JP7423418B2 - Column base fixed structure, building, and construction method of column base fixed structure - Google Patents

Description

The present invention relates to a column base fixing structure, a building, and a method for constructing a column base fixing structure, and particularly to a column base fixing structure, a building, and a column base fixing structure formed using a column base fixing formwork buried in a foundation. Concerning construction methods for fixed structures.

Conventionally, when fixing the column base of a building, etc., the column base is erected on the top surface of the poured concrete, and then concrete is poured around the column base to establish the bottom end of the column base as a foundation. A column base fixing structure that is embedded in a beam is known. In addition, a column base fixing structure is constructed by burying an embedded column base case with a cylindrical container structure with an open top surface in the foundation beam concrete, and inserting and fixing the lower end of the steel column into the embedded column base case. Are known.

According to the column pedestal fixing structure disclosed in Patent Document 1, the embedded column pedestal case is installed at the column erecting position on the waste concrete via the installation leg. Then, the foundation beam concrete is placed in a boxed state so that the flange portion provided at the upper end of the embedded column pedestal case is exposed, and the lower part of the steel column is inserted into the embedded column pedestal case. A flange is fixed to the outer periphery of the steel column, and the flange is embedded and overlapped with the flange part of the column base case. A vertical push bolt is screwed into the flange of the steel column in the vertical direction, and a horizontal push bolt is screwed into the flange of the embedded column base case in the horizontal direction. The height of the steel column is adjusted by operating the vertical push bolt, and the horizontal centering is adjusted by adjusting the horizontal push bolt. Thereafter, the flange of the steel column and the flange portion of the embedded column base are fastened with fixing bolts, and the gap between the embedded column base case and the steel column is filled with mortar to fix the steel column.

Japanese Patent Application Publication No. 9-310354

The column base fixing structure disclosed in Patent Document 1 is designed to transmit the load from the steel column to the foundation beam concrete in order to improve the bonding force and bearing effect between the embedded column base case and the foundation beam concrete. It has a cylindrical container structure that ensures strength. In addition, embedded column base cases require stud bolts to be installed on the sides to transfer the load between the foundation beam concrete and the column base case, which poses the problem that the structure of embedded column base cases is complex and costly. there were.

In addition, the column base fixing structure disclosed in Patent Document 1 includes a plurality of vertical push bolts on the flange of the steel column in order to adjust the position of the steel column, and horizontal push bolts on the flange of the embedded column base case. Equipped with multiple. Furthermore, after adjusting the position of the steel column, the flange of the steel column and the flange portion of the embedded column base are fastened together with fixing bolts, and the flange and flange portion are embedded in the foundation beam concrete. Therefore, it is necessary to form a recess in the foundation beam concrete so that the periphery of the upper end of the column pedestal case is boxed out so that the flange portion at the upper end of the column pedestal case is exposed. After adjusting the position of the steel columns and tightening the fixing bolts, concrete is poured into the recesses of the foundation beam concrete where the flanges and flange sections are placed to cover the flanges and flange sections, which requires many steps during construction. There was a problem.

The present invention has been made to solve the above problems, and by simplifying the structure of the formwork that forms the insertion hole provided in the foundation for inserting the column base, it is possible to attach the column base to the foundation. It is an object of the present invention to provide a column base fixing structure, a building, and a construction method for the column base fixing structure, which can facilitate the construction of the column base fixing structure while ensuring fixing strength.

The column base fixing structure according to the present invention includes a formwork surrounding the lower end of the column base, a foundation cast around the formwork, and a reinforcing steel structure surrounding the sides of the formwork. , a foundation formwork surrounding the formwork and the side of the reinforcing steel structure, the formwork having a hole that communicates between the inside and outside of the formwork, and the formwork having a hole that communicates with the inside and outside of the formwork, and forming a bottom end of the column base. A partition member surrounding the sides and a structural member supporting the partition member are provided, a gap between the lower end of the column base and the formwork is filled with a filler , and the base formwork includes: The present invention includes a first foundation formwork installed on the surface of the waste concrete, and the first foundation formwork is formed into a cylindrical shape using a steel plate .

A building according to the present invention includes the column base fixing structure described above.

A method for constructing a column base fixing structure according to the present invention includes a formwork installation step of installing a formwork comprising a partition member having a hole that communicates the inside and outside of an enclosed space and a structural member that supports the partition member. a reinforcing reinforcing bar structure installation step of installing a reinforcing reinforcing bar structure including main bars extending in the vertical direction and hoop bars extending in the horizontal direction and surrounding the formwork on the sides of the formwork; A foundation formwork installation process in which a foundation formwork surrounding the sides is installed, a foundation pouring process in which a foundation is placed around the formwork, and a column erected by inserting column bases inside the formwork. and an injection step of injecting a filler into the gap between the formwork and the column base , the foundation formwork comprising a first foundation formwork installed on the surface of the sacrificial concrete, The first foundation formwork is formed into a cylindrical shape using a steel plate, and the foundation pouring step includes a first foundation pouring step of pouring the foundation into the first foundation formwork.

According to the present invention, since the partition member is formed with a hole structure that communicates the inside and outside of the formwork, the filler filled in the gap between the formwork and the lower end of the column leg is It solidifies in contact with the foundation formed on the outside. As a result, the filling material and the foundation are directly connected, so the column base fixing structure eliminates the need to provide the formwork with members such as stud bolts that transmit the load to the foundation, and the column base and formwork are fixed to each other. The column base can be embedded and fixed in the foundation with a simple structure, without requiring any additional structure.

