3) to circumferentially swing so as to control the axial displacement motion of the pressing shaft (5); the measurement needle (4) is fixed at the lower end of the pressing shaft (5); the adjustment member (7) comprises a pressing plate (71) and an adjustment rod (72); the pressing plate (71) is provided in the accommodating cavity (11) and always abuts against the elastic member (6); the adjustment rod (72) penetrates through the top wall of the accommodating cavity (11), and external threads matched with the adjustment nut (8) are formed on the side wall of the penetrating portion of the adjustment rod. Therefore, an operator only needs to rotate the adjustment nut (8) according to a specific measurement requirement, so that the compressed amount of the elastic member (6) is conveniently and quickly changed, and the downward impulse amount of the measurement needle (4) is indirectly controlled.

Description

A needle penetrometer suitable for concrete strength testing

Technical field

The invention relates to the technical field of building inspection, in particular to a needle penetrometer suitable for concrete strength inspection.

Background technique

The mortar penetration method is the main method for testing the compressive strength of masonry mortar, and it has an important position in construction site testing. The mortar penetration method is to penetrate the rigid stylus into the concrete by precisely controlling the power. It mainly includes the following two steps: nail penetration and depth measurement. Nail penetration: Use a needle penetrometer to penetrate the test nail into the tested masonry component, leave a test point on the masonry component, and leave the test hole after the test nail is pulled out, and then determine the penetration resistance according to the depth value of the measurement and control , According to this to evaluate the quality of concrete forming. In the actual operation process, the launching end of the needle penetrometer is pressed tightly on the side surface, and the elastic force of the loaded spring is used to launch the stylus at the same time, which facilitates the impact kinetic energy to penetrate the concrete.

Nowadays, a variety of models and specifications of needle penetrators have been developed for different application scenarios, but they all have the problem that the impact force of the stylus cannot be adjusted or the adjustment process is cumbersome. One of the specifications is shown in Figure 1. For the needle penetrometer, it can be known that the movement stroke of the load spring in the needle penetrometer is always kept unchanged during the process of repeatedly activating the needle penetrometer. For different application scenarios, the needle penetrometer needs to be disassembled to replace load springs with different stiffness coefficients, so that the stylus has a suitable impact force value. It can be seen that the impact force adjustment process of the above-mentioned stylus is extremely cumbersome, which greatly limits the scope of application of the needle penetrometer. In addition, a single adjustment process consumes a lot of operating time, which greatly reduces the detection speed. Therefore, technical personnel are urgently required to solve the above-mentioned problems.

Summary of the invention

The technical problem to be solved by the present invention is to provide a needle penetrometer suitable for concrete strength detection, which has a simple structure design and is convenient to adjust the impact force value of the stylus.

In order to solve the above technical problems, the present invention relates to a needle penetrometer suitable for concrete strength detection, which includes a body, a handle, a hook arm, a stylus, a pressure shaft and an elastic member. An accommodating cavity and a through hole are provided in the body. The through hole is arranged directly below the containing cavity and communicates with it. The pressure shaft is penetrated in the through hole, and a limited step is arranged on the top of the pressure shaft. The elastic member is arranged in the accommodating cavity and elastically abuts against the upper plane of the limit step. The handle is hinged on the side wall of the body, and drives the hook arm to swing circumferentially to realize the control of the axial displacement movement of the pressing shaft. The stylus is fixed at the lower end of the pressure shaft, and is driven by the elastic force of the elastic member to move downward. In addition, the needle penetrometer suitable for concrete strength testing also includes an adjusting piece and an adjusting nut. The adjusting member includes a pressing plate and an adjusting rod vertically connected with the pressing plate. The pressure plate is built in the containing cavity and always abuts against the elastic member. The adjusting rod passes through the top wall of the accommodating cavity, and the side wall of the passing part is provided with an external thread adapted to the adjusting nut.

As a further improvement of the technical solution of the present invention, the outer diameter of the pressing plate is adapted to the inner diameter of the containing cavity.

As a further improvement of the technical solution of the present invention, a plurality of graphite inlaid annular grooves are opened around the outer side wall of the pressure plate and the adjusting rod, and they are uniformly distributed along the axial direction of the adjusting member.

As a further improvement of the technical solution of the present invention, the stylus and the pressure shaft are detachably connected through a thread pair.

As a further improvement of the technical solution of the present invention, the diameter of the stylus is controlled within 3.5-5 mm, and it has a tapered striking end.

As a further improvement of the technical solution of the present invention, the elastic member is a columnar spring or an elastic rubber sleeve.

As a further improvement of the technical solution of the present invention, the above-mentioned needle penetrometer suitable for concrete strength testing further includes a supporting sleeve, which is detachably fixed to the lower end of the body, and is provided with a through hole for free passage of the stylus .

As a further improvement of the technical solution of the present invention, a titanium nitride wear-resistant coating is provided on the lower end surface of the abutment sleeve, and the thickness is controlled to be 2-2.5 μm.

