JP4378241B2 - Vertical loading test method for existing piles - Google Patents

Description

  This invention is a vertical loading test method for existing piles to confirm whether the existing pile used in the existing building can be reused as a pile in a new building, and to check the support performance of the pile. Hereinafter, it may be simply referred to as a loading test method.), And more specifically, relates to a method for performing a loading test by obtaining a reaction force on an existing building.

  When rebuilding a building, the existing pile used in the existing building is reused as a pile in a new building to shorten the construction period and reduce costs. At this time, a loading test is carried out on the existing pile, the supporting performance of the existing pile is confirmed, and the existing pile with utility value is reused. Technology has been developed to obtain a reaction force on the building and perform a loading test.

For example, in the loading test method of Patent Document 1, the head of an existing pile to be tested in an existing building is cut at a predetermined height to cut the foundation slab and the edge, and the foundation slab and the existing pile that have been cut are cut off. A jack is installed between them, and a loading test is carried out by obtaining a reaction force on the foundation slab.
Japanese Patent Laid-Open No. 11-264247

  Since the loading test method of Patent Document 1 obtains a reaction force on the foundation slab of an existing building and performs a loading test, a large test load cannot be applied to the existing pile.

  Further, in order to secure a space for installing the jack between the existing pile and the foundation slab, the ground below the foundation slab is excavated, but it is necessary to construct a retaining wall around the work space. In addition, it is difficult to carry out excavated soil generated during excavation and a test device such as a jack used for a loading test into an underground work space, which has problems such as poor workability and high cost.

  Moreover, if the groundwater level is high, the test apparatus is immersed in the groundwater, which makes it difficult to implement.

  The purpose of the present invention is to construct a strong concrete reaction body in an existing building located above the existing pile, obtain a reaction force from the concrete reaction body, and load test the existing pile with the foundation frame cut off. It is to provide a vertical loading test method for an existing pile that can apply reaction force to the existing building and apply a large test load to the existing pile.

  The purpose of the present invention is to provide a vertical loading test method for existing piles that can perform a loading test above the foundation frame of an existing building, has good workability, contributes to cost reduction, and is not affected by the groundwater level. Is to provide.

As a means for solving the problems of the prior art, a vertical loading test method for an existing pile according to the invention described in claim 1 is:
A vertical loading test method for reusing existing piles used in an existing building when rebuilding a building,
Cutting the edge between the existing pile to be tested and the foundation frame of the existing building;
Above the existing pile, a step of constructing a concrete reaction body with a configuration capable of obtaining a reaction force of a test load from an existing building;
Installing a jack at the upper end of the existing pile, connecting the jack and the concrete reaction body, measuring the support performance by applying a test load to the existing pile with the jack;
It is characterized by comprising.

The invention according to claim 2 is the vertical loading test method for existing piles according to claim 1,
The foundation skeleton directly above the existing pile to be tested is cut into substantially the same shape as the planar shape of the existing pile, and the edges of the existing pile and the foundation skeleton are cut.

The invention according to claim 3 is the vertical loading test method for existing piles according to claim 1,
The concrete reaction body is constructed as reinforced concrete, steel reinforced concrete, or steel concrete.

Invention of Claim 4 is the vertical load test method of the existing pile described in Claim 1 or 3,
The concrete reaction body in the loading test of the existing pile located below the beam between the columns of the existing building and the beam frame is the reaction body connecting the columns of the column and the beam frame above the existing pile. The force wall is constructed so as to be continuous in a single layer or multiple layers in the vertical direction, and the reaction force of the test load is obtained from an existing building.

Invention of Claim 5 is the vertical loading test method of the existing pile described in Claim 1 or 3,
The concrete reaction force body in the case of loading test the existing pile located below the beam between the columns of the existing building and the beam frame is a reaction force column or reaction beam that hangs down from the beam above the existing pile. In addition, the reaction force column or reaction beam is integrated with the reaction force column or the reaction force beam, and the reaction force wall connecting the columns of the column / beam frame is constructed so as to be continuous in a single layer or multiple layers in the vertical direction. The reaction force of the load is obtained from the existing building.

