JP7565557B2 - Mold tube for forming specimens - Google Patents

Description

The present invention relates to a mold tube suitable for producing specimens for compressive strength tests made by hardening cement milk.

Compressive strength tests are mandatory for cement structures cast on-site. Specimens for compressive strength tests are prepared by filling samples of concrete, cement milk, mortar, etc. into a plastic mold tube with a bottom, as shown in the following patent document, and then allowing it to harden.

When preparing a specimen using cement milk as a sample, laitance (a low-strength area consisting of bleeding water and impurities that float to the top) is prominently formed at the upper end of the specimen during the hardening process. Conventionally, the upper end of the specimen was cut together with the mold tube in order to remove the laitance, but this required the preparation of a machine for the cutting work, making the process of removing the laitance complicated.

Japanese Patent Application Publication No. 9-145570

In light of the above circumstances, the present invention aims to provide a mold tube for forming specimens that can easily remove the laitance that occurs at the upper end of a specimen during the process of producing a cement milk specimen.

As a result of extensive investigations aimed at solving the above problems, the present inventors have arrived at the present invention as described below.
The mold tube for forming a specimen according to the first aspect of the present invention is defined as follows:
A mould tube for forming a cement milk specimen,
A specimen body forming section having a cylindrical shape with an open upper end and a closed lower end and having a molding space for a specimen therein;
A specimen forming auxiliary part is provided on the upper end side of the specimen main body forming part and expands the molding space upward,
The specimen main body forming section and the specimen forming auxiliary section are connected by a separable means.

According to the mold tube of the first aspect defined in this manner, a specimen formation auxiliary section which expands the molding space upward is provided on the upper end side of the specimen body formation section, and taking into account the laitance which occurs in the process of producing the cement milk specimen, it is possible to produce a specimen which is longer in the axial direction than conventional specimens.
Furthermore, since the specimen body forming part and the specimen body forming auxiliary part are connected by a separable means, after laitance has occurred, the specimen formation auxiliary part provided on the upper end side can be separated from the specimen body forming part to expose the laitance that has occurred at the upper end of the specimen, and the laitance can be easily removed.

The second aspect of the present invention is defined as follows:
In a first aspect, in a specified mold tube, the separable means includes an engaging portion formed on one of the specimen body forming portion and the specimen formation auxiliary portion, and an engaged portion formed on the other of the specimen body forming portion and the specimen formation auxiliary portion.
According to the mold tube of the second aspect defined in this manner, the specimen body forming portion and the specimen formation auxiliary portion can be connected by engaging the engaging portion with the engaged portion, and the specimen body forming portion and the specimen formation auxiliary portion can be separated by releasing the engagement.

The separable means can include a pin protruding outward from the cylindrical wall of the specimen body forming part, and a guide groove formed in the cylindrical wall of the specimen body forming auxiliary part that can engage with the pin, the guide groove having one end open downward (third aspect). In this way, the engagement can be released by moving the pin that engages with the guide groove relatively toward the open end of the guide groove, and the specimen body forming auxiliary part can be separated from the specimen body forming part.

The separable means may also include a pin protruding downward from the cylindrical wall of the specimen formation auxiliary part, and a protrusion protruding outward from the cylindrical wall of the specimen main body formation part, which is open upward and forms the periphery of a vertical hole into which the pin can be inserted (fourth aspect). In this way, the pin that engages with the vertical hole can be moved upward relative to the vertical hole to release the engagement, and the specimen formation auxiliary part can be separated from the specimen main body formation part.

The fifth aspect of the present invention is defined as follows:
In a first aspect, in the specified mold tube, the separable means is provided with a first weak portion formed along the upper edge of the tubular wall portion of the specimen body forming portion, and the specimen body forming portion and the specimen forming auxiliary portion are connected via the first weak portion.
According to the mold pipe of the fifth aspect thus defined, the specimen formation auxiliary portion can be separated from the specimen main body formation portion by applying a force to the first weak portion.

Here, a strip-shaped separation section can be provided in the specimen formation auxiliary section, with the first weak portion as one side in the width direction and a second weak portion formed at a certain distance from the first weak portion as the other side in the width direction (sixth aspect). In this way, the specimen formation auxiliary section can be easily separated from the specimen main body formation section by pulling the separation section provided on the specimen formation auxiliary section side outward.