Of course, as another modification of the above-mentioned technical solution, the above-mentioned abutment sleeve can also be made of cemented carbide.

By adopting the above technical solution for setting, the operator turns the adjusting nut according to the specific detection requirements, so that the adjusting member is displaced along its axial direction, that is, the amount of compression of the elastic member is changed, and the amount of impulse under the stylus is indirectly controlled. the size of. In this way, compared with the needle penetrometer with the traditional design structure, the impact force value of the stylus can be adjusted more conveniently and quickly, which effectively shortens the time required for concrete strength testing and improves the detection efficiency.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

Fig. 1 is a schematic structural diagram of a needle penetrometer suitable for concrete strength detection in the prior art.

Fig. 2 is a schematic structural diagram of a first embodiment of a needle penetrometer suitable for concrete strength detection in the present invention.

Fig. 3 is a schematic structural view of a second embodiment of a needle penetrometer suitable for concrete strength detection in the present invention.

Fig. 4 is a schematic structural diagram of a third embodiment of a needle penetrometer suitable for concrete strength detection in the present invention.

Fig. 5 is a three-dimensional schematic diagram of the adjusting member of the needle penetrometer suitable for concrete strength detection according to the present invention.

1-body; 11-accommodating cavity; 12-through hole; 2-handle; 3-hook arm; 4-stylus; 41-tapered striking end; 5-final axis; 51-limit step; 6-columnar Spring; 7-Adjusting member; 71-Pressing plate; 711-Graphite inlaid ring groove; 72-Adjusting rod; 8-Adjusting nut; 9-Locking nut; 10-Abutting sleeve.

Detailed ways

In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", etc. are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description. It does not indicate or imply that the pointed device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

In the following, the content of the present invention will be further described in detail with reference to specific examples. Figure 2 shows a schematic structural diagram of the first embodiment of the needle penetrometer suitable for concrete strength detection in the present invention, which is mainly composed of a main body 1, The handle 2, the hooking arm 3, the stylus 4, the pressure shaft 5 and the cylindrical spring 6 are composed of several parts. Wherein, a receiving cavity 11 and a through hole 12 are provided in the body 1. The through hole 12 is arranged directly below the accommodating cavity 11 and communicates with it. The pressing shaft 5 passes through the above-mentioned through hole 12, and a limit step 51 is provided at the top end thereof. The handle 2 is hinged on the side wall of the main body 1 and drives the hook arm 3 to swing circumferentially to realize the control of the axial displacement movement of the pressure shaft 5. The stylus 4 is fixed at the lower end of the pressure shaft 5, and is driven by the elastic force of the cylindrical spring 6 to move downward. In addition, what needs to be emphasized here is that the needle penetrometer suitable for concrete strength testing is additionally provided with an adjusting member 7 and an adjusting nut 8. The adjusting member 7 is composed of a pressing plate 71 and an adjusting rod 72 perpendicularly connected to the pressing plate 71. The pressing plate 71 is built in the accommodating cavity 11. The column spring 6 is also arranged in the containing cavity 11, and its two ends respectively elastically abut against the top wall of the containing cavity 11 and the upper plane of the limiting step 51. The adjusting rod 72 passes through the top wall of the accommodating cavity 11, and an external thread that matches the adjusting nut 8 is opened on the side wall of the passing part. In the actual operation process, the staff rotates the adjusting nut 8 according to the test requirements of the concrete sampled concrete, thereby driving the adjusting member 7 to move along its axial direction, that is, changing the compressed amount of the cylindrical spring 6 and indirectly controlling the test The size of the impulse under needle 4. In this way, compared with the needle penetrometer with a traditional design structure, the impact force value of the stylus 4 can be adjusted more conveniently and quickly, which effectively shortens the time required for concrete strength testing and improves the detection efficiency.

It should be noted here that, in addition to the cylindrical spring 6 described above, the elastic member used to drive the pressure shaft 5 to move downward can also be selected according to actual conditions such as gas springs, elastic rubber sleeves and other elastic elements.

As a further optimization of the above-mentioned needle penetrometer suitable for concrete strength testing, the outer diameter of the pressing plate 71 is preferably adapted to the inner diameter of the accommodating cavity 11, and the unilateral clearance is controlled within 0.5 mm, so as to ensure that the adjustment member 7 Always maintain the vertical state during the axial displacement, thereby effectively preventing the "biased" phenomenon of the elastic member.

It is known that during the reciprocating axial displacement of the adjusting member 7, the pressing plate 71 and the adjusting rod 72 will inevitably be affected by the relative friction of the body 1 and wear, thereby affecting the matching accuracy of the adjusting member 7. This in turn leads to reduced movement flexibility and accuracy. For this reason, FIG. 3 shows a schematic structural diagram of the second embodiment of the needle penetrometer suitable for concrete strength detection in the present invention, which is compared with the above-mentioned first embodiment. The difference of the method lies in that: a plurality of graphite inlaid annular grooves 711 are opened around the outer side wall of the pressure plate 71 and the adjusting rod 72, which are used to insert the lubricating graphite, and are uniformly distributed along the axial direction of the adjusting member 7 (as shown in the figure). Shown in 5). The lubricating graphite itself has excellent self-lubricating properties, which can greatly reduce the relative friction coefficient between the adjusting member 7 and the body 1, and reduce the wear rate.

