JP2010048029A - Improved ground testing method and unsolidified sample collector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an improved ground testing method capable of speedily verifying the quality of improved ground and facilitating rework to be executed in the case that the quality of improved ground falls to a reference value or below and to provide an unsolidified sampler suitable for the testing method. <P>SOLUTION: After the execution of the improvement work of improved ground, an unsolidified sampler at any depth is collected when the improved ground (g) is in an unsolidified state. Compaction test is performed on the unsolidified sample after its collection to estimate its final strength of a material age of four weeks on the basis of results of the compaction test. The unsolidified sampler includes a plurality of mold cans 3 to be filed with an unsolidified sample; a plurality of samplers 2 for each housing the mold cans 3; a long main rod 1 to which the plurality of samplers 2 are mounted longitudinally at regular intervals; and a pressing means for pressing the unsolidified sample in the mold cans 3. The pressing means includes a pneumatic cylinder 4 for vertically moving a pressing plate 6 via an operating rod 5. By vertically moving the pressing plate 6, the unsolidified sample can be filled in the mold cans 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to an improved ground test method and an unsolidified sampler. The ground improvement is performed by mixing the cement-based solidifying material liquid into the soft ground, stirring it, and making it into a ground with high compressive strength. This improved ground is called an improved body. Whether or not the improved body has the necessary compressive strength is confirmed by collecting a part of the improved body and conducting a compression test.
The present invention relates to an improved ground test method for confirming the quality of such an improved body and an unsolidified sampler used therefor.

The quality of ground improvement can be assured by the compressive strength obtained by compressing the test specimen solidified after elapse of 4 weeks (age) after construction.
In the conventional sampling method of this test body, the improved body is solidified 3 to 4 weeks after construction, and then is collected by boring. The strength of the specimen was confirmed by compressing the specimen after 4 weeks of age.

As described above, there is a conventional technique disclosed in Patent Document 1 as a technique for boring and removing a test body after the improved body is solidified.
The boring rod used in this prior art has a tooth at the tip and rotates it to dig, but such a boring machine itself is a large-scale device that cannot be used easily. is there.

In addition, the above prior art has a problem in construction. That is, in the actual site, the next work will not take 3 to 4 weeks until the boring is completed, and the work process will be extended.
In addition, if the quality of the specimen obtained by boring does not meet the standards, the foundation of the building built on the solidified improved body must be removed and the improvement work must be performed again. Don't be. In this case, a considerable amount of time and work are wasted.

JP 2003-74045 A

  In view of the above circumstances, an object of the present invention is to provide a test method for an improved ground in which the quality of an improved body can be confirmed quickly and re-construction can be easily performed when the quality of the improved body is below a reference value. Another object of the present invention is to provide an unsolidified sampler suitable for the test method.

The test method for the improved ground of the first invention is that after the improvement work of the ground improvement body is performed, an unsolidified sample of an arbitrary depth is collected when the improved body is in an unsolidified state, and a compression test is performed after the unsolidified sample is collected. The final strength at the age of 4 weeks is estimated from the result of the compression test.
The unsolidified sampler of the second invention is a sampler used in the test method of claim 1 and contains a plurality of mold cans for filling the unsolidified sample and each mold can. A plurality of samplers, a long support having the plurality of samplers attached at equal intervals in the longitudinal direction, and a pushing means for pushing an unsolidified sample into the mold can housed in the sampler. It is characterized by comprising.
An unsolidified sampler according to a third aspect of the present invention is the second aspect of the present invention, wherein the long support is a long main rod, and the pushing means is a push plate disposed above the sampler, It comprises an operating rod that moves the push plate up and down and a drive source that moves the operating rod up and down.
The unsolidified sampler according to a fourth aspect of the present invention is the second aspect, wherein the long support comprises a long outer cylinder and a long inner cylinder inserted into the outer cylinder, Openings are formed in the outer cylinder at equal intervals in the longitudinal direction, and blades are formed adjacent to the openings, and the inner cylinder is formed with openings at equal intervals in the longitudinal direction. A mold can housing portion is formed immediately below, and the push-in means extends from the upper end position of the opening of the outer cylinder into the opening of the inner cylinder, and a drive source that moves the inner cylinder up and down It is characterized by the following.

