JP7051208B2 - Exposed column base structure and its manufacturing method - Google Patents

Description

The present invention relates to an exposed column base structure that supports a building and a method for manufacturing the same.

The column base structure that supports the building includes a column type and a column material. The pillar type is mainly made of concrete, and multiple reinforcing bars are buried inside it. In the exposed column base structure, the anchor bolt is embedded in the foundation concrete at the lower part and protrudes from the upper surface of the foundation concrete at the upper part. The pillar material is erected above the pillar shape by being fixed to the anchor bolts via the base plate.

Patent Document 1 describes an exposed column base structure in which grout is filled between an inner surface of a through hole formed in a base plate and an anchor bolt inserted through the through hole. In this configuration, it is said that the movement of the base plate with respect to the foundation concrete can be suppressed by restraining all the surfaces of the filled grout.

Japanese Unexamined Patent Publication No. 2008-13912

In the exposed column base structure described in Patent Document 1, when a building is vibrated due to an earthquake or the like, a horizontal external force acts from the base plate to the anchor bolts via the grout filled in the through hole to form a foundation. Stress is generated in the concrete. If this stress is excessive, the anchor bolts will be significantly deformed, the concrete around the anchor bolts will be extruded, and one side of the foundation concrete may crack. At this time, the concrete fracture surface around the anchor bolt often has a substantially conical shape, and such fracture of the foundation concrete is also referred to as “conical fracture”. Conical fractures are particularly likely to occur forward in the direction of external force, around anchor bolts that have few areas to resist concrete extrusion.

Although the exposed column base structure described in Patent Document 1 suppresses the movement of the base plate by the grout filled in the through hole, further improvement in suppressing the cone-shaped fracture due to an excessive external force has been required.

The present invention has been made in view of such problems, and provides an exposed column base structure and a method for manufacturing the same, which can suppress the movement of the base plate and the cone-shaped fracture of the foundation concrete at the same time. With the goal.

In order to solve the above problems, the exposed column base structure according to the present invention includes foundation concrete, inner anchor bolts, and outer anchor bolts provided outside the building than the inner anchor bolts. Inner anchor bolts and outer anchor bolts are pillar-shaped, vertically extending pillars, with the lower part embedded in the foundation concrete and the upper part protruding from the upper surface of the foundation concrete, and fixed to the lower end of the pillars, with the upper surface. It is a base plate in which an inner through hole and an outer through hole are formed to penetrate between the lower surface and the lower surface. , A base plate fixed to the top of the inner and outer anchor bolts, and a grout provided in the space between the upper surface of the foundation concrete and the lower surface of the base plate. Inner anchor bolts are fixed to the base plate. A gap is formed between the inner surface of the outer through hole and the outer anchor bolt so that no grout is provided.

According to this configuration, when a building is vibrated due to an earthquake or the like, an external force acts from the pillar material to the inner anchor bolt via the base plate. Since the base plate receives the reaction force from the inner anchor bolt, the movement of the base plate is suppressed.

On the other hand, a gap without grout is formed between the inner side surface of the outer through hole and the outer anchor bolt. Therefore, the action of the external force on the outer anchor bolt is suppressed until the base plate moves by a predetermined amount and the inner side surface of the outer through hole comes into contact with the outer anchor bolt. As a result, the cone-shaped fracture of the foundation concrete can be suppressed.

A grout may be provided between the inner surface of the inner through hole and the inner anchor bolt.

According to this configuration, when the grout is provided in the space between the upper surface of the foundation concrete and the lower surface of the base plate, the grout can flow in between the inner side surface of the inner through hole and the inner anchor bolt. That is, it is possible to arrange the grout in the space between the upper surface of the foundation concrete and the lower surface of the base plate and fix the inner anchor bolt to the base plate in the same process.

An inflow control member that regulates the inflow of unsolidified grout into the outer through hole may be arranged around the outer through hole.

According to this configuration, when injecting unsolidified grout into the space between the upper surface of the foundation concrete and the lower surface of the base plate, the inflow of grout between the inner surface of the outer through hole and the outer anchor bolt flows in. It can be regulated by a regulating member. As a result, it becomes possible to surely form the void.

The inflow control member has a shielding plate arranged below the base plate, and the shielding plate may shield the outer through hole.

According to this configuration, the inflow of grout between the inner surface of the outer through hole and the outer anchor bolt can be regulated by the shielding plate. As a result, the void can be surely formed.

The inflow control member may have a pressure contact member that presses the shielding plate against the lower surface of the base plate.

According to this configuration, the outer through hole can be reliably shielded by the shielding plate, and the inflow of grout between the inner side surface of the outer through hole and the outer anchor bolt can be restricted. As a result, the void can be surely formed.