FIG. 2 is a top view of the column base fixing structure 100 according to the first embodiment. FIG. 2 is a cross-sectional view of the column base fixing structure 100 of FIG. 1. FIG. FIG. 2 is a perspective view of the lower end of the column pedestal 50 in FIG. 1. FIG. 3 is a perspective view of the formwork 10 of FIG. 2. FIG. FIG. 2 is a side view of the formwork 10 of the column base fixing structure 100 according to the first embodiment. FIG. 2 is a cross-sectional view of the formwork 10 of the column base fixing structure 100 according to the first embodiment. FIG. 2 is a perspective view of the column base fixing structure 100 according to the first embodiment before a foundation 90 is formed. FIG. 7 is a perspective view showing a modification of the foundation formwork 94 used to form the foundation 90 of the column base fixing structure 100 according to the first embodiment. FIG. 7 is a plan view and a side view of a column pedestal 150 that is a modification of the column pedestal 50 of the column pedestal fixing structure 100 according to the first embodiment. FIG. 3 is a perspective view of a column pedestal 250 that is a modification of the column pedestal 50 of the column pedestal fixing structure 100 according to the first embodiment. FIG. 2 is a cross-sectional view of a column base fixing structure 200 according to a second embodiment. FIG. 7 is a cross-sectional view showing a state before a column base 250 of a column base fixing structure 200 according to a second embodiment is installed. FIG. 7 is a top view of a column base fixing structure 300 according to a third embodiment. FIG. 3 is a cross-sectional view of a column base fixing structure 300 according to a third embodiment. FIG. 7 is a perspective view of the column base fixing structure 300 according to the third embodiment before a foundation 390 is formed.

Embodiments of the present invention will be described below based on the drawings. Note that in the following drawings, the relative dimensional relationship, shape, etc. of each member may differ from the actual one. In addition, in the following drawings, parts with the same reference numerals are the same or equivalent, and this is common throughout the entire specification. In addition, to facilitate understanding, we use terms that indicate directions (for example, "top", "bottom", "right", "left", "front", "back", etc.), but these notations are as follows: This is only described for convenience of explanation, and the arrangement and orientation of each component are not limited. Moreover, the forms of the constituent elements appearing in the entire specification are merely examples, and the present invention is not limited to only the description within the specification. In particular, the combinations of components are not limited to those in each embodiment, and components described in other embodiments can be applied to other embodiments.

Embodiment 1.
FIG. 1 is a top view of a column base fixing structure 100 according to the first embodiment. FIG. 2 is a cross-sectional view of the column base fixing structure 100 of FIG. 1. FIG. 3 is a perspective view of the lower end of the column pedestal 50 in FIG. 1. FIG. 4 is a perspective view of the formwork 10 of FIG. 2. Note that FIG. 2 shows a cross section taken along the line AA in FIG. The column pedestal fixing structure 100 is for embedding the lower end portion 51 of the column pedestal 50 in the foundation 90 and fixing the column pedestal 50 to the foundation 90. The column pedestal fixing structure 100 is used, for example, in the construction of a steel frame building, and is used at the connection portion between the lower end of the column pedestal of the main frame of the steel frame building and the foundation 90. By embedding and fixing the lower end portion 51 of the column pedestal 50 into the foundation 90, the degree of fixation of the column pedestal 50 to the foundation 90 is improved compared to an exposed column pedestal. Therefore, a building using the column pedestal 50 has improved strength and rigidity, or the column pedestal 50 can be made thinner than when an exposed column pedestal is used. In addition, in the following description, the direction in which the column base 50 extends will be described as the up-down direction.

(Overall structure)
As shown in FIG. 2, the column base fixing structure 100 has a formwork 10 embedded inside a foundation 90. The lower end portion 51 of the column base 50 is disposed inside the formwork 10 and is laterally surrounded by the structural member 11 and the partition member 20 that constitute the formwork 10. Further, the partition member 20 is also arranged below the lower end portion 51 of the column base 50. The formwork 10 forms a hole 60 that opens upward in the base 90. The lower end 51 of the column base 50 is inserted into the hole 60. A gap 61 between the lower end 51 of the column base 50 inserted into the hole 60 and the formwork 10 is filled with a filler. In the first embodiment, the material used as the filler 91 forming the foundation 90 and the filler 95 filled in the hole 60 is concrete, but it may be made of other materials.

As shown in FIG. 1, the foundation 90 is circular in plan view. The foundation 90 is formed by filling concrete as a filler 91 inside a foundation form 94 (see FIG. 7A or FIG. 7B) installed on top of sacrificial concrete 92 to form the foundation. Inside the foundation formwork 94, before filling with concrete, a bottom reinforcing bar 80 is placed above the sacrificial concrete 92, and the formwork 10 is also placed on the top surface of the sacrificial concrete 92 and fixed by fixing means such as oar anchors 83. ing. Since the formwork 10 is fixed to the sacrificial concrete 92, its position does not change when the base formwork 94 is filled with the filler 91. In the first embodiment, the base formwork 94 is formed in a circular shape in a plan view, and the foundation 90 is also circular in a plan view, but the shape is not limited to this form. The shape of the foundation 90 can be changed as necessary, such as an ellipse or a rectangle, for example.

(Column base 50)
As shown in FIG. 3, the column base 50 is made of H-beam steel having a web portion 56 and flange portions 57 formed at both ends thereof. An angle having an L-shaped cross section is fixed to the outer surface of the flange portion 57 as a support member 52 at the upper part of the lower end portion 51 of the column base 50 . The support member 52 is located above the upper surface 93 of the foundation 90 and is connected to the foundation 90 in a state where the lower end 51 of the column base 50 is inserted into the hole 60 formed in the foundation 90. The support member 52 is fixed to the column base 50 by fixing one plate surface of an angle having an L-shaped cross section to the side surface of the flange portion 57 of the column base 50. The other plate surface of the angle that is the support member 52 is arranged at right angles to the side surface of the flange portion 57 of the column base 50 and is approximately parallel to the upper surface 93 of the foundation 90.