Invention of Claim 6 is the vertical load test method of the existing pile described in Claim 1 or 3,
The pillars and beam frames are arranged in a rectangular shape, trapezoidal shape, or flat shape when viewed in plan, and the concrete reaction body when loading test an existing pile that is displaced from the position below the pillar at the four corners is A central reaction wall having a length substantially equal to the length between columns of the frame is constructed along the beam above the existing pile, and further, an outer reaction connecting the columns at the four corners on both sides of the central reaction wall. Each of the force walls is constructed, and the central reaction wall and the outer reaction wall are integrated to form a reaction wall unit. The reaction wall unit is constructed so as to be continuous in a single layer or multiple layers in the vertical direction. The reaction force of the test load is obtained from an existing building.

The invention according to claim 7 is the vertical loading test method for existing piles according to claim 1 or 3,
The pillars and beam frames are arranged in a rectangular shape, trapezoidal shape, or flat shape when viewed in plan, and the concrete reaction body when loading test an existing pile that is displaced from the position below the pillar at the four corners is The reaction force walls that connect the four corners in the diagonal direction are constructed above the existing piles, and these are integrated into a reaction wall unit. The reaction wall unit is a single layer or multiple layers continuous. The reaction force of the test load is obtained from the existing building.

Invention of Claim 8 is the vertical load test method of the existing pile described in Claim 1 or 3,
The pillars and beam frames are arranged in a rectangular shape, trapezoidal shape, or flat shape when viewed in plan, and the concrete reaction body when loading test an existing pile that is displaced from the position below the pillar at the four corners is The reaction force slab is constructed in the area surrounded by the four pillars at the four corners on the lower floor or upper surface of the upper floor directly above the existing pile or on both surfaces, and the reaction force of the test load is obtained from the existing building. It is characterized by that.

Invention of Claim 9 is the vertical load test method of the existing pile described in any one of Claims 4-8,
The reaction wall or reaction wall unit or reaction column is constructed so as to be continuous in a single layer or multiple layers in the vertical direction from the existing building to a height at which a reaction force of a predetermined test load can be taken. To do.

Invention of Claim 10 is the vertical loading test method of the existing pile described in any one of Claim 1 or Claims 3-8,
It is characterized by constructing a reaction wall on the surrounding frame and making it a part of the concrete reaction body.

Invention of Claim 11 is the vertical load test method of the existing pile described in any one of Claim 1 or Claims 3-8,
It is characterized by building braces on the surrounding frame and reinforcing concrete reaction bodies.

Invention of Claim 12 is the vertical load test method of the existing pile described in any one of Claim 1, Claim 3-8, or Claim 10, 11,
The concrete reaction body is used as the main frame of the new building.

  The vertical loading test method for an existing pile according to the present invention is to construct a strong concrete reaction body in an existing building located above the existing pile, obtain a reaction force on the concrete reaction body, and connect the edge to the foundation frame. Since the loading test is carried out on the cut existing pile, a large test load can be applied to the existing pile by obtaining a reaction force on the existing building.

  Since the loading test can be performed above the foundation frame of the existing building, there is no need to excavate the ground, and construction of a retaining wall and other incidental work can be omitted. In addition, excavated soil does not need to be generated and carried out, and it is easy to carry in and out a testing device such as a jack used for the loading test, so that the workability is good and the cost can be reduced. Moreover, it is not affected by the groundwater level.

  Cut the edge between the existing pile to be tested and the foundation frame of the existing building. A concrete reaction force body is constructed above the existing pile with a configuration capable of obtaining the reaction force of the test load from the existing building. A jack is installed at the upper end of the existing pile, the jack is connected to the concrete reaction body, and a test load is applied to the existing pile with the jack to measure the support performance.

  The Example of the vertical loading test method of the existing pile which concerns on the invention described in Claims 1-4, Claim 9, and Claim 12 is demonstrated based on FIGS. The loading test method of the present invention is carried out in order to confirm whether the existing pile 2 used in the existing building 1 can be reused and the supporting performance of the existing pile 2 when rebuilding the building.