Furthermore, it can also be seen from Fig. 3 that a lock nut 9 can also be provided directly above the adjusting nut 8 and used in conjunction. After the adjustment of the axial displacement movement of the adjusting member 7 is completed, the lock nut 9 is tightened in time to prevent the adjusting nut 8 from spinning during the later test process.

Furthermore, the stylus 4 and the pressure shaft 5 are preferably detachably connected through a threaded pair. In this way, when the stylus 4 is damaged or reaches the end of its service life, the replacement operation can be completed conveniently and quickly, to a certain extent Reduce the auxiliary man-hours required for testing.

Generally speaking, in order to ensure the smooth execution of the test process and the accuracy of the test results, the diameter of the above-mentioned stylus 4 should be controlled within 3.5-5 mm, and it has a tapered striking end 41.

It is known that in the process of testing, the needle penetrometer must be against the concrete member, which can easily cause abrasion on its bottom end surface. As a result, on the one hand, it is easy to cause the stylus 4 to tilt. Affects the penetration depth of the pinhole, which in turn affects the accuracy of the measurement results; on the other hand, it also affects the service life of the needle penetrometer and increases the cost of equipment procurement. In order to solve the above-mentioned technical problems, FIG. 4 shows a schematic structural diagram of a third embodiment of a needle penetrometer suitable for concrete strength detection in the present invention. Compared with the above two embodiments, the difference lies in: additional settings There is a supporting sleeve 10, which is detachably fixed to the lower end of the main body 1, and is provided with a through hole for the stylus 4 to pass freely, and the supporting sleeve 10 is required to have good abrasion resistance.

Generally speaking, it is recommended to use the following two methods to ensure good wear resistance of the supporting sleeve 10, as follows: 1) A titanium nitride wear-resistant coating is provided on the lower end of the supporting sleeve 10 (not shown in the figure) Out), the thickness is controlled within 2-2.5 μm; 2) The abutment sleeve 10 is made of cemented carbide.

The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown in this document, but should conform to the widest scope consistent with the principles and novel features disclosed in this document.

Claims

A needle penetrometer suitable for testing the strength of concrete, comprising a main body, a handle, a hook arm, a stylus, a pressure shaft, and an elastic member; an accommodation cavity and a through hole are provided in the main body; the through hole is arranged Directly below and in communication with the containing cavity; the pressure shaft penetrates through the through hole, and a limit step is provided at the top end thereof; the elastic member is arranged in the containing cavity, And it elastically abuts on the upper plane of the limit step; the handle is hinged on the side wall of the body, and drives the hook arm to swing circumferentially to realize the axial displacement movement of the pressure shaft The stylus is fixed at the lower end of the pressure shaft and moves downward under the drive of the elastic force of the elastic member. It is characterized in that it also includes an adjusting member and an adjusting nut; the adjusting member includes a pressing plate and a The pressure plate is vertically connected to the adjusting rod; the pressure plate is built in the containing cavity and always abuts against the elastic member; the adjusting rod passes through the top wall of the containing cavity, and in the passing part An external thread that matches with the adjusting nut is opened on the side wall of the device.
The needle penetrometer suitable for testing the strength of concrete according to claim 1, wherein the outer diameter of the pressing plate is adapted to the inner diameter of the containing cavity.
The needle penetrometer suitable for concrete strength testing according to claim 2, wherein a plurality of graphite inlaid annular grooves are provided around the outer side wall of the pressure plate and the adjusting rod, and are arranged along the outer wall of the adjusting rod. The adjustment pieces are uniformly distributed in the axial direction.
The needle penetrometer suitable for concrete strength testing according to claim 1, wherein the stylus and the pressure shaft are detachably connected by a thread pair.
The needle penetrometer suitable for concrete strength testing according to claim 1, wherein the diameter of the stylus is controlled within 3.5-5 mm, and it has a tapered striking end.
The needle penetrometer suitable for concrete strength testing according to claim 1, wherein the elastic member is a columnar spring or an elastic rubber sleeve.
The needle penetrometer suitable for testing the strength of concrete according to any one of claims 1 to 6, characterized in that it further comprises a butting sleeve, which is detachably fixed to the lower end of the body and is provided with There is a through hole for the stylus to pass freely.
The needle penetrometer suitable for concrete strength testing according to claim 7, characterized in that a titanium nitride wear-resistant coating is provided on the lower end surface of the abutment sleeve, and the thickness is controlled within 2-2.5 μm.
The needle penetrometer suitable for concrete strength testing according to claim 7, wherein the abutment sleeve is made of cemented carbide.