A protrusion 53 is formed at the lower end of the column base 50. The protruding portion 53 protrudes laterally from the side surface of the flange portion 57 of the column base 50. In the first embodiment, the protruding portion 53 is formed by joining a plate-like member to the side surface of the flange portion 57 by a joining means such as welding. However, the protrusion 53 is not limited to the form shown in FIG. 3. The protruding portion 53 may have any other form as long as it is formed to protrude from the side surface, such as a bolt fixed to the side surface of the flange portion 57, and is fixed to the lower end portion 51 of the column base 50. .

When the filler 95 is injected into the inside of the mold 10, the upper and lower portions of the protrusion 53 are filled with the filler. In the first embodiment, since concrete is injected into the formwork 10 as the filler 95, there is solidified concrete above the protrusion 53. When an upward pull-out load is applied to the column base 50, the pull-out load applied to the column base 50 is transmitted from the upper surface of the protrusion 53 of the column base 50 to the concrete located above the protrusion 53. Thereby, the column base fixing structure 100 can resist the load that causes the column base 50 to be pulled out upward.

The column base 50 includes a rib plate 54 below the support member 52. The rib plate 54 is formed by joining a plate-like member to a web portion 56 and two flange portions 57, and is installed with the plate surface facing up and down. The rib plate 54 is installed in a portion surrounded on three sides by the inner surface 57b of the flange portion 57 and the surface 56a of the web portion 56, and extends from the surface 56a of the web portion 56 to the tip 57a of the flange portion 57 in plan view. It has been extended.

When the filler 95 is injected inside the formwork 10, the filler 95 is filled in the upper and lower portions of the rib plate 54. In the first embodiment, since concrete is injected into the formwork 10 as the filler 95, there is solidified concrete below the rib plate 54. When a downward pushing load is applied to the column pedestal 50, the pushing load applied to the column pedestal 50 is transmitted from the lower surface of the rib plate 54 of the column pedestal 50 to the concrete located below the rib plate 54. Thereby, the column base fixing structure 100 can resist the load that forces the column base 50 downward.

(Formwork 10)
FIG. 5 is a side view of the formwork 10 of the column base fixing structure 100 according to the first embodiment. FIG. 6 is a sectional view of the formwork 10 of the column base fixing structure 100 according to the first embodiment. FIG. 6 shows a cross-sectional structure taken along the line BB in FIG. The formwork 10 is constructed by attaching a partition member 20 to a structural member 11. The structural member 11 includes four leg members 14 arranged along the direction in which the column base 50 extends, an upper frame member 12 attached to the upper end of the leg member 14, and a predetermined height from the lower end of the leg member 14. and a lower frame member 15 attached at the position. At the lower end of the leg member 14, the fixing member 13 can be fixed to the upper surface of the sacrificial concrete 92 using an oar anchor 83 or the like.

The upper frame member 12 is formed in a rectangular shape in plan view, and is arranged so as to connect the upper ends of two adjacent leg members 14 among the four leg members 14. The lower frame member 15 is also formed in a rectangular shape in plan view, and is arranged so as to connect adjacent leg members 14 at a predetermined height position from the upper surface of the concrete 92. The structural members 11 are each arranged at a position corresponding to the ridgeline of the rectangular parallelepiped, and are configured to form the ridgeline portion of the rectangular parallelepiped-shaped hole 60 formed in the foundation 90 . Partition members 20 are attached to positions corresponding to the side and bottom surfaces of the rectangular parallelepiped formed by the structural member 11. The partition member 20 is configured to form a side surface 62 and a bottom surface 63 of a rectangular parallelepiped-shaped hole 60 formed in the base 90 .

The formwork 10 may include a vertical support member 16 that connects the upper frame member 12 and the lower frame member 15. The vertical support member 16 extends in the vertical direction, and has both ends fixed to the upper frame member 12 and the lower frame member 15. Further, the formwork 10 may include a lateral support member 17 that connects adjacent leg members 14 at a position between the upper frame member 12 and the lower frame member 15. The lateral support member 17 extends horizontally and has both ends fixed to two adjacent leg members 14. The vertical support member 16 and the horizontal support member 17 are members that support the partition member 20 disposed on the side surface of the formwork 10 so that it does not deform. The vertical support member 16 and the horizontal support member 17 support the partition member 20 so that it does not deform when the filler 91 forming the foundation 90 is filled around the formwork 10.

(Partition member 20)
In the first embodiment, the partition member 20 is made of lath material. The lath material is, for example, an expanded metal lath in which a mesh is formed by making cuts extending in one predetermined direction in a thin metal plate and pulling the metal plate in a direction perpendicular to the cuts. Alternatively, the lath material may be a wire lath formed by knitting wire. However, in the partition member 20, the filling material 91 forming the foundation 90 does not flow into the inside of the formwork 10, and the filling material is injected into the inside of the formwork 10 (inside the hole 60 formed in the foundation 90). Other forms can be taken as long as the structure allows contact between the filler 95 and the filler 91 outside the formwork 10. For example, a metal plate with a plurality of holes formed therein so that the inside and outside of the formwork 10 communicate with each other may be used as the partition member 20 .

By providing the partition member 20, the column base fixing structure 100 can directly connect the filling material 91 on the outside of the formwork 10 and the filling material 95 on the inside of the formwork 10. Therefore, compared to the formwork of the conventional column base fixing structure in which the inside and outside of the partition member are blocked and the fillers 91 and 95 do not come into contact, the column base fixing structure 100 according to the first embodiment There is no need for structures such as stud bolts to ensure the bonding force between the formwork 10 and the foundation. In the column base fixing structure 100, the load applied to the column base 50 is transmitted to the filler material 95 located inside the formwork 10, and is directly transferred from the filler material inside the formwork 10 to the filler material 91 located outside the formwork 10. communicated. Therefore, in the column base fixing structure 100, the inner filler 95 and the outer filler 91 of the formwork 10 can work together to resist the load applied to the column base 50.