  First, among a plurality of existing piles 2 of the existing building 1, it is located below the beam 5 between the left and right columns 4 and 4 of a column / beam frame (hereinafter simply referred to as a frame) 3 a. The existing pile to be tested (hereinafter abbreviated as “test pile”) 2a is selected (see FIG. 4). Then, as shown in FIG. 1, the test body 2 a and the base body 6 are punched through the base body 6 directly above the test pile 2 a by means of coring or the like from the upper side so as to be substantially the same as the planar shape of the test pile 2 a. (Invention of claim 2).

  Next, as shown in FIG. 2, a concrete reaction force body 7 is constructed in a configuration capable of obtaining a test load reaction force from the existing building 1 above the test pile 2 a. Specifically, in order to express a reaction force of a predetermined size in the plane of the frames 3a, 3b, ... of a plurality of layers (but may be a single layer) located above the test pile 2a, The reinforced concrete reaction wall 8 is constructed so as to be continuous in the vertical direction (invention of claim 9). In the present embodiment, the reaction wall 8 connecting the left and right columns 4 and 4 of the frame 3a is connected to the lower frame 3a with the beam 5 directly above the test pile 2a interposed therebetween, and the upper end of the test pile 2a later. It is constructed by hanging down from the beam 5 leaving a space (height) in which the jack 9 can be installed in the part. Furthermore, a reaction force wall 8 that connects the left and right columns 4 and 4 of the upper frame 3b is also built up from the beam 5 in the upper frame 3b. As a result, the pillar 4, the beam 5, and the reaction wall 8 of the existing building 1 are integrated into a concrete reaction body 7, and a large test load is applied to the test pile 2 a by obtaining the reaction force in the existing building 1. It becomes the structure which can be done (Invention of Claim 3 and 4). And although concrete illustration is abbreviate | omitted, the said concrete reaction force body 7 can be formed by arrange | positioning a reinforcing bar in the surface of frame 3a, 3b, assembling a formwork, and only placing concrete, There is no need to carry in and assemble a specially large member (for example, a reaction force girder), and the workability is good. Further, when the concrete reaction body 7 is constructed, the application range is wide because there is almost no space restriction due to fixtures or equipment of existing buildings.

  Finally, as shown in FIG. 3, a jack 9 is installed at the upper end of the test pile 2 a (that is, the upper end of the foundation frame 6 that is rigidly connected to the test pile 2 a). And the lower end of the lower reaction force wall 8 constituting the concrete reaction force body 7 are connected, and a test load is applied by the jack 9 to measure the support performance. Since the loading test can be carried out above the foundation frame 6 of the existing building 1, it is not necessary to excavate the ground, and construction of a retaining wall and other accompanying work can be omitted at all. In addition, excavated soil does not need to be generated and carried out, and it is easy to carry in and out a testing device such as a jack used for the loading test, so that the workability is good and the cost can be reduced. Moreover, it is hardly affected by the groundwater level.

  After that, the existing building 1 is dismantled and the existing pile 2 that has been subjected to the loading test and confirmed the supporting performance as described above is reused as a pile of a new building. At this time, the concrete reaction body 7 is dismantled. However, it is economical to use it as a main structure of a new building (invention of claim 12).

  In the first embodiment, the concrete reaction force body 7 is constructed using the frame 3a (3b) of the existing building 1, but the concrete reaction force is utilized using the pit portion 6a of the foundation frame 6 as shown in FIG. The force body 7 may be constructed. In this case, first, the edge between the upper end portion of the test pile 2a and the footing 6b is cut. And the reaction force wall 8 is constructed | assembled to the height which can obtain the reaction force of a predetermined | prescribed test load so that it may continue upwards from the pit part 6a of the foundation housing 6. FIG. Finally, the jack 9 is installed in the upper end part of the test pile 2a, the jack 9 and the lower reaction force wall 8 are connected, a test load is applied to the test pile 2a with the jack 9, and a support performance is measured.