The shielding plate may have a shielding plate through hole through which an outer anchor bolt is inserted, and may have a ventilation portion inside the shielding plate through hole that restricts the passage of grout while allowing the passage of air.

According to this configuration, when injecting unsolidified grout into the space between the upper surface of the foundation concrete and the lower surface of the base plate, air can be discharged from the space through the ventilation portion. As a result, voids can be formed without hindering the filling of the grout into the space.

The inflow control member is flexible and may be arranged in the void.

According to this configuration, the inflow of grout between the inner side surface of the outer through hole and the outer anchor bolt can be reliably regulated by the inflow regulating member arranged therein. The inflow control member is preferably breathable in addition to being flexible. Thereby, when the unsolidified grout is injected into the space between the upper surface of the foundation concrete and the lower surface of the base plate, air can be discharged from the space through the inflow control member. As a result, voids can be formed without hindering the filling of the grout into the space.

Further, when the base plate moves, the inflow restricting member bends, so that the action of the external force on the outer anchor bolt is suppressed. As a result, the cone-shaped fracture of the foundation concrete can be suppressed.

The inflow control member has a washer placed on the upper surface of the base plate, and the washer has a washer through hole through which an outer anchor bolt is inserted and a ventilation control portion that shields the periphery of the outer through hole to regulate ventilation. It may be formed.

According to this configuration, air stays in the space formed between the washer and the upper surface of the base plate. The retention of air above the outer through hole regulates the discharge of air through the outer through hole. With proper regulation, when injecting unsolidified grout into the space between the upper surface of the foundation concrete and the lower surface of the base plate, between the inner surface of the outer through hole and the outer anchor bolt. The inflow of grout can be regulated. As a result, it becomes possible to surely form the void.

In order to solve the above problems, the method for manufacturing an exposed column base structure according to the present invention includes foundation concrete, inner anchor bolts, and outer anchor bolts provided outside the building than the inner anchor bolts. The inner and outer anchor bolts have a spacer placement process in which spacers are placed on the upper surface of the pillar shape, with the lower part embedded in the foundation concrete and the upper part protruding from the upper surface of the foundation concrete, and a base plate at the lower end. The fixed pillar material is placed above the pillar shape, and the upper part of the inner anchor bolt is inserted into the inner through hole formed in the base plate, and the upper part of the outer anchor bolt is inserted into the outer through hole formed in the base plate. , The erection process of bringing the lower surface of the base plate into contact with the upper surface of the spacer, the fixing process of fixing the base plate by fastening the bolts to the upper part of the inner anchor bolt and the outer anchor bolt, and the upper surface of the foundation concrete. It comprises a filling step of filling the space between the bottom surface of the base plate with uncured ground. Prior to the filling step, there is a regulating member arranging step of arranging an inflow regulating member for regulating the inflow of unsolidified grout into the outer through hole around the outer through hole.

According to this manufacturing method, in the filling process, when uncured grout is injected into the space between the upper surface of the foundation concrete and the lower surface of the base plate and filled, the inner side surface of the outer through hole and the outer anchor bolt are used. The inflow of grout into the space can be regulated by the inflow control member. As a result, it becomes possible to surely form a gap between the inner side surface of the outer through hole and the outer anchor bolt.

According to the present invention, it is possible to provide an exposed column base structure and a method for manufacturing the same, which can both suppress the movement of the base plate and suppress the cone-shaped fracture of the foundation concrete.

It is a perspective view which shows the exposed type column base structure which concerns on embodiment. It is a side view which shows the exposed type column base structure of FIG. It is sectional drawing which shows the section III-III of FIG. It is sectional drawing which shows the IV-IV cross section of FIG. It is a perspective view which shows the washer of FIG. 2 is a plan view and a cross-sectional view showing an inflow control member of FIG. 2. It is explanatory drawing which shows the manufacturing process of the exposed type column base structure of FIG. It is explanatory drawing which shows the manufacturing process of the exposed type column base structure of FIG. It is a side view which shows the exposed type column base structure of FIG. It is a perspective view which shows the inflow control member which concerns on other embodiment. It is a side view which shows the exposed type column base structure provided with the inflow control member which concerns on other embodiment. It is a perspective view which shows the inflow control member which concerns on other embodiment. It is a side view which shows the exposed type column base structure provided with the inflow control member of FIG.

Hereinafter, embodiments will be described with reference to the accompanying drawings. In order to facilitate understanding of the description, the same components are designated by the same reference numerals as possible in the drawings, and duplicate description is omitted.

First, the outline of the exposed type column base structure 1 (hereinafter, also referred to as “column base structure 1”) according to the embodiment will be described with reference to FIG. 1. FIG. 1 is a perspective view showing a column base structure 1, and shows a portion corresponding to the vicinity of the outer wall of the building among a plurality of column base structures 1 provided in the building. In other words, the pillar material 31 described later corresponds to a pillar called a “corner pillar” or a “side pillar”.