According to the first invention, the compression test is performed on the unsolidified sample when the improved body from 3 to 5 days after the construction is unsolidified, and the final strength is estimated from the test value. For this reason, if an estimated value is obtained such that the final strength of the improved ground is insufficient, it can be reconstructed immediately, so that the work process at the site is not hindered.
According to the second aspect of the invention, since the long support is a basic structure, it can be inserted into the unsolidified improved body with a light force, and a large-scale device is not obtained. Further, since the unsolidified sample is pushed into the mold can by the pushing means, it can be easily collected.
According to the third invention, when the operating rod is moved up and down by the drive source in a state where the long main rod is inserted into the unsolidified improved body, the surrounding unsolidified sample is transferred to the mold can in the sampler by the push plate. Because it is pushed in, the sample can be collected easily.
According to the fourth aspect of the present invention, when the outer cylinder is rotated around its axis in a state where the long outer cylinder is inserted into the unsolidified improved body, the unsolidified sample around the blade plate is moved from the opening to the inside of the inner cylinder. Can be pushed in. When the inner cylinder is moved upward by the drive source, the material sandwiched between the backing plates is pushed into the mold can, and thus the sample can be easily collected.

Next, an embodiment of the present invention will be described with reference to the drawings.
1A and 1B show a sampler A according to a first embodiment of the present invention, in which FIG. 1A is a state in which a push plate is closed, and FIG. 1B is an explanatory view in a state in which the push plate is opened. FIG. 2 is an enlarged view of one sampler in the same embodiment. FIG. 3 is a perspective view of a sampler and a mold can. FIG. 4 is an explanatory diagram of how to use the sampler A of the first embodiment.

  In FIG. 1, reference numeral 1 denotes a main rod, which is a bar-like long member of about 4 to 5 m. Samplers 2 are attached to the main rod 1 at equal intervals. If this mounting interval is 33.3 cm, for example, three unsolidified samples can be collected within 1 m, so that the strength of the improved body in the depth direction can be estimated with high accuracy.

An air cylinder 4 as a vertical drive source is attached to the upper end of the main rod 1, and an operation rod 5 is suspended from the rod 4 a of the air cylinder 4. The operation rod 5 is a rod-like member having a length close to that of the main rod 1. Then, push plates 6 are attached to the operation rod 5 at equal intervals. This mounting interval is 33.3 cm, similar to the sampler 2.
Then, as shown in FIG. (A), when the air cylinder 4 is extended, the operating rod 5 is lowered and the sampler 2 is covered with the push plate 6, and as shown in FIG. When contracted, the operating rod 5 rises to release the push plate 6 from the sampler 2. The push plate 6 plays a role of introducing and filling unsolidified soil into the sampler 2.

The details of the sampler 2 and the pressing plate 6 will be described with reference to FIG.
The sampler 2 is a cylindrical container having an open top surface and a bottom. A mold can 3 to be described later can be inserted into the sampler 2.
The sampler 2 is fixed to the main rod 1 with a mounting bracket 7. The push plate 6 is a lid-like member having a size that closes the upper opening of the sampler 2.
A guide pipe 8 is fixed to the base of the push plate 6, and the guide pipe 8 moves up and down along the main rod 1. Further, the guide pipe 8 is fixed to the operation rod 5 by a mounting bracket 10.

A plurality of guide fittings 11 are fixed to the operation rod 5 at equal intervals above or below the attachment fitting 10. The front end of the guide fitting 11 is bifurcated, for example, and moves up and down in contact with the outer periphery of the main rod 1 from the left and right. Therefore, when the operating rod 5 is moved up and down by the air cylinder 4, the push plate 6 repeats the up and down movement above the sampler 2, and the push plate 6 can be closed or opened. In FIG. 2, the solid line indicates a state where the push plate 6 is closed, and the alternate long and short dash line indicates a state where the push plate 6 is opened.
The air cylinder 4 and the pushing plate 6 constitute pushing means referred to in the claims.

  As shown in FIG. 3, the mold can 3 can be freely taken in and out of the sampler 2. The mold can 3 has a bottomed cylindrical shape and is a paper container slightly smaller than the sampler 2. After the mold can 3 is filled with an unsolidified sample and then cured for a required number of days and solidified, it can be subjected to a compression test or the like.

Based on FIG. 4, the usage method of the said sampler A is demonstrated.
(1) Insert the sampler A into the improvement body g in an unsolidified state.
Insertion can be performed with the weight of the sampler A or with a force similar to human power.
(2) The sampler A is attached to the bottom of the improved body g.
(3) The push plate 6 of the sampler A is raised and the upper surface of the sampler 2 is opened.
(4) The push plate 6 of the sampler A is lowered and the upper surface of the sampler 2 is closed.
When the vertical movement of the pressing plate 6 is repeated, unsolidified soil g around the pressing plate 6 is introduced into the sampler 2 and filled into the mold can 3.
(5) Pull up the sampler A. Thereafter, the mold can 3 is taken out.