  In the first and second embodiments, the existing pile 2 that is relatively near the column 4 is selected as the test pile 2a as shown in the figure, but as shown in FIGS. 6 and 7, the left and right columns of the frame 3a are selected. Even if the existing pile 2 located in the approximate center between 4 and 4 is selected as the test pile 2a, it can be implemented in substantially the same manner. In addition, the Example shown in FIG. 6 comprises the concrete reaction force body 7 using the pit part 6a of the foundation frame 6 similarly to FIG.

Although the said Example 1-Example 3 comprises the lower end part of the concrete reaction force body 7 with the reaction force wall 8, as shown in FIG.8 and FIG.9, it hangs down from the beam 5 just above the test pile 2a. A reinforced concrete reaction force column 10 (not shown but may be a reaction force beam) may be constructed to constitute the lower end portion of the concrete reaction force body 7 (the invention according to claim 5).
In this embodiment, only the lower end portion of the concrete reaction force body 7 is constituted by the reaction force column 10 or the reaction force beam, but the reaction force column 10 or the reaction force is continuous in a single layer or a plurality of layers in the vertical direction. A beam (resulting in a reaction wall) may be constructed (the invention according to claim 9).

  Although the said Example 1- Example 4 has selected the existing pile 2 located under the beam 5 as the test pile 2a between the left and right pillars 4 and 4 of the frame 3a of the existing building 1, this limit Not. When the frame 3a (3b) is arranged in a rectangular shape, a trapezoidal shape, or a flat shape when viewed in plan, the existing pile 2 that is shifted from the position below the pillar 4 at the four corners is selected as the test pile 2a. Also good. Incidentally, in this embodiment, as shown in FIGS. 10 and 11, the frame 3a (3b) is arranged in a rectangular shape when seen in a plan view, and a diagonal line A connecting the four columns 4 at the four corners. The existing pile 2 located below the intersection C between B and B is selected as the test pile 2a.

  In this case, the concrete reaction body 7 has a central reaction wall 11 made of reinforced concrete having a length substantially equal to the length between the left and right columns 4 and 4 of the frame 3a (3b) above the test pile 2a. (In the same plane as the beam 5). Further, on the both sides of the central reaction force wall 11, outer reaction force walls 12, 12 connecting the pillars 4 and 4 at the four corners are constructed, respectively, and the central reaction force wall 11 and the outer reaction force walls 12, 12 are connected. The reaction wall unit 13 is integrated. The reaction wall unit 13 is constructed so as to be continuous in a single layer or a plurality of layers in the vertical direction, and the reaction force of the test load is obtained from the existing building 1 (the invention according to claim 6 or claim 9).

In addition, when the frame 3a (3b) is arranged in a rectangular shape, a trapezoidal shape, or a flat shape as viewed in a plan view, a test pile 2a that is displaced from a position below the pillar 4 at the four corners is loaded. As shown in FIG. 12, the concrete reaction force body 7 is constructed with a reinforced concrete reaction force wall 14 connecting the columns 4 and 4 adjacent to each other in the diagonal A direction above the test pile 2a, and further in the diagonal B direction. The reaction wall 15 made of reinforced concrete connecting the columns 4 and 4 adjacent to each other is constructed, and these are integrated into a reaction wall unit 16. The reaction wall unit 16 may be constructed so as to be continuous in a single layer or a plurality of layers in the vertical direction, and the reaction force of the test load may be obtained from the existing building 1 (invention according to claim 7 or claim 9). .
Incidentally, also in this embodiment, the frame 3a (3b) is arranged in a rectangular shape when seen in a plan view, and is existing below the intersection C of the diagonal lines A and B connecting the four pillars 4 at the four corners. The pile 2 is selected as the test pile 2a.