The pillar base structure 1 is a structure provided at the lower part of a building and used to support the building, and can be applied to various buildings such as detached houses, apartment houses, and commercial buildings. The column base structure 1 includes a column type 2, a column member 31, and a base plate 33.

The column type 2 is arranged at the lower part of the column base structure 1. The lower part of the pillar type 2 is made of the foundation concrete 21. The foundation concrete 21 is formed by injecting fluid concrete into a form (not shown) and solidifying it. As will be described later, a plurality of reinforcing bars are buried in the foundation concrete 21. Two inner anchor bolts 27 and two outer anchor bolts 29 project from the upper surface 21a of the foundation concrete 21 and extend in the vertical direction. At least a part of the foundation concrete 21 is buried in the ground.

The pillar material 31 is a steel material and constitutes a part of the building. The base plate 33 is welded to the lower end of the pillar 31. The base plate 33 is a plate-shaped member having a substantially square shape in a plan view and having a predetermined thickness. As will be described later, the base plate 33 is formed with two inner through holes 35 and two outer through holes 37 (see FIG. 2).

The column base structure 1 is configured by fixing the column member 31 to the column type 2. Specifically, the pillar member 31 is arranged so as to extend in the vertical direction, the inner anchor bolt 27 is inserted into the inner through hole 35 of the base plate 33, and the outer anchor bolt 29 is inserted into the inner through hole 35 of the base plate 33. As a result, the inner anchor bolt 27 and the outer anchor bolt 29 project from the upper surface 33a of the base plate 33.

A grout 4 is provided between the upper surface 21a of the foundation concrete 21 and the lower surface 33b of the base plate 33. Even if the upper surface 21a of the foundation concrete 21 is uneven, the grout 4 is provided to form a flat surface, and the base plate 33 is placed on the grout 4, so that the pillar 31 can be more accurately vertically oriented. It will be possible to arrange it so that it extends.

Washers 5a and 5b are arranged on the upper surface 33a of the base plate 33 by inserting the inner anchor bolts 27 and the outer anchor bolts 29. Further, by screwing the nut 91 into the inner anchor bolt 27 and the outer anchor bolt 29, the nut 91 presses the base plate 33 toward the pillar type 2 side via the washers 5a and 5b. As a result, the pillar member 31 is fixed to the inner anchor bolt 27 and the outer anchor bolt 29 via the base plate 33, and is erected above the pillar mold 2. The column base structure 1 is referred to as an "exposed type column base structure" because the column member 31 is exposed without being embedded in the foundation concrete 21 of the column type 2.

Next, the column base structure 1 will be described in detail with reference to FIGS. 2 to 6. FIG. 2 is a side view showing the column base structure 1. FIG. 3 is a cross-sectional view showing a section III-III of FIG. FIG. 4 is a cross-sectional view showing the IV-IV cross section of FIG. 2 to 4 schematically show the column base structure 1 by cross-sectionally viewing or seeing through a part of the members for easy understanding. FIG. 5 is a perspective view showing washers 5a and 5b, and shows washers 5a and 5b from two directions. 6 (A) is a plan view showing the inflow restricting member 6, and FIG. 6 (B) is a cross-sectional view showing the VIB-VIB cross section of FIG. 6 (A).

As shown in FIGS. 2 and 4, the rising bar 23, the hoop bar 25, the inner anchor bolt 27, and the outer anchor bolt 29 are embedded in the foundation concrete 21 of the column type 2. ..

The twelve rising bars 23 are arranged along the outer shape of the foundation concrete 21 so as to be spaced apart from each other in the horizontal direction. Each rising bar 23 extends in the vertical direction. The hoop muscles 25 surround the rising muscles 23 and are arranged vertically spaced apart from each other. The number of riser bars 23 and hoop bars 25 is appropriately set according to the building or the like to be supported.

The inner anchor bolt 27 and the outer anchor bolt 29 are arranged on the central side of the foundation concrete 21 with respect to the rising bar 23 and the hoop bar 25. Both the inner anchor bolt 27 and the outer anchor bolt 29 are arranged so as to extend in the vertical direction. The outer anchor bolt 29 is provided outside the building than the inner anchor bolt 27. As shown in FIG. 2, the inner anchor bolts 27 and the outer anchor bolts 29 have lower portions 27a and 29a embedded in the foundation concrete 21 and upper portions 27b and 29b protruding from the upper surface 21a of the foundation concrete 21. Male threads are formed on the outer peripheral surfaces of the upper portions 27b and 29b.

