Forming die and tension testing device

Abstract

The invention relates to tensile strength testing of mine filling bodies, in particular to a forming die and a tensile force testing device. The forming mold comprises a left half dumbbell mold, a right half dumbbell mold, a baffle and a bottom plate; the baffle is located between the left half dumbbell mold and the right half dumbbell mold, and the left half dumbbell mold, the baffle, the right half dumbbell mold and the second baffle are sequentially connected to form a cylindrical structure; the bottom plate is located at one end of the cylindrical structure to form a forming cavity. And the baffle is detachably connected with the bottom plate, the left half dumbbell mold and the right half dumbbell mold. The tension testing device comprises a fixed tension assembly and a movable tension assembly; the fixed tension assembly is used for connecting the left half dumbbell mold; the movable tension assembly is used for connecting the right half dumbbell mold. The testing device is mainly used for testing through the horizontal tension device, and the influence of the gravity of the sample and the device on the tensile strength test can be reduced to the greatest extent. The test piece is directly poured in the forming cavity, and the forming section is the test section, so that the test cost can be reduced to the greatest extent, and unnecessary experimental material waste is avoided.

Description

Technical Field

[0001] This application relates to the tensile strength test of mine backfill, and particularly to a forming mold and a tensile test device. Background Art

[0002] The tensile strength of mine backfill is an important parameter for evaluating its structural stability. At present, indirect methods (such as the splitting method) are mostly used for tensile strength tests, but there are problems such as large errors and complex operations.

[0003] Although the direct tensile method is more accurate, the existing devices generally have the following defects:

[0004] 1. Gravity interference: The self-weight of the specimen and the mold during vertical stretching causes uneven stress.

[0005] 2. End effect: Stress concentration occurs at the ends of the specimen, making it difficult to reflect the true tensile strength.

[0006] 3. Material waste: Traditional I-shaped specimens require a large amount of filling materials, resulting in high costs.

[0007] 4. Poor adaptability: Existing molds cannot meet the forming and testing requirements of porous and low-strength backfill.

[0008] Currently, there is no standardized test device that can effectively solve the above problems. There is an urgent need for a new type of test device to improve the test accuracy and efficiency. Summary of the Invention

[0009] In a first aspect, the present invention provides a forming mold and a tensile test device for casting specimens and assisting in the tensile test of specimens, including a left half dumbbell mold, a right half dumbbell mold, baffles, and a bottom plate;

[0010] The baffles are arranged between the left half dumbbell mold and the right half dumbbell mold, and the number of the baffles is two. The left half dumbbell mold, the baffles, the right half dumbbell mold, and the second baffle are sequentially connected to form a cylindrical structure;

[0011] The bottom plate is arranged at one end of the cylindrical structure, so that a forming cavity is formed inside the cylindrical structure, and the forming cavity is used for casting the specimen;

[0012] The connection between the baffle and the left half dumbbell mold and the right half dumbbell mold is detachable;

[0013] The connection between the bottom plate and the left half dumbbell mold and the right half dumbbell mold is detachable.

[0014] In an alternative embodiment, the detachable connection method is bolt connection.

[0015] In an alternative embodiment, the left half dumbbell mold includes a positioning section and a connecting section;

[0016] The positioning section is provided at one end of the connecting section, and the connecting section is used to connect the baffle or the specimen.

[0017] In an alternative embodiment, after the positioning section and the connecting section are connected, a T-shaped structure is formed.

[0018] In an alternative embodiment, one end of the left half dumbbell mold close to the right half dumbbell mold and one end of the right half dumbbell mold close to the left half dumbbell mold both have bonding sections for connecting the specimen after the baffle and the bottom plate are disassembled.

[0019] In a second aspect, the present invention provides a tensile testing device for applying a tensile force to the molding die according to any one of the foregoing embodiments, including a fixed tensile component and a moving tensile component;

[0020] The fixed tensile component is used to connect the left half dumbbell mold and fix the left half dumbbell mold;

[0021] The moving tensile component is used to connect the right half dumbbell mold and drive the right half dumbbell mold to move to apply a tensile force to the specimen.

[0022] In an alternative embodiment, the fixed tensile component includes an upper clamping plate, a lower clamping plate, a tensile connection section and a connecting rod;

[0023] The upper clamping plate has at least three upper connection holes, and the lower clamping plate is correspondingly provided with lower connection holes, and the connecting rod passes through the upper connection holes and the lower connection holes;

[0024] One end of the tensile connection section is arranged between the upper clamping plate and the lower clamping plate and is connected to one of the connecting rods;

[0025] Among the other connecting rods, at least two connecting rods can block and position the left half dumbbell mold to realize the connection between the fixed tensile component and the left half dumbbell mold.