(Construction method of column base fixing structure 100)
A method of constructing the column base fixing structure 100 according to the first embodiment will be described below. First, a foundation formwork 94 for forming the foundation 90 and the bottom reinforcing bars 80 to be embedded inside the foundation 90 are placed on the sacrificial concrete 92 cast on the ground.

FIG. 7A is a perspective view of the column base fixing structure 100 according to the first embodiment before the foundation 90 is formed. FIG. 7B is a perspective view showing a modification of the foundation formwork 94 used to form the foundation 90 of the column base fixing structure 100 according to the first embodiment. As shown in FIGS. 7A and 7B, the formwork 10 is fixed on the sacrificial concrete 92. Note that the shape and structure of the foundation formwork 94 shown in FIG. 7A is an example, and is not limited to this form. For example, the base formwork 94 may be formed in a rectangular shape in plan view as shown in FIG. 7B, or may have another shape. In the first embodiment, as shown in FIG. 2, a hole 60 into which the lower end 51 of the column base 50 is inserted is formed above the bottom reinforcing bar 80 embedded in the lower part of the foundation 90. Therefore, although the formwork 10 is installed after the foundation formwork 94 and the bottom reinforcing bars 80 are installed, the order of installation can be changed as appropriate depending on the structure of the foundation formwork 94 and the bottom reinforcing bars 80. The process of installing the formwork 10 on the waste concrete 92 is referred to as a formwork installation process.

After the formwork 10 is installed and in a state where the filler 91 forming the foundation 90 can be injected into the foundation formwork 94, concrete is injected as the filler 91 around the formwork 10. As shown in FIG. 2, the filling material 91 forming the foundation 90 is filled so as to be substantially flush with the upper surface of the upper frame member 12 of the formwork 10. The process of pouring the foundation 90 around the formwork 10 is referred to as a foundation pouring process. Note that the process of installing the foundation formwork 94 on the waste concrete 92 is referred to as a foundation formwork installation process. The foundation formwork installation process is included in the foundation pouring process.

When the filler 91 forming the foundation 90 is cast, a hole 60 having a rectangular opening is formed in the upper surface 93 of the foundation 90. An anchor bolt 81 (see FIG. 2) is installed around the hole 60. The anchor bolt 81 is a driven anchor that is driven into and installed from the upper surface 93 of the foundation 90 that has been driven. The anchor bolts 81 can be installed with high precision by being installed after the foundation 90 is cast. However, the anchor bolt 81 may be fixed to a reinforcing bar or the like placed inside the foundation 90 before the foundation 90 is cast. This process is called an anchor bolt installation process.

After the anchor bolt 81 is installed in the foundation 90, the column base 50 is inserted into the hole 60 formed in the foundation 90. An anchor bolt 81 (see FIG. 2) is inserted into a through hole 52a (see FIG. 3) provided vertically through the end of the support member 52 of the column base 50. The position of the support member 52 in the height direction is adjusted by a nut 82 screwed onto an anchor bolt 81. The nut 82 is fixed at a desired height by a nut 86 that is threaded downward onto the anchor bolt 81. After the inclination and height of the column base 50 are adjusted, the support member 52 is fixed to the anchor bolt 81 by tightening the nut 85. Thereby, the column base 50 is connected to the foundation 90 via the anchor bolt 81 and positioned. Note that by forming the through hole 52a provided in the support member 52 larger than the outer diameter of the anchor bolt 81, the horizontal position of the column base 50 can also be adjusted. The column base fixing structure 100 may be configured to allow horizontal position adjustment depending on the installation accuracy of the anchor bolts 81. The above process is called a pillar-standing process. In addition, the process of adjusting the position of the column base 50 is particularly referred to as a column base position adjustment process. The column base position adjustment process is included in the column erection process.

After the column base 50 is erected in the hole 60 and the position of the column base 50 is adjusted, concrete is poured into the hole 60 as a filler 95. A gap 61 between the formwork 10 and the lower end 51 of the column base 50 is secured, and filling with the filler 95 is easy. Further, when the H-beam steel shown in FIG. 3 is used as the column base 50, the filler 95 can be injected from between the two flange portions 57 of the column base 50, so the work is easy. This process is called an injection process.

Since the column base 50 is connected to the foundation 90 via the anchor bolt 81 and fixed by tightening the nuts 82, 85, and 86, its position does not change even during the injection process.

(Function of column base fixing structure 100)
As described above, the column pedestal fixing structure 100 includes the formwork 10 surrounding the lower end 51 of the column pedestal 50, and the foundation 90 cast around the formwork 10. The formwork 10 includes a partition member 20 that has a hole that communicates the inside and outside of the formwork 10 and surrounds the lower end 51 of the column base 50, and a structural member 11 that supports the partition member 20. A gap 61 between the lower end 51 of the column base 50 and the formwork 10 is filled with a filler 95.
With this configuration, in the column pedestal fixing structure 100, the lower end portion 51 of the column pedestal 50 is fixed by the filler 95 inside the formwork 10 that is directly connected to the foundation 90. Therefore, the load applied to the column base 50 is directly transmitted to the foundation 90, and the column base fixing structure 100 can ensure the fixing strength of the column base 50. In addition, the formwork 10 has a simple structure and does not require any parts to ensure a bonding force with the foundation 90, so the cost is reduced, the weight is reduced, and installation is easy.