As described above, a grout 4 is provided between the upper surface 21a of the foundation concrete 21 and the lower surface 33b of the base plate 33. The grout 4 is formed by injecting a fluid mortar between the upper surface 21a of the foundation concrete 21 and the lower surface 33b of the base plate 33 and solidifying it. The mortar used has excellent fluidity and a relatively small amount of shrinkage due to solidification. The compressive strength of the grout 4 (for example, 40 to 60 N / mm2) is larger than the compressive strength of the foundation concrete 21 (for example, 18 to 30 N / mm2).

As shown in FIG. 2, an inflow control member 6 is embedded in the grout 4. Specifically, the inflow control member 6 is embedded in the solidified grout 4, and the lower portion of the inflow control member 6 is covered with the grout 4. As shown in FIG. 6, the inflow control member 6 has a shielding plate 61 and a spring 67.

The shielding plate 61 has a disk shape, and its diameter is larger than the diameter of the outer through hole 37. A shielding plate through hole 63 is formed in the central portion of the shielding plate 61. The shield plate through hole 63 penetrates the shield plate 61 in the thickness direction, and its diameter is slightly larger than the diameter of the outer anchor bolt 29. A brush 65 is provided inside the shielding plate through hole 63. The brush 65 is an example of a ventilation unit according to the present invention. The brush 65 is a fibrous member extending from the inner peripheral surface of the shielding plate through hole 63 toward the central portion of the shielding plate through hole 63.

The spring 67 is an example of a pressure welding member according to the present invention. The spring 67 is a spiral spring made of a metal material, and is fixed to the lower surface of the shielding plate 61. The spring 67 expands and contracts in the vertical direction, and generates a reaction force according to the amount of expansion and contraction.

The washer 5a through which the inner anchor bolt 27 is inserted and the washer 5b through which the outer anchor bolt 29 is inserted have the same shape. As shown in FIG. 5, the washers 5a and 5b have a washer body 51. A recess 53 is formed on the lower surface side of the washer body 51. Further, the washer main body 51 is formed with a first through hole 55 and a second through hole 57 penetrating from the upper surface side to the recess 53. The diameter of the first through hole 55 is larger than the diameter of the second through hole 57 and the diameters of the inner anchor bolt 27 and the outer anchor bolt 29.

Next, the manufacturing process of the column base structure 1 will be described with reference to FIGS. 7 to 9. 7 and 8 are explanatory views showing a manufacturing process of the column base structure 1. FIG. 7 shows a part of the process, and FIG. 8 shows the rest of the process. FIG. 9 is a side view showing the column base structure 1, and shows an enlarged view of the periphery of the outer through hole 37.

[Spacer placement process]
First, in the spacer arranging step shown in FIG. 7A, the spacer 41 is arranged on the upper surface 21a of the foundation concrete 21 of the pillar type 2. The spacer 41 is formed of mortar and has a disk shape having a thickness of, for example, 30 mm. The mortar is of the same species used for the formation of grout 4. The diameter of the spacer 41 is smaller than the length of one side of the base plate 33. The spacer 41 is arranged closer to the center of the foundation concrete 21 than the inner anchor bolt 27 and the outer anchor bolt 29.

[Regulatory member placement process]
Next, in the restricting member arranging step shown in FIG. 7B, the inflow restricting member 6 is arranged on the upper surface 21a of the foundation concrete 21 of the pillar type 2. The inflow control member 6 is arranged by inserting the outer anchor bolt 29 into the shield plate through hole 63 and the spring 67 of the shield plate 61. The brush 65 of the inflow control member 6 is arranged between the inner side surface of the shielding plate through hole 63 and the outer anchor bolt 29. The spring 67 comes into contact with the upper surface 21a of the foundation concrete 21, and the shielding plate 61 is arranged above the upper surface 41a of the spacer 41.

[Erecting process]
Next, in the erection process shown in FIG. 7C, the pillar member 31 is arranged above the pillar mold 2. At this time, the pillar member 31 moves downward until the lower surface 33b of the base plate 33 comes into contact with the upper surface 41a of the spacer 41. As a result, the lower surface 33b of the base plate 33 and the upper surface of the upper surface 21a of the foundation concrete 21 face each other with the spacer 41 interposed therebetween, and a space C is formed between them. Further, the inner anchor bolt 27 is inserted into the inner through hole 35 of the base plate 33, the outer anchor bolt 29 is inserted into the outer through hole 37, and the upper portions 27b and 29b are arranged above the base plate 33.

Further, when the base plate 33 moves downward, its lower surface 33b presses the shielding plate 61 of the inflow control member 6 downward. As a result, the spring 67 of the inflow control member 6 is compressed to generate a reaction force, and the shielding plate 61 is pressed against the lower surface 33b of the base plate 33. The outer through hole 37 is shielded from below by the shielding plate 61.