[0026] In an alternative embodiment, the end of the tensile connection section arranged between the upper clamping plate and the lower clamping plate abuts against the end of the left half dumbbell mold.

[0027] In an alternative embodiment, a connection nut, a fixed end cap or a fixed pin is arranged on the connecting rod for realizing the axial positioning of the connecting rod.

[0028] In an alternative embodiment, the moving tensile component has the same structure as the fixed tensile component, and the moving tensile component and the fixed tensile component are symmetrically arranged.

[0029] The embodiments of the present application have the following beneficial effects:

[0030] This device mainly conducts tests through a horizontal tensile testing device, which can minimize the influence of the gravity of the specimen and the device on the tensile strength test.

[0031] The specimen is directly poured into the forming cavity of the forming die, and the forming section is the test section, which can minimize the test cost and avoid unnecessary waste of experimental materials.

[0032] The length of the forming section is relatively long, which can withstand a large tensile cross-section, avoid the end effect in the tensile strength test, and is suitable for forming specimens with low tensile strength, such as mine backfill, ensuring the accuracy of the tensile strength test and having a high technical matching with the backfill material. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the protection scope of the present application. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0034] Figure 1 Shows a top view of the forming die provided by the embodiment of the present application;

[0035] Figure 2 Shows a three-dimensional structural schematic diagram of the forming die provided by the embodiment of the present application;

[0036] Figure 3 Shows a three-dimensional structural schematic diagram of the tensile testing device provided by the embodiment of the present application;

[0037] Figure 4 Shows a reference diagram of the use state of the tensile testing device provided by the embodiment of the present application.

[0038] Main element symbol description: 1 - left half dumbbell die; 2 - baffle; 3 - right half dumbbell die; 4 - connection hole; 5 - bottom plate; 6 - upper clamping plate; 7 - lower clamping plate; 8 - tensile connection section; 9 - connecting rod. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments.

[0040] The components of the embodiments of the present application that are usually described and illustrated in the accompanying drawings herein can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application claimed, but merely represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present application.

[0041] Hereinafter, the terms "comprising", "having" and their cognates that can be used in various embodiments of the present application are only intended to represent specific features, numbers, steps, operations, elements, components or combinations of the foregoing items, and should not be construed as first excluding the existence of one or more other features, numbers, steps, operations, elements, components or combinations of the foregoing items or the possibility of adding one or more features, numbers, steps, operations, elements, components or combinations of the foregoing items.

[0042] In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance.

[0043] Unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the various embodiments of the present application belong. The terms (such as those defined in a commonly used dictionary) will be interpreted as having the same meaning as the contextual meaning in the relevant technical field and should not be interpreted as having an idealized or overly formal meaning unless clearly defined in the various embodiments of the present application.

[0044] The following Figure 1 to Figure 4 , some embodiments of the present application will be described in detail. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0045] In a first aspect, the present invention provides a forming mold for casting specimens and assisting in the tensile test of specimens. As Figure 1 and Figure 2 shown, it includes a left semi-dumbbell mold 1, a right semi-dumbbell mold 3, baffles 2 and a bottom plate 5; the baffles 2 are arranged between the left semi-dumbbell mold 1 and the right semi-dumbbell mold 3, and the number of the baffles 2 is two. The left semi-dumbbell mold 1, the baffle 2, the right semi-dumbbell mold 3 and the second baffle 2 are sequentially connected to form a cylindrical structure; the bottom plate 5 is arranged at one end of the cylindrical structure, so that a forming cavity is formed inside the cylindrical structure, and the forming cavity is used for casting the specimen; the connection between the baffle 2 and the left semi-dumbbell mold 1 and the right semi-dumbbell mold 3 is detachable; the connection between the bottom plate 5 and the left semi-dumbbell mold 1 and the right semi-dumbbell mold 3 is detachable.

[0046] In this embodiment, a three-dimensional rectangular coordinate system as shown in Figure 2 is established, where the length direction of the forming die is the x-direction, the width direction is the y-direction, and the thickness direction is the z-direction.

[0047] Specifically, in this embodiment, the left half dumbbell mold 1, the baffle 2, and the right half dumbbell mold 3 are arranged in sequence along the x-direction, the two baffles 2 are arranged along the y-direction, and the left half dumbbell mold 1, the baffle 2, and the right half dumbbell mold 3 are all in the z-direction of the bottom plate 5.

[0048] The left half dumbbell mold 1, the baffle 2, the right half dumbbell mold 3, and the bottom plate 5 jointly enclose a forming cavity, and a test specimen is obtained by pouring into the forming cavity.