When the mold can 3 filled with unsolidified soil is pulled up and cured on the ground to solidify the unsolidified soil, it becomes a test specimen.
Since the sampler A of the present embodiment has a long main rod 1 as a basic structure, it can be inserted into the unsolidified improved body g with a light force, and does not become a large-scale device. Further, since the unsolidified soil is pushed into the mold can 3 by the air cylinder 4, it can be easily collected.
Further, when the operating rod 5 is moved up and down by the air cylinder 4 with the long main rod 1 inserted into the unsolidified improved body g, the surrounding unsolidified soil g in the sampler 2 is removed by the push plate 6. Since it can be pushed into the mold can 3, the sample can be easily collected.

  When the sampler A of this embodiment is used, a specimen can be collected immediately after the improved body is constructed, and it takes 3 days at the shortest to cure the collected specimen, generally 7 days. The final compressive strength of the improved body can be estimated from the compressive strength of the body. For this reason, if an estimated value is obtained such that the final strength of the improved ground is insufficient, it can be reconstructed immediately, and the work process at the site will not be hindered.

  5A and 5B show a sampler B according to a second embodiment of the present invention, where FIG. 5A is a front view and FIG. 5B is a side view. FIG. 6 is a cross-sectional view of a drive unit in the sampler B. FIG. 7 is a cross-sectional view of a sample collection portion in the sample collector B. 8A is a view taken along the line 8a in FIG. 7, and FIG. 8B is a view taken along the line 8b in FIG.

In FIG. 5, 21 is an outer cylinder, which is a long pipe material of about 4 to 5 m. An inner cylinder 22 is inserted into the outer cylinder 21. The inner cylinder 22 is a pipe material that is slightly shorter than the outer cylinder 21.
The inner cylinder 22 is moved up and down by an air cylinder 23 attached to the upper end of the outer cylinder 21.
In addition, sampling units 30 are attached to the outer cylinder 21 and the inner cylinder 22 at equal intervals. As for this mounting interval, if the interval is 33.3 cm, three unsolidified samples can be collected within 1 m, so that the strength of the improved body in the depth direction can be estimated with high accuracy.

As shown in FIG. 6, an air cylinder 23 as a vertical drive source is attached to the upper end of the outer cylinder 21, and an inner cylinder 22 is connected to a rod 23 a of the air cylinder 23.
When the air cylinder 23 extends and contracts, the inner cylinder 22 moves up and down so that unsolidified soil can be filled as will be described later.

Next, the sampling unit 30 will be described with reference to FIGS.
The outer cylinder 21 is formed with an opening 31 large enough to insert a mold can. Specifically, the vertical dimension is larger than the mold can 3 and the opening in the circumferential direction is about 1/3.
A blade 32 is attached to the side surface of the opening 31. The vane plate 32 is a plate material having the same vertical dimension as the opening 31, and projects outward from one side edge of the opening 31. Its function is to scrape unsolidified soil, and as long as the function is fulfilled, the dimensions and the like may be arbitrarily selected.

A contact plate 33 extending from the upper end edge of the opening 31 to the inside of the outer cylinder 21 and the inner cylinder 22 is attached.
The abutting plate 33 has a semicircular shape on the inner side, and is slightly spaced from the inner periphery of the inner cylinder 22. That is, it does not interfere with the vertical movement of the inner cylinder 22, but functions as a baffle plate used for filling unsolidified soil described later.

An opening 34 is also formed in the inner cylinder 22. The opening 34 has the same vertical dimension and width dimension as the opening 31 of the outer cylinder 21.
The upper edge of the opening 34 of the inner cylinder 22 is not joined to the abutting plate 33 and can be separated.

  A plurality of bolts 35 are planted on the side wall of the inner cylinder 22 below the opening 34 of the inner cylinder 22. The bolt 35 is an inward mold can receiving portion 36 that extends inward and supports the bottom of the mold can 3.

When the mold can 3 is placed in the mold can housing portion 36 and the inner cylinder 22 is pulled up by the air cylinder 23, the distance between the mold can 3 and the abutting plate 33 can be reduced.
In the present embodiment, the air cylinder 23 and the contact plate 33 constitute a pushing means.

Based on FIGS. 9-11, the usage method of the said sampler B is demonstrated.
Although not shown in the figure, first, the sampler B is inserted into an improved body in an unsolidified state. Insertion can be performed with the weight of the sampler B or with a force similar to human power.
FIG. 9 is an explanatory view showing a state in which the sampler B is inserted into the improved body. In this state, the unsolidified soil g exists in the form of mud around the sampler B. Although unsolidified soil g is clinging around the slats 32, it has not yet entered through the openings 31 and 34.