[Fixing process]
Next, in the fixing step shown in FIG. 8A, the base plate 33 is fixed by the nut 91. Specifically, first, the upper portion 27b of the inner anchor bolt 27 and the upper portion 29b of the outer anchor bolt 29 are inserted into the first through holes 55 of the washers 5a and 5b, and the washers 5a and 5b are inserted into the upper surface 33a of the base plate 33. Is placed. The recess 53 forms a space between the washers 5a and 5b and the upper surface 33a of the base plate 33.

Further, two nuts 91 are screwed into each of the upper portion 27b of the inner anchor bolt 27 and the upper portion 29b of the outer anchor bolt 29. The lower nut 91 presses the base plate 33 downward via the washers 5a and 5b. As a result, the base plate 33 is pressed against the spacer 41 and fixed to the pillar type 2. The upper nut 91 presses the lower nut 91 and suppresses its loosening.

[Filling process]
Next, in the filling step shown in FIG. 8B, the space C is surrounded by the mold 93, and the unsolidified grout 4 is injected from the injector 95 into the second through hole 57 of the washer 5a. The injected grout 4 flows through the space formed between the washer 5a and the upper surface 33a of the base plate 33, passes through the inner through hole 35 of the base plate 33, and flows into the space C.

The grout that has flowed into space C flows toward the outside of the building, as indicated by the dashed arrow. As a result, the spacer 41, the inner anchor bolt 27, and the outer anchor bolt 29 arranged in the space C are embedded in the grout 4.

At this time, the air in the space C also flows toward the outside of the building by being pressurized by the grout flowing through the space C. Air flows into the inside of the spring 67 of the inflow control member 6 and passes through the brush 65 (see FIG. 6). The air further passes through the outer through hole 37 of the base plate 33, flows into the space formed between the washer 5b and the upper surface 33a of the base plate 33, and is discharged from the second through hole 57.

On the other hand, the inflow of the unsolidified grout 4 into the outer through hole 37 of the base plate 33 is regulated by the shielding plate 61 and the brush 65. That is, the brush 65 allows air to pass through, but prevents the grout 4 from passing through. Therefore, when the space C is filled with the grout 4, it becomes difficult to inject the grout 4 from the injector 95.

[Complete]
After the completion of the filling step, the grout 4 is cured for a predetermined time and solidified. After the grout 4 is solidified, the formwork 93 is removed as shown in FIG. 8C to complete the column base structure 1.

An inner grout 43, which is a solidified grout, is provided between the inner side surface of the inner through hole 35 of the base plate 33 and the inner anchor bolt 27. The inner grout 43 has an annular shape and surrounds the inner anchor bolt 27. The inner anchor bolt 27 is fixed to the base plate 33 by the inner grout 43.

On the other hand, around the outer through hole 37 of the base plate 33, as shown in FIG. 9, the grout 4 is not provided above the shielding plate 61. A gap 39 in which the grout 4 is not provided is formed between the inner side surface of the outer through hole 37 and the outer anchor bolt 29.

Next, the action and effect of the column base structure 1 will be described.

According to the configuration of the column base structure 1, when the building is vibrated due to an earthquake or the like, an external force acts from the column member 31 to the inner anchor bolt 27 via the base plate 33 and the inner grout 43. Since the base plate 33 receives a reaction force from the inner anchor bolt 27 via the inner grout 43, the movement of the base plate 33 is suppressed.

On the other hand, a gap 39 in which the grout 4 is not provided is formed between the inner side surface of the outer through hole 37 and the outer anchor bolt 29. Therefore, the action of the external force on the outer anchor bolt 29 is suppressed until the base plate 33 moves by a predetermined amount and the outer through hole 37 and the outer anchor bolt 29 come into contact with each other. As a result, the cone-shaped fracture of the foundation concrete 21 can be suppressed.

An inner grout 43 is provided between the inner side surface of the inner through hole 35 and the inner anchor bolt 27. According to this configuration, when the grout 4 is provided in the space C between the upper surface 21a of the foundation concrete 21 and the lower surface 33b of the base plate 33, the grout 4 is provided with the inner side surface of the inner through hole 35 and the inner anchor bolt 27. It can be made to flow in between. That is, it is possible to arrange the grout 4 in the space C between the upper surface 21a of the foundation concrete 21 and the lower surface 33b of the base plate 33 and fix the inner anchor bolt 27 to the base plate 33 in the same process.

An inflow control member 6 that regulates the inflow of the unsolidified grout 4 into the outer through hole 37 is arranged around the outer through hole 37. According to this configuration, when the unsolidified grout 4 is injected into the space C between the upper surface 21a of the foundation concrete 21 and the lower surface 33b of the base plate 33, the grout 4 is the inner side surface and the outer anchor of the outer through hole 37. The inflow between the bolt 29 and the bolt 29 can be regulated by the inflow regulating member 6. As a result, it becomes possible to surely form the void 39.