[0049] In this embodiment, after pouring, the position of the specimen is the test section. After connecting the specimen with the left half dumbbell mold 1 and the right half dumbbell mold 3, a tensile force is applied to the left half dumbbell mold 1 or the right half dumbbell mold 3, so as to horizontally stretch the specimen and achieve the purpose of horizontal tensile force testing.

[0050] Specifically, in this embodiment, both the left half dumbbell mold 1 and the right half dumbbell mold 3 are made of materials with relatively high strength, and the strength of the left half dumbbell mold 1 and the right half dumbbell mold 3 during the tensile force test can be higher than that of the test section to avoid being damaged prior to the test section.

[0051] More specifically, in this embodiment, after pouring, the baffle 2 and the bottom plate 5 are disassembled, and the poured specimen is fixedly connected with the left half dumbbell mold 1 and the right half dumbbell mold 3, and then a tensile force is applied to the left half dumbbell mold 1 or the right half dumbbell mold 3, so as to horizontally stretch the specimen and achieve the purpose of horizontal tensile force testing.

[0052] In an alternative embodiment, the detachable connection method is a bolt connection.

[0053] In this embodiment, connection holes 4 are provided on both the left half dumbbell mold 1 and the right half dumbbell mold 3, corresponding connection holes 4 are provided on the bottom plate 5, and after the bolts pass through the connection holes 4 on the bottom plate 5 and the left half dumbbell mold 1 or the right half dumbbell mold 3, they are fixed by nuts to realize the fixation of the bottom plate 5.

[0054] Connection holes 4 are provided on the baffle 2, and the connection holes 4 on the bottom plate 5 are arranged corresponding to the connection holes 4 on the baffle 2. After the bolts pass through the connection holes 4 on the bottom plate 5 and the baffle 2, they are fixedly connected by nuts.

[0055] It should be noted that in this embodiment, the detachable connection method is bolt connection, but it is not limited to bolt connection only. It can also be other types of fixed connection methods, such as snap connection, etc., as long as the connection strength and connection stability between the left half dumbbell mold 1, the right half dumbbell mold 3, the baffle 2, and the bottom plate 5 can be ensured.

[0056] In an alternative embodiment, the left half dumbbell mold 1 includes a positioning section and a connecting section; the positioning section is provided at one end of the connecting section, and the connecting section is used to connect the baffle 2 or the specimen.

[0057] In this embodiment, after the connecting section is connected to the baffle 2 or the specimen, positioning is performed through the positioning section, so that the left half dumbbell mold 1 can position the specimen, thereby ensuring the stability of positioning during the tensile test.

[0058] In this embodiment, the positioning section is used to position the position of the left half dumbbell mold 1 to ensure its stability during the experiment.

[0059] In this embodiment, the left half dumbbell mold 1 and the right half dumbbell mold 3 have the same structure and are symmetrically arranged.

[0060] In an alternative embodiment, after the positioning section and the connecting section are connected, a T-shaped structure is formed.

[0061] Specifically, in this embodiment, the width of the positioning section is greater than the width of the connecting section, so that after the positioning section and the connecting section are connected, a T-shaped structure is formed.

[0062] More specifically, in this embodiment, the positioning section and the connecting section are an integral structure.

[0063] It can be understood that in this embodiment, the setting method of the positioning section is a T-shaped structure, but it is not limited to this setting method only. Positioning holes can also be provided on the positioning section, and the positioning of the left half dumbbell mold 1 or the right half dumbbell mold 3 can be achieved through structures such as positioning pins. That is to say, as long as the positioning of the left half dumbbell mold 1 or the right half dumbbell mold 3 can be achieved.

[0064] In an alternative embodiment, both the end of the left half dumbbell mold 1 close to the right half dumbbell mold 3 and the end of the right half dumbbell mold 3 close to the left half dumbbell mold 1 have bonding sections for connecting the specimen after the baffle 2 and the bottom plate 5 are disassembled.

[0065] Specifically, in this embodiment, the bonding section mainly bonds the specimens that have been preliminarily consolidated in the forming grooves of the left and right half dumbbells through high-strength glue, so as to prevent this section from slipping first during the tensile strength test and making the test impossible.

[0066] In this embodiment, the left half dumbbell mold 1, the test section, and the right half dumbbell mold 3 are arranged in sequence along the x direction. As shown in the figure, the program mold provided in this embodiment is suitable for manufacturing filling body specimens with a long test section, multiple pores, and low strength.