FIG. 1 is a perspective view of a mold tube according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view showing the mold tube of FIG. 1 separated into a specimen main body forming portion and a specimen forming auxiliary portion. FIG. 3 shows the specimen body forming portion, where FIG. 3(A) is a front view, FIG. 3(B) is a bottom view, and FIG. 3(C) is a cross-sectional view along the CC arrows in FIG. 3(A). Figure 4(A) shows the specimen formation auxiliary part separated from the upper end of the specimen main body formation part, and Figure 4(B) shows the specimen formation auxiliary part connected to the upper end of the specimen main body formation part. FIG. 5 is a cross-sectional view of the mold tube with the specimen forming auxiliary section connected to the specimen main body forming section. FIG. 6 is a diagram for explaining a method of forming a specimen using the mold pipe of the embodiment. 7A and 7B are views showing a mold tube according to a second embodiment of the present invention, in which FIG. 7A is a front view and FIG. 7B is a cross-sectional view taken along the line BB of FIG. 7A. 8A and 8B are diagrams showing a mold tube according to a third embodiment of the present invention, in which FIG. 8A is a plan view, FIG. 8B is a front view, FIG. 8C is a side view, and FIG. 8D is a cross-sectional view taken along the line D-D of FIG. 8C. 9A to 9C are diagrams showing a modified example in which a plurality of cut-off portions are provided, in which FIG. 9A is a plan view, FIG. 9B is a front view, and FIG. 9C is a rear view.

The following describes an embodiment of the present invention with reference to the drawings.

First Embodiment
Fig. 1 is a perspective view of a mold tube according to a first embodiment of the present invention. In the following description, the up and down of the mold tube refers to the up and down of the mold tube when the mold tube is placed on the ground or the like with an opening 28 at one end facing upward as shown in Fig. 1.
In the figure, reference numeral 1 denotes a mold tube for forming a specimen made of hardened cement milk, and has an overall cylindrical shape with a bottom. The mold tube 1 has a separate specimen body forming section 2 and specimen forming auxiliary section 4, which are connected so as to be separable.

FIG. 2 is a cross-sectional view showing the mold tube 1 separated into a specimen main body forming section 2 and a specimen forming auxiliary section 4.
As shown in Fig. 2, the specimen body forming part 2 is a cylindrical body made of synthetic resin having an opening 12 at the upper end, and includes a cylindrical wall part 11 extending in the vertical direction, and a flange part 13 protruding inward from the lower end of the cylindrical wall part 11. A bottom plate 16 having a circular shape in a plan view is provided on the flange part 13 so as to cover a hole 15 at the center of the lower end. The bottom plate 16 is made of synthetic resin or metal. The contact point between the bottom plate 16 and the flange part 13 can be treated by welding, bonding, or the like to prevent leakage of cement milk.
Inside the specimen body forming portion 2 , a cylindrical molding space 18 is formed, which is defined by the inner circumferential surface 17 of the cylindrical wall portion 11 and the upper surface of the bottom plate 16 .

As shown in Figure 3, a band-shaped separation portion 20 is formed in the specimen body forming portion 2. The separation portion 20 is defined by two grooves 21, 21 that extend from the edge of the upper end opening 12 to the lower end on the outer surface of the tube wall portion 11, and two grooves 22, 22 that extend radially on the lower surface of the flange portion 13 (see Figure 3 (B)). In the area where these grooves 21 and 22 are formed, as shown in the partially enlarged view of Figure 3 (C), a fragile portion 25 that is thinner than other portions and easily breakable is formed.

As shown in Figures 3(A) and 3(B), a plate-shaped leg piece 23 protruding outward is formed on the lower end side of the separation portion 20. The leg piece 23 functions to prevent the specimen body forming portion 2 from falling over when it is placed on the ground with its opening 12 facing upward, and can also be used as a gripping piece when cutting off the separation portion 20. In this example, the band-shaped separation portion 20 is provided on both diametrical sides of the specimen body forming portion 2.