The partition member 20 is, for example, an expanded metal lath having a mesh structure. With this configuration, the inner filler 95 and the outer filler 91 of the formwork 10 come into contact through the plurality of holes formed by the network structure, so the contact area becomes large and the bonding Power increases. Moreover, the partition member 20 is lightweight due to its mesh structure, and the weight of the formwork 10 as a whole is also reduced.

The column base 50 includes a support member 52 that protrudes laterally above the upper surface 93 of the foundation 90. Support member 52 is connected to foundation 90. Thereby, the column base 50 is directly connected to and positioned with respect to the foundation 90, making it easy to achieve positional accuracy. The foundation 90 also includes anchor bolts 81 installed around the formwork 10. The support member 52 is connected to the foundation 90 via an anchor bolt 81. Thereby, the column base 50 can be easily positioned by fastening and fixing the support member 52 to the anchor bolt 81. Further, since the height position of the support member 52 can be adjusted by threading the nut 82 onto the anchor bolt 81, the height and inclination of the column base 50 can be easily adjusted. Further, since the column base 50 is fixed to the anchor bolt 81, positional shift does not occur when filling the hole 60 with the filler 95, and construction can be performed with high precision.

The column base 50 is made of H-shaped steel having a web portion 56 and flange portions 57 formed at both ends thereof. The column base 50 includes a plate-shaped rib plate 54 provided below the upper surface 93 of the foundation 90. The rib plate 54 is installed with its plate surface facing the direction in which the column base 50 is erected.

The column base 50 includes a protrusion 53 on the side surface. Further, the protruding portion 53 is formed below the upper surface 93 of the foundation 90. As a result, the load in the pullout direction applied to the column base 50 is transmitted to the filler 95 filled inside the formwork 10, so the column base fixing structure 100 can resist the load in the pullout direction of the column base 50. Can be done. By installing the protruding part 53 at the lower end of the lower end part 51 of the column base 50, the height dimension of the concrete located above the protruding part 53 increases. Therefore, the shear area of the concrete on which the pull-out load is applied can be increased, and the column base fixing structure 100 can more firmly fix the column base 50 against the pull-out load.

(Modified example)
FIG. 8 is a plan view and a side view of a column pedestal 150 that is a modification of the column pedestal 50 of the column pedestal fixing structure 100 according to the first embodiment. Note that FIG. 8(a) is a plan view, and FIG. 8(b) is a side view. The column base 50 used in the column base fixing structure 100 may be a column base 150 made of a cylindrical column or a square steel pipe, as shown in FIG. In this case, since the rib plate 54 cannot be arranged like the column base 50 using H-shaped steel, the protrusion 154 is provided on the side surface of the column base 150 to receive the load in the pushing direction applied to the column base 150. . In the column base 150, four protrusions 154 are provided on the side surface of the column base 150 at positions between the support member 52 and the protrusion 53 at the lower end. The form of the protrusions 154 is not limited to the form shown in FIG. 8, and the number and shape of the protrusions 154 can be changed as appropriate.

FIG. 9 is a perspective view of a column base 250 that is a modification of the column base 50 of the column base fixing structure 100 according to the first embodiment. The support member 52 of the column base 50 used in the column base fixing structure 100 may be a support member 152 having a T-shaped cross section as shown in FIG. 9, for example.

Embodiment 2.
Next, a column base fixing structure 200 according to a second embodiment will be explained. A column pedestal fixing structure 200 according to the second embodiment uses a paper void tube 210 instead of the formwork 10 of the column pedestal fixing structure 100 according to the first embodiment. In the second embodiment, changes to the first embodiment will be mainly described. Regarding each part of the column pedestal fixing structure 200 according to the second embodiment, those having the same functions in each drawing are indicated with the same reference numerals as in the drawings used in the description of the first embodiment.

FIG. 10 is a sectional view of a column base fixing structure 200 according to the second embodiment. FIG. 11 is a sectional view showing a state before the column base 250 of the column base fixing structure 200 according to the second embodiment is installed. The hole 60 formed in the foundation 90 of the column base fixing structure 200 may be formed by a paper void tube 210. The paper void tube 210 is fixed within the foundation formwork 94 prior to the foundation pouring process. The opening on the bottom side of the cylindrical paper void tube 210 is closed so that the filler 91 forming the foundation 90 does not enter into the hole 60.

The paper void tube 210 is removed at least before the injection step in which the filler material is injected into the hole 60. This is called a removal process. Furthermore, an adhesive may be applied to the inner wall surface of the hole 60 after the removal process is completed and before the injection process is started. This increases the bonding force between the filler 95 filled into the hole 60 in the injection process and the filler 91 cast in the foundation placement process.

(Function of column base fixing structure 200)
According to the column base fixing structure 200 according to the second embodiment, the filler 95 is injected after the paper void tube 210, which is a formwork for forming the hole 60, is removed. The contact area between the material 95 and the filler 91 cast in the foundation casting process increases, improving the bonding strength. Further, there is an advantage that the column base fixing structure 200 can be made into a simple configuration. Note that the paper void tube 210 used as a mold for forming the hole 60 may be made of other materials such as resin, metal, etc., as long as it can be removed before the injection step.

Embodiment 3.
Next, a column base fixing structure 300 according to Embodiment 3 will be described. The column base fixing structure 300 according to the third embodiment is obtained by adding a reinforcing steel structure 40 around the formwork 10 of the column base fixing structure 100 according to the first embodiment. In the third embodiment, changes to the first embodiment will be mainly described. Regarding each part of the column base fixing structure 300 according to the third embodiment, those having the same function in each drawing are designated with the same reference numerals as in the drawings used in the description of the first embodiment.