[0067] During the tensile strength test, the tensile cross-section (minimum cross-section) of the specimen can fall within the test section. When the filling body is porous and has low strength inside, the test section is long enough, making it easier to detect the strength and ensuring the accuracy of the test results. This solves the problem in the prior art that the tensile cross-section (minimum cross-section) of the specimen made by the test mold is small, and the length of the formed specimen is short, which is not suitable for manufacturing mine filling body specimens with the characteristics of multiple pores and low strength, and has poor technical matching with the filling body material.

[0068] In a second aspect, the present invention provides a tensile testing device for applying tensile force to the forming mold according to any one of the foregoing embodiments, as Figure 3 and Figure 4 shown, including a fixed tensile force component and a moving tensile force component; the fixed tensile force component is used to connect the left half dumbbell mold 1 and fix the left half dumbbell mold 1; the moving tensile force component is used to connect the right half dumbbell mold 3 and drive the right half dumbbell mold 3 to move to apply tensile force to the specimen.

[0069] The testing device provided in the embodiment of the present invention is used for actual testing of tensile strength. As Figure 4 shown in the coordinate system, it is assembled along the x direction, successively including a fixed tensile force component, a forming mold, and a moving tensile force component. Based on this tensile testing device, referring to the direct shear experiment, the fixed tensile force component is fixed, and then tensile force is applied to the moving tensile force component until the test section is damaged, and the test ends.

[0070] In an optional embodiment, the fixed tensile force component includes an upper clamping plate 6, a lower clamping plate 7, a tensile connection section 8, and a connecting rod 9; there are at least three upper connection holes 4 on the upper clamping plate 6, and corresponding lower connection holes 4 are provided on the lower clamping plate 7; the connecting rod 9 passes through the upper connection holes 4 and the lower connection holes 4; one end of the tensile connection section 8 is arranged between the upper clamping plate 6 and the lower clamping plate 7 and is connected to one of the connecting rods 9; among the other connecting rods 9, at least two connecting rods 9 can block and position the left half dumbbell mold 1 to realize the connection between the fixed tensile force component and the left half dumbbell mold 1.

[0071] In this embodiment, taking Figure 2The relative positions are introduced as follows. The upper clamping plate 6, the positioning section or the tension connection section 8, and the lower clamping plate 7 are sequentially arranged along the z direction. After the connecting rod 9 passes through the upper clamping plate 6, the tension connection section 8, and the lower clamping plate 7 in sequence, it is fixed by a nut. After the other two connecting rods 9 connect the upper clamping plate 6 and the lower clamping plate 7, they can position the positioning section inserted between the upper clamping plate 6 and the lower clamping plate 7 to prevent the positioning section from detaching between the upper clamping plate 6 and the lower clamping plate 7, and improve the connection stability of the positioning section.

[0072] In an alternative embodiment, the tension connection section 8 is arranged at the end between the upper clamping plate 6 and the lower clamping plate, and abuts against the end of the left half dumbbell mold 1.

[0073] In this embodiment, when the tension connection section 8 abuts against the end of the left half dumbbell mold 1, the tension connection section 8 can be rotationally positioned by the left half dumbbell mold 1 to avoid the shaking of the tension connection section 8 during the experiment, thereby ensuring the accuracy of the experimental results.

[0074] At the same time, the setting method of the right half dumbbell mold 3 is the same as the setting direction of the left half dumbbell mold 1, opposite in direction, and symmetrically arranged.

[0075] In an alternative embodiment, a connection nut, a fixed end cap or a fixed pin is arranged on the connecting rod 9 for realizing the axial positioning of the connecting rod 9.

[0076] In this embodiment, the connecting rod 9 can be positioned by the above-mentioned connection nut, fixed end cap or fixed pin, so as to ensure the stability of the connecting rod 9.

[0077] It should be noted that the positioning method of the connecting rod 9 can be the above several, but it is not limited to these several methods, as long as it can realize the stable positioning of the connecting rod 9.

[0078] In an alternative embodiment, the moving tension assembly has the same structure as the fixed tension assembly, and the moving tension assembly and the fixed tension assembly are symmetrically arranged.

[0079] The using process of the device provided in this embodiment is as follows:

[0080] Mold installation.

[0081] Place the bottom plate 5 on the horizontal ground, align the baffle 2 and the bottom plate 5 according to the screw holes and the fixing holes. At the same time, adjust the direction so that the two baffles 2 are symmetrical. After the screw passes through the bottom plate 5, connect the bottom plate 5 with the left half dumbbell mold 1 and the right half dumbbell mold 3, and tighten the structure into one body by rotating the screw to complete the mold installation.

[0082] Pour the specimen.