The inflow control member 6 has a shielding plate 61 arranged below the base plate 33, and the shielding plate 61 shields the outer through hole 37. According to this configuration, the inflow of the grout 4 between the inner side surface of the outer through hole 37 and the outer anchor bolt 29 can be regulated by the shielding plate 61. As a result, the void 39 can be reliably formed.

The inflow control member 6 has a spring 67 that presses the shielding plate 61 against the lower surface 33b of the base plate 33. According to this configuration, the outer through hole 37 can be reliably shielded by the shielding plate 61, and the inflow of the grout 4 between the inner side surface of the outer through hole 37 and the outer anchor bolt 29 can be restricted. As a result, the void 39 can be reliably formed.

The shielding plate 61 is formed with a shielding plate through hole 63 through which the outer anchor bolt 29 is inserted, and has a brush 65 inside the shielding plate through hole 63 that restricts the passage of the grout 4 while allowing the passage of air. May be. According to this configuration, when the unsolidified grout 4 is injected into the space C between the upper surface 21a of the foundation concrete 21 and the lower surface 33b of the base plate 33, air can be discharged from the space C through the brush 65. can. As a result, the void 39 can be formed without hindering the filling of the grout into the space C.

In the regulation member arranging step, the shielding plate 61 that shields the outer through hole 37 may be arranged below the base plate 33. According to this manufacturing method, the inflow of grout 4 between the inner side surface of the outer through hole 37 and the outer anchor bolt 29 can be regulated by the shielding plate 61. As a result, the void 39 can be reliably formed.

Next, another embodiment of the inflow control member according to the present invention will be described with reference to FIG. FIG. 10 is a perspective view showing the inflow control member 6A according to another embodiment.

The inflow control member 6A has a pressure contact member different from that of the above-mentioned inflow control member 6, but is embedded in the grout 4 in the same manner as the inflow control member 6. Among the inflow control members 6A, the same components as those of the inflow control member 6 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

The inflow control member 6A has three legs 69 as pressure contact members. The three legs 69 are separated from each other and are formed so as to extend downward from the shielding plate 61. The legs 69 have elasticity and generate a reaction force by being deformed so as to be opened (that is, separated from each other) by receiving an external force.

In the exposed column base structure (not shown) using the inflow control member 6A, the inflow control member 6A is arranged in place of the inflow control member 6 in the above-mentioned regulation member arrangement step (see FIG. 7B). The leg portion 69 is in contact with the upper surface 21a of the foundation concrete 21, and the shielding plate 61 is arranged above the upper surface 41a of the spacer 41.

In the next erection step (see FIG. 7C), when the base plate 33 moves downward, its lower surface 33b presses the shielding plate 61 of the inflow control member 6A downward. As a result, the leg portion 69 of the inflow control member 6A opens to generate a reaction force, and the shielding plate 61 is pressed against the lower surface 33b of the base plate 33. The outer through hole 37 is shielded from below by the shielding plate 61.

Next, still another embodiment of the inflow control member according to the present invention will be described with reference to FIG. 11. FIG. 11 is a side view showing an exposed column base structure 1B provided with an inflow control member 6B according to another embodiment.

The inflow control member 6B is a member having flexibility and breathability. As the inflow control member 6B, for example, a fibrous material such as glass wool or a porous body such as sponge can be used.

In the exposed column base structure 1B using the inflow control member 6B, the inflow control member 6B is arranged in place of the inflow control member 6 in the above-mentioned regulation member arrangement step (see FIG. 7B). The inflow control member 6B is arranged in the gap 39.

According to this configuration, the inflow of the grout 4 between the inner side surface of the outer through hole 37 and the outer anchor bolt 29 can be reliably regulated by the inflow restricting member 6B arranged therein. Further, when the unsolidified grout 4 is injected into the space C between the upper surface 21a of the foundation concrete 21 and the lower surface 33b of the base plate 33, air can be discharged from the space C via the inflow control member 6B. .. As a result, the void 39 can be formed without hindering the filling of the grout into the space C.

Further, when the base plate 33 moves, the inflow restricting member 6B bends, so that the action of an external force on the outer anchor bolt 29 is suppressed. As a result, the cone-shaped fracture of the foundation concrete 21 can be suppressed.

Next, still another embodiment of the inflow control member according to the present invention will be described with reference to FIGS. 12 and 13. FIG. 12 is a perspective view showing a washer 6C which is an inflow control member according to another embodiment, and shows the washer 6C from two directions. FIG. 13 is a side view showing an exposed column base structure 1C provided with a washer 6C.