Furthermore, when the frame 3a (3b) is arranged in a rectangular shape, a trapezoidal shape, or a flat shape as viewed in a plane, and the loading test is performed on the test pile 2a that is shifted from the position below the pillar 4 at the four corners. As shown in FIGS. 13 and 14, the concrete reaction body 7 has a lower reaction force in a region surrounded by the four pillars 4 at the four corners on the lower surface of the upper floor 17 directly above the test pile 2a. Build the slab 18. Further, the upper reaction floor slab 19 may be constructed in the area surrounded by the four pillars 4 at the four corners on the upper floor 17 to obtain the reaction force of the test load from the existing building 1. (Invention of Claim 8).
In consideration of the magnitude of the test load, the reaction force may be obtained by constructing only the lower reaction force slab 18 or the upper reaction force slab 19, or a single layer or a plurality of layers are continuous in the vertical direction. Thus, a reaction force slab (resulting in a block-shaped reaction force wall) may be constructed (the invention according to claim 9).

  The concrete reaction force bodies 7 of the first to seventh embodiments are constructed by constructing reaction force walls 8 and the like on the frames 3a and 3b arranged in the vertical direction, but as shown in FIG. 15, the frames 3a arranged in the vertical direction. In addition to 3b, the reaction wall 20 may be constructed and constructed on the surrounding frames 3a and 3b (invention of claim 10). Incidentally, as shown in FIG. 16, if the base slab 6 c of the base frame 6 is removed and removed, the height of the reaction force wall 8 can be gained and a large reaction force can be secured. In some cases, the force walls 8 and 20 can be omitted.

  Moreover, as shown in FIG.17 and FIG.18, it is good also as a structure which constructed | assembled the brace 21 in the surrounding frame 3b (it is also possible for 3a), and reinforced the concrete reaction force body 7 (invention of Claim 11).

  Although the concrete reaction body 7 of the said Example 1- Example 8 is made into reinforced concrete structure, it is good also as steel-framed reinforced concrete structure or steel-framed concrete structure (invention of Claim 3).

  In addition, although the Example of this invention was described above, this invention is not limited to such an Example at all, In the range which does not deviate from the summary of this invention, it can implement with a various form.

It is the elevation which showed the procedure of the vertical loading test method of the existing pile of Example 1 notionally. It is the elevation which showed the procedure of the vertical loading test method of the existing pile of Example 1 notionally. It is the elevation which showed the procedure of the vertical loading test method of the existing pile of Example 1 notionally. It is AA arrow sectional drawing of FIG. It is the elevation which showed notionally the state just before implementing a loading test with the vertical loading test method of the existing pile of Example 2. FIG. It is the elevation which showed notionally the state just before implementing a loading test with the vertical loading test method of the existing pile of Example 3. FIG. It is BB arrow sectional drawing of FIG. It is the elevation which showed notionally the state just before implementing a loading test with the vertical loading test method of the existing pile of Example 4. FIG. It is CC sectional view taken on the line of FIG. It is the elevation which showed notionally the state just before implementing a loading test with the vertical loading test method of the existing pile of Example 5. FIG. It is DD sectional view taken on the line of FIG. It is the cross-sectional view which showed the shape of the concrete reaction body in the vertical loading test method of the existing pile of Example 6. FIG. It is the elevation which showed notionally the state just before implementing a loading test with the vertical loading test method of the existing pile of Example 7. FIG. It is EE arrow sectional drawing of FIG. It is the elevation which showed notionally the state just before implementing a loading test with the vertical loading test method of the existing pile of Example 8. FIG. It is the elevation which showed the different form of FIG. FIG. 16 is an elevational view showing a further different form of FIG. 15. FIG. 16 is an elevational view showing a further different form of FIG. 15.

Explanation of symbols

1 Existing building 2 Existing pile 2a Existing pile to be tested (test pile)
3a, 3b Frame 4 Column 5 Beam 6 Foundation frame 7 Concrete reaction body 8 Reaction wall 9 Jack 10 Reaction column 11 Central reaction wall 12 Outer reaction wall 13 Reaction wall unit 14, 15 Reaction wall 16 Reaction force Wall unit 17 Upper floor 18 Lower reaction slab 19 Upper reaction slab 20 Reaction wall 21 Brace

Claims (12)