[0083] The equipped test mold is as Figure 1As shown. At this time, pouring starts in the forming cavity according to the designed pouring method.

[0084] Disassemble the mold.

[0085] After the specimen pouring is completed and meets the designed disassembly conditions, disassemble the mold, loosen the bolts in sequence, take out the two baffles 2 and the bottom plate 5, and bond the bonding ends on both sides of the specimen with high-strength glue.

[0086] Install the tensile test device.

[0087] According to Figure 2 Install the left and right tensile test devices in the z direction as shown.

[0088] Fix the left tensile test device and apply a tensile force to the right tensile test device. At this time, the tensile force is transmitted to the specimen test section through the tensile test device and the semi-dumbbell mold, so as to achieve the purpose of testing its tensile strength.

[0089] The embodiments of the present application have the following beneficial effects:

[0090] This device mainly conducts tests through the horizontal tensile device, which can minimize the influence of the gravity of the specimen and the device on the tensile strength test.

[0091] Pour the specimen directly in the forming cavity of the forming mold, and the forming section is the test section, which can minimize the test cost and avoid unnecessary waste of experimental materials.

[0092] The length of the forming section is relatively long, which can withstand a large tensile cross-section, can avoid the end effect in the tensile strength test, is suitable for forming specimens with low tensile strength, such as mine backfill, ensures the accuracy of the tensile strength test, and has a high technical matching with the backfill material.

[0093] In several embodiments provided by the present application, it should be understood that the disclosed device and method can also be implemented in other ways. The device embodiments described above are only illustrative.

[0094] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present application should be covered within the protection scope of the present application.

Claims

1. A forming mold for casting specimens and assisting in the tensile test of specimens, characterized in that, It includes a left semi dumbbell mold, a right semi dumbbell mold, baffles and a bottom plate; The baffles are located between the left semi dumbbell mold and the right semi dumbbell mold, and the number of the baffles is two. The left semi dumbbell mold, the baffles, the right semi dumbbell mold and the second baffle are connected in sequence to form a cylindrical structure; The bottom plate is located at one end of the cylindrical structure, so that a forming cavity is formed inside the cylindrical structure, and the forming cavity is used for pouring specimens; The connection between the baffles and the left semi dumbbell mold and the right semi dumbbell mold is detachable; The connection between the bottom plate and the left semi dumbbell mold and the right semi dumbbell mold is detachable.

2. The molding die according to claim 1, wherein The detachable connection method is bolt connection.

3. The molding die according to claim 1, wherein The left semi dumbbell mold includes a positioning section and a connecting section; The positioning section is arranged at one end of the connecting section, and the connecting section is used for connecting the baffle or the specimen.

4. The molding die according to claim 3, characterized in that, After the positioning section and the connecting section are connected, a T-shaped structure is formed.

5. The molding die according to claim 1, characterized in that, One end of the left semi dumbbell mold close to the right semi dumbbell mold and one end of the right semi dumbbell mold close to the left semi dumbbell mold both have bonding sections, which are used for connecting the specimen after the baffle and the bottom plate are disassembled.

6. A tensile test device for applying a tensile force to the molding die according to any one of claims 1-5, characterized in that, It includes a fixed tension component and a movable tension component; The fixed tension component is used for connecting the left semi dumbbell mold to fix the left semi dumbbell mold; The movable tension component is used for connecting the right semi dumbbell mold and is used for driving the right semi dumbbell mold to move to apply tension to the specimen.

7. The tensile testing device according to claim 6, characterized in that, The fixed tension component includes an upper clamping plate, a lower clamping plate, a tension connecting section and a connecting rod; There are at least three upper connection holes on the upper clamping plate, and corresponding lower connection holes are arranged on the lower clamping plate. The connecting rod passes through the upper connection hole and the lower connection hole; One end of the tension connecting section is arranged between the upper clamping plate and the lower clamping plate and is connected to one of the connecting rods; Among the other connecting rods, at least two connecting rods can block and position the left semi dumbbell mold to realize the connection between the fixed tension component and the left semi dumbbell mold.

8. The tensile testing device according to claim 7, wherein, The end of the tension connecting section arranged between the upper clamping plate and the lower clamping plate abuts against the end of the left semi dumbbell mold.

9. The tensile testing device according to claim 7, characterized in that, A connection nut, a fixed end cap or a fixed pin is arranged on the connecting rod to realize the axial positioning of the connecting rod.

10. The test tensile force device according to claim 6, wherein, The structure of the movable tension component is the same as that of the fixed tension component, and the movable tension component and the fixed tension component are symmetrically arranged.

Images