FIG. 12 is a top view of the column base fixing structure 300 according to the third embodiment. FIG. 13 is a cross-sectional view of a column base fixing structure 300 according to the third embodiment. The column base fixing structure 300 includes a reinforcing steel structure 40 surrounding the side surface 62 of the formwork 10 embedded inside the foundation 390. The reinforcing steel structure 40 includes main reinforcements 41 extending vertically on the sides of the formwork 10 and hoop reinforcements 42 arranged horizontally on the sides of the formwork 10. The main reinforcement 41 and the hoop reinforcement 42 are arranged so as to intersect with each other, and their intersections are joined by a joining means such as a binding wire. The main reinforcement 41 is arranged along the side surface 62 of the formwork 10, and is arranged in a rectangular shape when viewed from above. In the foundation 390, the foundation upper part 390b has a filler 91 with at least the minimum required covering thickness around the reinforcing steel structure 40, but compared to the foundation 90 of the first embodiment, most of the foundation upper part 390b has been removed. has been done. The upper part of the foundation 390b has a so-called column shape. Since the column base fixing structure 300 has a small base upper part 390b, structures can be placed around it. In addition, the column base fixing structure 300 can suppress the amount of filler 91 that constitutes the foundation 390, and the cost can be suppressed while ensuring strength.

As shown in FIG. 13, the main reinforcement 41 is formed in a U-shape, with vertically extending portions disposed along two opposing side surfaces 62 of the formwork 10, and horizontally extending portions extending along the bottom surface 62 of the formwork 10. is located along. Note that the main reinforcement 41 is not limited to a U-shape, but may be formed, for example, in an L-shape, and arranged so that the lower end of the main reinforcement 41 protrudes outward.

The column base fixing structure 300 includes an upper reinforcing bar 380 above the bottom reinforcing bar 80 arranged along the upper surface of the sacrificial concrete 92. The upper reinforcing bars 380 are constructed by combining reinforcing bars in a lattice like the bottom reinforcing bars 80, but some of the reinforcing bars are removed so that the formwork 10 and reinforcing bar structure 40 can be placed in the central part. The area where the central reinforcing bars of the upper reinforcing bars 380 have been removed has a rectangular shape along the outer periphery of the formwork 10 and the reinforcing bar structure 40. The upper reinforcing bar 380 is arranged inside the lower foundation 390a, which has a large external shape when viewed from above. The upper reinforcing bars 380 are installed depending on the strength required for the foundation 390. Therefore, depending on the required strength, the column base fixing structure 300 may not include the upper reinforcing bars 380. The bottom reinforcing bars 80 and the top reinforcing bars 380 may be comprised of bellows reinforcing bars. Since it is constructed from bellows reinforcing bars, it can be constructed without the need for a specially skilled reinforcing bar worker.

Furthermore, the reinforcing steel structure 40 is assembled outside of a work site such as a factory. Therefore, the reinforcing steel structure 40 can also be constructed without requiring a specially skilled reinforcing bar worker.

As shown in FIG. 12, the lower foundation 390a and the upper foundation 390b of the foundation 390 are formed in a cylindrical shape in plan view, but are not limited to the cylindrical shape. The foundation 390 is formed by filling concrete as a filler 91 inside foundation forms 394a and 394b (see FIG. 14) that are placed on top of the sacrificial concrete 92 to form the foundation. The shape of the foundation 390 can also take other shapes, such as a square prism shape, depending on the foundation formwork 394.

FIG. 14 is a perspective view of the column base fixing structure 300 according to the third embodiment before a foundation 390 is formed. In the column base fixing structure 300 according to the third embodiment, the formwork 10 is fixed on the sacrificial concrete 92 like the column base fixing structure 100 according to the first embodiment, the bottom reinforcing bars 80 are arranged, and the formwork A reinforcing steel structure 40 is arranged around the 10 . The reinforcing steel structure 40 may be integrated with the formwork 10 at another location, such as a factory, before the formwork 10 is placed on the sacrificial concrete 92. Further, the reinforcing steel structure 40 may be installed around the formwork 10 on the sacrificial concrete 92. The process of installing the reinforcing steel structure 40 around the formwork 10 is referred to as a reinforcing steel structure installation process. The reinforcing steel structure installation step can be performed before the formwork installation step of discarding the formwork 10 and installing it on the concrete 92. Note that the reinforcing steel structure installation process may be performed after the formwork installation process. In this case, a pre-assembled reinforcing steel structure 40 is placed around the formwork 10, or the reinforcing steel structure 40 is constructed around the formwork 10. In the latter case, a specially skilled reinforcing bar worker is required during the reinforcing steel structure installation process.

An upper reinforcing bar 380 is installed above the bottom reinforcing bar 80. Note that in FIG. 14, the bottom reinforcing bars 80 are not shown. The upper reinforcing bars 380 are arranged to cover the formwork 10 and the reinforcing steel structure 40 from above after the formwork 10 and the reinforcing steel structure 40 are installed on the concrete 92. That is, the upper reinforcing bar 380 is arranged so that the formwork 10 and the reinforcing reinforcing bar structure 40 are passed through the hollow part 381 in the center of the upper reinforcing bar 380. The upper reinforcing bar 380 is placed near the upper surface 393a of the lower foundation 390a with a predetermined cover thickness by means of a support member (not shown). Note that the upper reinforcing bars 380 may be omitted depending on the strength required for the foundation 390.