The washer 6C is used in place of the washer 5b (see FIG. 2 and the like) through which the outer anchor bolt 29 is inserted. On the other hand, the washer 5a (see FIG. 2 and the like) through which the inner anchor bolt 27 is inserted is used in the same manner as in the above-described embodiment. Among the components of the washer 6C, the same components as those of the washers 5a and 5b are designated by the same reference numerals, and duplicate description will be omitted.

As shown in FIG. 12, the washer 6C has a first through hole 55 formed in the washer main body 51. The first through hole 55 of the washer 6C is an example of the washer through hole according to the present invention. On the other hand, the washer main body 51 is not formed with the second through hole 57 (see FIG. 5). The washer 6C has a ventilation regulating portion 59 instead of the second through hole 57.

As shown in FIG. 13, the washer 6C is arranged on the upper surface 33a of the base plate 33 by inserting the outer anchor bolt 29 into the first through hole 55. Further, by screwing the nut 91 into the outer anchor bolt 29, the gap between the inner side surface of the first through hole 55 and the outer anchor bolt 29 is shielded from above by the nut 91.

The space formed between the washer 6C and the upper surface 33a of the base plate 33 is shielded from the upper portion by the provision of the ventilation restricting portion 59. That is, air tends to stay in the space.

According to this configuration, air stays in the space formed between the washer 6C and the upper surface 33a of the base plate 33. The retention of air above the outer through hole 37 regulates the discharge of air through the outer through hole 37. By appropriately performing such regulation, when the unsolidified grout 4 is injected into the space C between the upper surface 21a of the foundation concrete 21 and the lower surface 33b of the base plate 33, the inner side surface and the outer side of the outer through hole 37 are injected. The inflow of grout 4 to and from the anchor bolt 29 can be restricted. As a result, it becomes possible to surely form the void 39.

When the washer 6C is used as the inflow control member, the step shown in FIG. 7B can be omitted from the above-mentioned manufacturing steps. Further, the process shown in FIG. 8A as the fixing process also serves as the regulating member arranging process.

The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. That is, those skilled in the art with appropriate design changes to these specific examples are also included in the scope of the present invention as long as they have the features of the present invention. Each element provided in each of the above-mentioned specific examples, its arrangement, material, condition, shape, size, and the like are not limited to those exemplified, and can be appropriately changed.

For example, the inflow control members 6 and 6A described above have a brush 65 as a ventilation portion. However, the ventilation portion according to the present invention is not limited to this aspect. The ventilation portion may be, for example, a slit formed on the inner peripheral surface of the shielding plate through hole.

For example, the washer 6C described above is provided with a ventilation restricting portion 59 because the second through hole 57 is not formed in the washer main body 51. However, the ventilation control unit according to the present invention is not limited to this aspect. The ventilation restricting portion may be provided, for example, by closing the second through hole 57 formed in the washer main body 51 with a plug.

For example, in the above-described embodiment, the inner anchor bolt 27 is fixed to the base plate 33 by the inner grout 43. However, the fixing of the inner anchor bolt to the base plate according to the present invention is not limited to this aspect. For example, the inner anchor bolt may be fixed to the base plate by arranging a filler member made of a resin material or a metal material between the inner side surface of the inner through hole and the inner anchor bolt. Further, the inner anchor bolt may be fixed to the base plate by welding the washer through which the inner anchor bolt is inserted to the base plate.

For example, the method for manufacturing the column base structure 1 described above includes a regulating member arranging step (see FIG. 7A) as a step following the spacer arranging step (see FIG. 7A). However, the method for manufacturing the exposed column base structure according to the present invention is not limited to this aspect. The restricting member arranging step may be, for example, a step performed prior to the spacer arranging step. Further, the inflow control member may be arranged at the same time as the spacer.

For example, the column base structure 1 described above includes two inner anchor bolts 27 and outer anchor bolts 29, respectively. However, the exposed column base structure according to the present invention is not limited to this aspect. For example, the exposed column base structure according to the present invention may include three or more inner anchor bolts and outer anchor bolts, respectively.

1,1B, 1C: Exposed type pillar base structure 2: Pillar type 21: Foundation concrete 21a: Top surface 27 (of foundation concrete): Inner anchor bolt 27a: Lower part 27b (of inner anchor bolt): Upper part (of inner anchor bolt) 29: Outer anchor bolt 29a: Lower part (of outer anchor bolt) 29b: Upper part (of outer anchor bolt) 31: Pillar 33: Base plate 33a: Upper surface 33b (of base plate): Lower surface 35 (of base plate): Inner through hole 37 : Outer through hole 39: Void 4: Grout 41: Spacer 43: Inner grout 5a, 5b, 6C: Seat 51: Seat metal body 59: Ventilation control part 6, 6A, 6B: Inflow control member 6C: Seat (inflow control member)
61: Shielding plate 63: Shielding plate through hole 65: Brush (ventilation part)
67: Spring (contact member)
69: Leg (contact member)