A vertical loading test method for reusing existing piles used in an existing building when rebuilding a building,
Cutting the edge between the existing pile to be tested and the foundation frame of the existing building;
Above the existing pile, a step of constructing a concrete reaction body with a configuration capable of obtaining a reaction force of a test load from an existing building;
Installing a jack at the upper end of the existing pile, connecting the jack and the concrete reaction body, measuring the support performance by applying a test load to the existing pile with the jack;
A vertical loading test method for existing piles, comprising:   The existing pile according to claim 1, wherein the foundation pile just above the existing pile to be tested is cut into substantially the same shape as the planar shape of the existing pile, and the edge of the existing pile and the foundation pile is cut. Vertical loading test method.   The method for vertical loading test of an existing pile according to claim 1, wherein the concrete reaction body is constructed as a reinforced concrete structure, a steel reinforced concrete structure or a steel concrete structure.   The concrete reaction body in the loading test of the existing pile located below the beam between the columns of the existing building and the beam frame is the reaction member connecting the columns of the column and the beam frame above the existing pile. The vertical loading test method for an existing pile according to claim 1 or 3, wherein the force wall is constructed so as to be continuous in a single layer or a plurality of layers in the vertical direction, and the reaction force of the test load is obtained from the existing building. .   The concrete reaction force body in the case of loading test of the existing pile located below the beam between the columns of the existing building and the beam frame is a reaction force column or reaction beam hanging from the beam above the existing pile. In addition, the reaction force column or reaction beam is integrated with the reaction force column or the reaction force beam, and the reaction force wall connecting the columns of the column / beam frame is constructed so as to be continuous in a single layer or multiple layers in the vertical direction. The vertical loading test method for an existing pile according to claim 1 or 3, wherein a reaction force of the load is obtained from an existing building.   The pillars and beam frames are arranged in a rectangular shape, trapezoidal shape, or flat shape when viewed in plan, and the concrete reaction body when loading test an existing pile that is shifted from the position below the pillar at the four corners is A central reaction wall having a length substantially equal to the length between columns of the frame is constructed along the beam above the existing pile, and further, an outer reaction connecting the columns at the four corners on both sides of the central reaction wall. Each of the force walls is constructed, and the central reaction wall and the outer reaction wall are integrated to form a reaction wall unit. The reaction wall unit is constructed so as to be continuous in a single layer or multiple layers in the vertical direction. The method for vertical loading test of an existing pile according to claim 1, wherein a reaction force of a test load is obtained from an existing building.   The pillars and beam frames are arranged in a rectangular shape, trapezoidal shape, or flat shape when viewed in plan, and the concrete reaction body when loading test an existing pile that is shifted from the position below the pillar at the four corners is The reaction force walls that connect the four corners in the diagonal direction are constructed above the existing piles, and these are integrated into a reaction wall unit. The reaction wall unit is a single layer or multiple layers continuous. 4. The vertical loading test method for an existing pile according to claim 1 or 3, wherein the reaction force of the test load is obtained from an existing building.   The pillars and beam frames are arranged in a rectangular shape, trapezoidal shape, or flat shape when viewed in plan, and the concrete reaction body when loading test an existing pile that is shifted from the position below the pillar at the four corners is The reaction force slab is constructed in the region surrounded by the four pillars at the four corners on the lower floor or the upper surface of the upper floor or both surfaces directly above the existing pile, and the reaction force of the test load is obtained from the existing building. The vertical loading test method of the existing pile described in claim 1 or 3,   The reaction wall or reaction wall unit or reaction column is constructed so as to be continuous in a single layer or multiple layers in the vertical direction from the existing building to a height at which a reaction force of a predetermined test load can be taken. The vertical loading test method of the existing pile described in any one of Claims 4-8.   The vertical loading test method for an existing pile according to any one of claims 1 or 3 to 8, wherein a reaction wall is constructed in a surrounding frame and is used as a part of a concrete reaction body. .   The vertical loading test method for an existing pile according to any one of claims 1 and 3 to 8, wherein a brace is constructed on a surrounding frame and a concrete reaction body is reinforced.   The method for vertical loading test of an existing pile according to any one of claims 1 to 3, or claims 10 and 11, wherein the concrete reaction body is used as a main frame of a new building.

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