FIG. 10 is an explanatory diagram of the state rotated by the sampler B. As shown in FIG. 10, the sampler B is rotated around the axis. Then, the unsolidified soil g is pushed by the blade 32 and pushed into the inner cylinder 22 from the openings 31 and 34.
FIG. 11 is an explanatory diagram of a state in which the inner cylinder is raised by the sampler B. As shown in FIG. 11, when the inner cylinder 22 is pulled up, the mold can 3 is also lifted, so that the unsolidified soil g is sandwiched between the backing plates 33 and filled into the mold can 3. When the mold can 3 is thus filled with the unsolidified soil g, the sampler B is pulled up. Thereafter, the mold can 3 is taken out and used for the test.

When the mold can 3 filled with the unsolidified soil g is pulled up and cured on the ground to solidify the unsolidified soil g, it becomes a test specimen.
Since the sampler B of the present embodiment has a long outer cylinder 21 and an inner cylinder 22 as a basic structure, it can be inserted into the improved body g in an unsolidified state with a light force. It does not become a device.
Further, in a state where the long outer cylinder 21 is inserted into the unsolidified improved body g, the rotation of the outer cylinder 21 around the axis and the upward movement of the inner cylinder 22 by the air cylinder 23 cause the unsolidified soil g to be molded. Since it can be pushed into the interior of 3, the sample can be collected easily.

  Even when using the sampler B of the present embodiment, the specimen can be collected immediately after the improved body is constructed, and it takes at least three days for the specimen to be cured, generally seven days. The final compressive strength of the improved body can be estimated from the compressive strength of the test body. For this reason, if an estimated value is obtained such that the final strength of the improved ground is insufficient, it can be reconstructed immediately, and the work process at the site will not be hindered.

1 shows a sampler A according to a first embodiment of the present invention, in which (A) is a state in which a push plate is closed, and (B) is an explanatory view in a state in which the push plate is opened. It is an enlarged view of one sampler in a 1st embodiment of the present invention. It is a perspective view of a sampler and a mold can. It is explanatory drawing of the usage method of the sampler A of 1st Embodiment. The sampler B of 2nd Embodiment of this invention is shown, (A) A figure is a front view, (B) A figure is a side view. It is sectional drawing of the drive part in the sampler B of 2nd Embodiment. It is sectional drawing of the sample collection part in the sample collector B of 2nd Embodiment. FIG. 8A is a view taken along the arrow 8a in FIG. 7, and FIG. B is a view taken along the arrow 8b in FIG. It is explanatory drawing of the state which inserted the sampler B in the improved body. It is explanatory drawing of the state rotated with the sample collector B. FIG. It is explanatory drawing of the state which raised the inner cylinder with the sampler.

Explanation of symbols

1 Main Rod 2 Sampler 3 Mold Can 4 Air Cylinder 5 Operation Rod 6 Push Plate 21 Outer Cylinder 22 Inner Cylinder 23 Air Cylinder 32 Blade Plate 33 Catch Plate

Claims (4)

After the improvement work of the ground improvement body, when the improvement body is in an unsolidified state, an unsolidified sample of an arbitrary depth is collected,
Compression test after taking the unsolidified sample,
A method for testing an improved ground, wherein a final strength at a material age of 4 weeks is estimated from a result of the compression test. A sampler used in the test method of claim 1,
A plurality of mold cans for filling the unsolidified sample;
A plurality of samplers for accommodating the mold cans one by one;
A long support attached with a plurality of samplers at equal intervals in the longitudinal direction;
An unsolidified sampler comprising: pushing means for pushing an unsolidified sample into the mold can accommodated in the sampler. The long support is a long main rod;
3. The pushing means comprises a push plate disposed above the sampler, an operation rod that moves the push plate up and down, and a drive source that moves the operation rod up and down. Unsolidified sampler. The long support body is composed of a long outer cylinder and a long inner cylinder inserted into the outer cylinder,
In the outer cylinder, openings are formed at equal intervals in the longitudinal direction, and blades are formed adjacent to the openings,
In the inner cylinder, openings are formed at equal intervals in the longitudinal direction, and a mold can accommodating portion is formed immediately below the opening,
The said pushing means consists of the contact plate extended in the said opening of the said inner cylinder from the upper end position of the said opening of the said outer cylinder, and the drive source which moves the said inner cylinder up and down. Unsolidified sampler.

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