After the formwork 10, reinforcing steel structure 40, bottom reinforcing bars 80, and top reinforcing bars 380 are installed, the foundation formwork 394a is placed around them. The foundation formwork 394a is for forming a foundation lower part 390a that is formed directly above the sacrificial concrete 92 at the bottom of the column base fixing structure 300. The basic formwork 394a is a cylindrical formwork similar to the basic formwork 94 in Embodiment 1, but is low in height and reaches the lower part of the partition member 20 of the formwork 10. There is. Note that the basic formwork 394a is not limited to a cylindrical formwork, but may be a rectangular formwork as shown in FIG. 7B. In the case of a rectangular foundation formwork, a structure is required to support the foundation formwork from the outside, but in the case of a cylindrical foundation formwork using thin steel plates such as the foundation formworks 94 and 394a, it is necessary to maintain the shape. The restraining material 96 makes it possible to maintain the shape even when the filler 91 is poured into the base forms 94 and 394a. The steel plates forming the cylindrical bodies of the base forms 94, 394a, and 394b have a thickness of, for example, 0.6 mm. Further, the height of the foundation formwork 394a from the sacrificial concrete 92 is not limited to only the height shown in FIG. 13, but can be changed as appropriate. The foundation formwork 394a may be referred to as a first foundation formwork.

A plurality of restraining members 96 may be installed in the foundation forms 94 and 394a. A portion where the plurality of restraint members 96 are connected to the base forms 94 and 394a is defined as a fixed portion 97. The plurality of fixed parts 97 are arranged so that the center of gravity of a virtual polygon formed by connecting adjacent fixed parts 97 with virtual lines is located at the center of the cylindrical body formed by the base forms 94 and 394a. It is located. Thereby, the restraining material 96 can maintain the shape of the base formworks 94 and 394a even in a state filled with the filler material 91.

The foundation formwork 394b is placed above the upper reinforcing bars 380. The base formwork 394b is also formed in a cylindrical shape like the base formwork 394a. As shown in FIG. 14, the basic formwork 394b is fixed to a restraining member 396 extending outward from the upper surface of the formwork 10, that is, toward the sides of the formwork 10. The restraining material 396 is fixed to the upper surface of the formwork 10, and is fixed so as to protrude outward from each of the four sides of the upper frame member 12, which is formed in a rectangular shape when viewed from above. Note that the restraining material 396 can also take a form other than that shown in FIG. 14 as long as it is supported by the formwork 10 and can fix the basic formwork 394b. The foundation formwork 394b may be referred to as a second foundation formwork.

The base formwork 394b is fixed to the tip of the upper frame member 12, that is, to the end opposite to the end fixed to the upper frame member 12. As shown in FIG. 14, the upper end of the foundation formwork 394 is provided with fixing portions 397 at four locations and is fixed to restraining members 396. The restraining material 396 restrains the upper end portion of the cylindrical base form 394b at four locations, maintains the shape of the base form 394b, and determines the position of the base form 394b with respect to the form 10.

As described above, with the foundation forms 394a and 394b installed, the filling material 91 is first filled inside the foundation form 394a located at the lower part. With the filler 91 filled inside the base formwork 394a, the filler 91 is cured until it solidifies to some extent. This process is called the first foundation pouring process. When the filling material 91 filled inside the basic formwork 394a is solidified to the extent that it does not flow, the filling material 91 is filled into the basic formwork 394b located at the upper part. This process is called the second foundation pouring process. The foundation formwork 394b according to the third embodiment is fixed by the restraining material 396 that is fixed to the formwork 10 and can maintain the shape of the foundation formwork 394b, so there is no need for an external support structure. Therefore, the first foundation casting step can be carried out even if the foundation lower part 390a formed by the lower foundation formwork 394a is not solidified as described above. That is, the foundation formwork 394b can be filled with the filler 91 to form the foundation upper part 390b once the foundation lower part 390a is in a state where it does not flow. Therefore, according to the foundation formwork 394b according to the third embodiment, it is possible to shorten the time from when the foundation lower part 390a is started to when the foundation upper part 390b is started, and the time required to form the foundation 390 can be shortened. Can be done. In addition, the foundation formwork 394a and the foundation formwork 394b are made of relatively thin steel plates, and as mentioned above, there is no need to install supporting members on the outside, which is twice as necessary as with conventional wooden formwork. . Thereby, the foundation forms 394a and 395b can be buried back into the ground together with the foundation 390, using the foundation forms 394a and 395b as abandoned formwork. That is, by using the foundation formwork 394a and the foundation formwork 394b, it becomes unnecessary to dismantle the formwork before backfilling the foundation 390, which is required when wooden formwork is used. Thereby, the construction period of the foundation 390 can be shortened.

When the above-mentioned foundation pouring process, that is, the first foundation pouring process and the second foundation pouring process, is completed, a hole 60 having a rectangular opening is formed in the upper surface 393b of the foundation 390. After that, similarly to Embodiment 1, an anchor bolt installation process, a pillar erection process, and an injection process are performed.

According to the column base fixing structure 300 according to the third embodiment, the amount of filler 91 forming the foundation 390 is reduced, cost is reduced, and space saving in the region 398 of the foundation 390 can be realized. Therefore, the column base fixing structure 300 has the advantage that other structures can be placed around it. Furthermore, although the foundation 390 has a stepped shape like the lower foundation 390a and the upper foundation 390b, it can be formed in a short period of time using the foundation forms 394a and 394b with a simple structure.

Although the present invention has been described above based on the embodiments, the present invention is not limited only to the configuration of the embodiments described above. For example, the shape of the formwork 10 and the paper void tube 210 in plan view can be changed not only to a rectangle but also to other shapes such as a circle. Further, the structure of the structural member 11 of the formwork 10 is not limited to the shapes shown in FIGS. 4 to 6, and can be changed as appropriate by using materials such as plates or bars. Further, the techniques disclosed in each embodiment can be used in combination. In short, we would like to remind you that the gist (technical scope) of the present invention includes various modifications, applications, and uses that may be made by those skilled in the art as needed.