At the upper part of the tube wall portion 11, at a position 90° circumferentially different from the separation portion 20, a pin 27 is formed that protrudes outward from the tube wall portion 11. Such pin 27 constitutes a separable means for separably connecting the specimen main body forming portion 2 and the specimen forming auxiliary portion 4.

Next, the specimen forming auxiliary part 4 is attached to the upper end side of the specimen body forming part 2 as shown in Figures 1 and 2, and expands the molding space 18 of the specimen body forming part 2 upward.

The specimen formation auxiliary part 4 is a cylindrical body made of synthetic resin. As shown in FIG. 2, the inner peripheral surface of the specimen formation auxiliary part 4 is provided with an upper end side inner peripheral surface 29, a lower end side inner peripheral surface 30, and a downward step surface 31 connecting these inner peripheral surfaces, and the inner diameter D2 on the lower end side is larger than the inner diameter D1 on the upper end side of the tube wall part 33. In detail, the inner diameter D1 on the upper end side is the same as the inner diameter of the tube wall part 11 of the specimen main body formation part 2, and the inner diameter D2 on the lower end side is the same as or slightly larger than the outer diameter of the tube wall part 11 of the specimen main body formation part 2.

In addition, guide grooves 34 that can engage with the pins 27 of the specimen body forming part 2 are provided on both sides of the tube wall part 33 in the diametric direction. As shown in FIG. 4(A), the guide grooves 34 are composed of a first guide groove 34a that extends in the vertical direction and has its lower end open downward, and a second guide groove 34b that extends in the circumferential direction from the upper end of the first guide groove 34a. When connecting with the specimen body forming part 2, the lower end of the specimen formation auxiliary part 4 is fitted externally to the upper end of the specimen body forming part 2, and the pins 27 of the specimen body forming part 2 inserted into the guide groove 34 from the open end of the first guide groove 34a are engaged with the second guide groove 34b as shown in FIG. 4(B), so that the specimen formation auxiliary part 4 is connected to the specimen body forming part 2 at a predetermined position.

As shown in FIG. 5, in the mold tube 1 with the specimen body forming section 2 and the specimen body forming auxiliary section 4 connected, the upper end inner circumferential surface 29 of the specimen forming auxiliary section 4 is flush with the inner circumferential surface 17 of the specimen body forming section 2, and the molding space 18 is expanded upward along the upper end inner circumferential surface 29. As a result, it is possible to produce a specimen that is longer in the axial direction than conventional specimens, taking into account the laitance formed at the upper end of the specimen.

Next, a method of forming a specimen using the mold tube 1 will be described. First, as shown in FIG. 6(I), the molding space 18 inside the mold tube 1, in which the specimen body forming part 2 and the specimen forming auxiliary part 4 are connected, is filled with cement milk S as a sample. After a predetermined time (e.g., 24H) has elapsed and laitance L has occurred at the upper end of the specimen K, as shown in FIG. 6(II), the pin 27 of the specimen body forming part 2 and the guide groove 34 of the specimen forming auxiliary part 4 are disengaged, and the specimen forming auxiliary part 4 is separated from the specimen body forming part 2. In this way, the main body of the specimen K is held within the specimen body forming part 2 of the mold tube 1, while the laitance L occurring at the upper end of the specimen K is exposed and removed (see FIG. 6(III)). Then, after a predetermined time has elapsed, the separation portion 20 of the specimen body forming portion 2 is cut vertically as shown by the two-dot chain line in FIG. 6 (III), and the specimen body forming portion 2 is disassembled, allowing the cylindrical body of the specimen K to be removed.

As described above, according to the mold tube 1 of this embodiment, a specimen formation auxiliary section 4 that expands the molding space 18 upward is provided on the upper end side of the specimen body formation section 2, and it is possible to produce a specimen that is longer in the axial direction than conventional specimens, taking into account the laitance that occurs in the process of producing a cement milk specimen.
Furthermore, since the specimen body forming section 2 and the specimen body forming auxiliary section 4 are connected by a separable means, by separating the specimen body forming auxiliary section 4 provided on the upper end side from the specimen body forming section 2, the laitance generated at the upper end section of the specimen can be exposed, and the laitance can be easily removed.