Claims (10)

It is an exposed column base structure that supports the building,
It has a foundation concrete, an inner anchor bolt, and an outer anchor bolt provided outside the building from the inner anchor bolt. The inner anchor bolt and the outer anchor bolt have a lower portion of the foundation concrete. Anchor bolts, which are buried and the upper part of which protrudes from the upper surface of the foundation concrete,
Pillar material extending in the vertical direction and
A base plate fixed to the lower end of the pillar material and formed with an inner through hole and an outer through hole penetrating between the upper surface and the lower surface, and the upper portion of the inner anchor bolt is inserted into the inner through hole. A base plate fixed to the upper part of the inner anchor bolt and the outer anchor bolt by inserting the upper part of the outer anchor bolt into the outer through hole.
A grout provided in the space between the upper surface of the foundation concrete and the lower surface of the base plate.
The inner anchor bolt is fixed without a gap between the inner through hole of the base plate and the inner through hole.
An exposed column base structure in which a gap without grout is formed between the inner side surface of the outer through hole and the outer anchor bolt. It is an exposed column base structure that supports the building,
It has a foundation concrete, an inner anchor bolt, and an outer anchor bolt provided outside the building from the inner anchor bolt. The inner anchor bolt and the outer anchor bolt have a lower portion of the foundation concrete. Anchor bolts, which are buried and the upper part of which protrudes from the upper surface of the foundation concrete,
Pillar material extending in the vertical direction and
A base plate fixed to the lower end of the pillar material and formed with an inner through hole and an outer through hole penetrating between the upper surface and the lower surface, and the upper portion of the inner anchor bolt is inserted into the inner through hole. A base plate fixed to the upper part of the inner anchor bolt and the outer anchor bolt by inserting the upper part of the outer anchor bolt into the outer through hole.
A grout provided in the space between the upper surface of the foundation concrete and the lower surface of the base plate.
The inner anchor bolt is fixed to the base plate by arranging a grout or a filler member between the inner side surface of the inner through hole and the inner anchor bolt, or a washer through which the inner anchor bolt is inserted. It is fixed by welding to the base plate and
An exposed column base structure in which a gap without grout is formed between the inner side surface of the outer through hole and the outer anchor bolt. The exposed column base structure according to claim 1, wherein a grout is provided between the inner side surface of the inner through hole and the inner anchor bolt. The exposed column base structure according to any one of claims 1 to 3, wherein an inflow control member for restricting the inflow of unsolidified grout into the outer through hole is arranged around the outer through hole. .. The inflow control member has a shielding plate arranged below the base plate.
The exposed column base structure according to claim 4 , wherein the shielding plate shields the outer through hole. The exposed column base structure according to claim 5 , wherein the inflow restricting member has a pressure contact member that presses the shield plate against the lower surface of the base plate. The shielding plate is formed with a shielding plate through hole through which the outer anchor bolt is inserted.
The exposed column base structure according to claim 5 or 6 , wherein the inside of the shielding plate through hole has a ventilation portion that restricts the passage of grout while allowing the passage of air. The exposed column base structure according to claim 4 , wherein the inflow control member has flexibility and is arranged in the void. The inflow control member has a washer placed on the upper surface of the base plate.
The exposed column according to claim 4 , wherein the washer is formed with a washer through hole through which the outer anchor bolt is inserted and a ventilation restricting portion that shields the periphery of the outer through hole to regulate ventilation. Leg structure. There is a manufacturing method of the exposed column base structure that supports the building,
It has a foundation concrete, an inner anchor bolt, and an outer anchor bolt provided outside the building from the inner anchor bolt. The inner anchor bolt and the outer anchor bolt have a lower portion of the foundation concrete. A spacer arranging step of arranging spacers on the upper surface of a pillar shape that is buried and the upper part projects from the upper surface of the foundation concrete.
A pillar material having a base plate fixed to the lower end is placed above the pillar shape, and the upper portion of the inner anchor bolt is inserted into the inner through hole formed in the base plate, and the outer through hole formed in the base plate is inserted. An erection step in which the upper portion of the outer anchor bolt is inserted and the lower surface of the base plate and the upper surface of the spacer are brought into contact with each other.
A fixing step of fixing the base plate by fastening bolts to the upper part of the inner anchor bolt and the outer anchor bolt, respectively.
It has a filling step of filling the space between the upper surface of the foundation concrete and the lower surface of the base plate with unsolidified grout.
An exposed column base structure having a restricting member arranging step of arranging an inflow restricting member for restricting the inflow of unsolidified grout into the outer through hole around the outer through hole prior to the filling step. Manufacturing method.

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