10 Formwork, 11 Structural member, 12 Upper frame member, 13 Fixing member, 14 Leg member, 15 Lower frame member, 16 Vertical support member, 17 Lateral support member, 20 Partition member, 40 Reinforcement bar structure, 41 Main bar, 42 Hoop muscle, 50 column base, 51 lower end, 52 support member, 52a through hole, 53 protrusion, 54 rib plate, 56 web, 56a surface, 57 flange, 57a tip, 57b inner surface, 60 hole, 61 gap, 62 side, 63 bottom, 80 bottom reinforcement, 81 anchor bolt, 82 nut, 85 nut, 86 nut, 90 foundation, 91 filler, 92 waste concrete, 93 top, 94 foundation formwork, 95 filler, 96 restraint, 97 Fixed part, 100 Column base fixing structure, 150 Column base, 152 Support member, 154 Projection part, 200 Column base fixing structure, 210 Paper void tube, 250 Column base, 300 Column base fixing structure, 380 Upper reinforcing bar, 381 Hollow out Part, 390 foundation, 390a foundation lower part, 390b foundation upper part, 391a foundation lower part, 393a upper surface, 393b upper surface, 394 foundation formwork, 394a foundation formwork, 394b foundation formwork, 396 restraining material, 397 fixed part, 398 area.

Claims (20)

A formwork surrounding the lower end of the column base;
A foundation poured around the formwork,
a reinforcing steel structure surrounding the sides of the formwork;
A foundation formwork that surrounds the formwork and the side of the reinforcing steel structure,
The formwork is
a partition member that has a hole that communicates between the inside and outside of the formwork and surrounds the side of the lower end of the column base;
a structural member that supports the partition member;
A filler is filled in the gap between the lower end of the column base and the formwork,
The foundation formwork includes a first foundation formwork installed on the surface of sacrificial concrete,
The first foundation formwork is a column base fixing structure formed in a cylindrical shape using a steel plate . The foundation formwork further includes a second foundation formwork installed above the first foundation formwork and surrounding a narrower area than the first foundation formwork,
The column base fixing structure according to claim 1, wherein the second foundation formwork is formed into a cylindrical shape using a steel plate. The column base fixing structure according to claim 2, wherein the second foundation formwork is fixed by a restraining member supported by the formwork. The reinforcing steel structure is
A main reinforcement extending in the vertical direction on the side of the formwork;
The column base fixing structure according to any one of claims 1 to 3 , further comprising a hoop bar horizontally arranged on a side of the formwork. The partition member is
The column base fixing structure according to any one of claims 1 to 4, comprising a mesh structure. The partition member is
The column base fixing structure according to any one of claims 1 to 5 , which is made of metal lath. The column base is
a support member projecting laterally above the upper surface of the foundation;
The support member is
The column base fixing structure according to any one of claims 1 to 6 , which is connected to the foundation. The basis is
comprising anchor bolts installed around the formwork,
The support member is
The column base fixing structure according to claim 7 , which is connected to the foundation via the anchor bolt. The column base is
The column base fixing structure according to any one of claims 1 to 8 , which is made of H-beam steel having flanges formed at both ends of the web. The column base is
A plate-like rib plate provided below the upper surface of the foundation,
The rib plate is
The column pedestal fixing structure according to claim 9 , wherein the column pedestal fixing structure is installed with a plate surface facing the direction in which the column pedestal is erected. The column base is
The column base fixing structure according to any one of claims 1 to 8, which is a cylindrical body. The column base is
The column pedestal fixing structure according to any one of claims 9 to 11 , comprising a protrusion on the side surface. The protruding portion is
The column base fixing structure according to claim 12 , which is formed below the upper surface of the foundation. A building comprising the column base fixing structure according to any one of claims 1 to 13 . a formwork installation step of installing a formwork comprising a partition member having a hole that communicates the inside and outside of the enclosed space and a structural member that supports the partition member;
A reinforcing reinforcing bar structure installation step of installing a reinforcing reinforcing bar structure including main bars extending in the vertical direction and hoop reinforcing bars extending in the horizontal direction and surrounding the formwork on the side of the form;
a foundation formwork installation step of installing a foundation formwork that surrounds the sides of the formwork and the reinforcing steel structure;
a foundation pouring step of pouring a foundation around the formwork;
a pillar-erecting step of inserting and erecting a pillar base inside the form;
an injection step of injecting a filler into the gap between the formwork and the column base ,
The foundation formwork includes a first foundation formwork installed on the surface of sacrificial concrete,
The first foundation formwork is formed into a cylindrical shape using a steel plate,
The method for constructing a column base fixed structure, wherein the foundation pouring step includes a first foundation pouring step of pouring the foundation into the first foundation formwork. The foundation formwork further includes a second foundation formwork installed above the first foundation formwork and surrounding a narrower area than the first foundation formwork,
The second foundation formwork is formed into a cylindrical shape using a steel plate,
Construction of the column base fixing structure according to claim 15, wherein the foundation pouring step further includes a second foundation pouring step of pouring the foundation into the second foundation formwork after the first foundation pouring step. Method. 17. The method for constructing a column base fixing structure according to claim 16, wherein the second foundation formwork is fixed by a restraining member supported by the formwork. The method for constructing a column base fixing structure according to any one of claims 15 to 17 , comprising an anchor bolt installation step of installing an anchor bolt on the upper surface of the foundation. The method for constructing a column pedestal fixing structure according to claim 18 , wherein a flange portion formed to protrude laterally from the column pedestal and the anchor bolt are connected. Before the injection step, a nut is attached to the anchor bolt, the flange is placed on the nut, and the position of the nut is adjusted to adjust the position of the column base in the height direction. The method for constructing a column base fixing structure according to claim 19 , comprising a column base position adjustment step.

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