In the molded tube 1 of this embodiment, the separation means includes a pin 27 protruding outward from the tube wall 11 of the specimen body forming section 2, and a guide groove 34 formed in the tube wall 33 of the specimen body forming auxiliary section 4 and capable of engaging with the pin 27. One end of the guide groove 34 is open downward, so that the engagement can be released by moving the pin 27 that engages with the guide groove 34 relatively toward the open end of the guide groove 34, and the specimen body forming auxiliary section 4 can be separated from the specimen body forming section 2.

Second Embodiment
7 shows a molded pipe 1B according to a second embodiment of the present invention. The molded pipe 1B has a separate specimen body forming section 2B and a specimen forming auxiliary section 4B, which are separably connected to each other. Among these components, components common to the molded pipe 1 according to the first embodiment are indicated by the same reference numerals, and description thereof will be omitted.

In this example, pins 45 protruding downward from the lower end of the cylindrical wall portion 33 are formed at three different circumferential positions on the cylindrical wall portion 33 of the specimen formation auxiliary portion 4B.
On the other hand, a protrusion 40 is formed on the cylindrical wall 11 of the specimen main body forming part 2B at a position corresponding to the pin 45, protruding outward from the cylindrical wall 11, and this protrusion 40 forms the periphery of a vertical hole 42 that is open upward and downward. The vertical hole 42 formed by the protrusion 40 allows the pin 45 to be inserted.

In this way, this example is provided with a pin 45 of the specimen formation auxiliary part 4B and a protrusion 40 of the specimen body formation part 2B as the separation means. By inserting the pin 45 into the vertical hole 42, the specimen formation auxiliary part 4 is connected to the specimen body formation part 2 at a predetermined position. On the other hand, by pulling out the pin 45 that engages with the vertical hole 42 upward, the engagement is released and the specimen formation auxiliary part 4B can be separated from the specimen body formation part 2B. Note that the axial fixing force of the pin 45 in this example can be adjusted by the fit dimension between the pin 45 and the vertical hole 42.

Third Embodiment
FIG. 8 shows a mold tube 1C according to a third embodiment of the present invention.
The mold pipe 1C includes a specimen body forming section 2C and a specimen formation auxiliary section 4C provided on the upper end side of the specimen body forming section 2C. Among these components, components common to the components of the mold pipe 1 according to the first embodiment are indicated by the same reference numerals, and description thereof will be omitted.

In this example, the specimen body forming portion 2C and the specimen formation auxiliary portion 4C are connected via a first weak portion 53 (the first weak portion 53 located at the same position as the first groove 51) formed along the upper edge 50 of the tubular wall portion 11 of the specimen body forming portion 2C.
8(B) and 8(C), a first groove 51 is formed at a position corresponding to the edge 50 at the upper end of the specimen main body forming portion 2C. The first groove 51 extends from the center position in the left-right direction to the left in Fig. 8(B) and is formed around the entire circumference of the edge 50, and then extends upward to reach the upper end of the specimen formation auxiliary portion 4C.

Also, a second groove 52 is formed at a position on the side of the specimen formation auxiliary section 4C, a certain distance away from the first groove 51. The first groove 51 and the second groove 52 have a substantially V-shaped cross section, as shown in Fig. 8(D) . In the area where the first groove 51 and the second groove 52 are formed, a first fragile part 53 and a second fragile part 54 are formed, which are thinner and more fragile than other parts.
As a result, in the specimen formation auxiliary section 4C, a band-shaped detachment section 55 is formed, with the first weak section 53 as one side in the width direction and the second weak section 54 as the other side in the width direction.

As shown in FIG. 8(A), a plate-shaped gripping piece 57 is formed on the upper end side of the separation portion 55, protruding outward from the tube wall portion 33. When separating the separation portion 55 from the specimen main body forming portion 2C and the specimen forming auxiliary portion 4C, the gripping piece 57 is grasped with fingertips or pliers, and pulled outward as shown by the two-dot chain line in FIG. 8(C), whereby the separation portion 55 is separated along the grooves 51 and 52 (i.e., along the fragile portions 53 and 54).

As described above, the molded pipe 1C of this embodiment has a first fragile portion 53 formed along the upper edge 50 of the specimen body forming portion 2C as a means for separably connecting the specimen body forming portion 2C and the specimen body forming auxiliary portion 4C, and the specimen body forming portion 2C and the specimen body forming auxiliary portion 4C are connected via the first fragile portion 53. Therefore, by applying a force to the first fragile portion 53, the specimen body forming auxiliary portion 4C can be separated from the specimen body forming portion 2C.

In the molded pipe 1C of this embodiment, the specimen formation auxiliary portion 4C is provided with a strip-shaped separation portion 55, with the first weak portion 53 as one side in the width direction and the second weak portion 54 formed at a fixed distance from the first weak portion 53 as the other side in the width direction, and by pulling the separation portion 55 outward, the specimen formation auxiliary portion 4C can be easily separated from the specimen main body formation portion 2C.

It is also possible to provide multiple separation sections in the circumferential direction in the molded pipe 1C. Figure 9 shows a modified example of the separation section 55 in the molded pipe 1C. In this modified example, a first separation section 55a and a second separation section 55b are provided as the separation sections, and each of them partially separates the specimen formation auxiliary section 4C from the specimen main body formation section 2C over a length equivalent to half the circumference of the tube wall section 11 (the length indicated by the arrow line in Figure 9 (A)).

Although the embodiments of the present invention have been described in detail above, the present invention is in no way limited to these descriptions. Various modifications that do not deviate from the scope of the claims and that can be easily conceived by a person skilled in the art are also included in this invention.

Reference Signs List 1, 1B, 1C...Mold tube 2, 2B, 2C...Specimen main body forming portion 4, 4B, 4C...Specimen forming auxiliary portion 11...Cylinder wall portion 18...Molding space 27, 45...Pin 33...Cylinder wall portion 34...Guide groove 40...Protrusion portion 42...Vertical hole 50...Edge 53...First weak portion 54...Second weak portion 55...Separation portion

Claims (5)

A mould tube for forming a cement milk specimen,
A specimen body forming section having a cylindrical shape with an open upper end and a closed lower end and having a molding space for the specimen therein;
A specimen forming auxiliary part is provided on the upper end side of the specimen main body forming part and expands the molding space upward,
A mold tube for forming a specimen , in which the specimen main body forming section and the specimen forming auxiliary section are connected by a separable means,
The separable means includes:
An engagement portion formed on either the specimen main body forming portion or the specimen forming auxiliary portion;
An engaged portion formed on the other of the specimen main body forming portion and the specimen forming auxiliary portion;
A mold tube for forming a specimen, comprising: The separable means includes:
A pin protruding outward from a cylindrical wall portion of the specimen body forming portion;
A guide groove is formed in a cylindrical wall portion of the specimen formation auxiliary portion, the guide groove being engageable with the pin, and one end of the guide groove is open downward;
The mold tube for forming a specimen according to claim 1 , comprising: The separable means includes:
A pin protruding downward from a cylindrical wall portion of the specimen formation auxiliary portion;
a protrusion protruding outward from a cylindrical wall portion of the specimen body forming portion, the protrusion forming a periphery of a vertical hole that is open upward and into which the pin can be inserted;
The mold tube for forming a specimen according to claim 1 , comprising: A mould tube for forming a cement milk specimen,
A specimen body forming section having a cylindrical shape with an open upper end and a closed lower end and having a molding space for the specimen therein;
A specimen forming auxiliary part is provided on the upper end side of the specimen main body forming part and expands the molding space upward,
A mold tube for forming a specimen, in which the specimen main body forming section and the specimen forming auxiliary section are connected by a separable means ,
The separable means includes a first weak portion formed along an edge of an upper end of the cylindrical wall portion of the specimen main body forming portion,
A mold tube for forming a specimen, in which the specimen main body forming portion and the specimen forming auxiliary portion are connected via the first weak portion. The mold tube for forming specimens as described in claim 4, wherein the specimen formation auxiliary portion has a band -shaped separation portion having the first weak portion as one side in the width direction and a second weak portion formed a certain distance away from the first weak portion as the other side in the width direction.

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