JP2000170171A - Column bottom member and structural foundation using the member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new column bottom member and a structural foundation using the member by which the proof stress can be enhanced, members and man-days can be reduced, strength calculation can be easily done, and concrete is prevented from rupture in a part where stresses are absorbed. SOLUTION: This column bottom member 10 is provided with a rectangular column-joint part 10a and a wide part 10b, and lug-sticking parts 10c. The lug-sticking parts 10c are stuck to a corner or two adjacent corners of the column-joint part 10a, and the wide part 10b is formed to connect the other ends of the side where the lug-sticking part 10c is positioned and is formed into a flange protruded outward. In this way, since the wide part 10b is extended to the whole area where an underground beam 11 is not connected, a stress at applying force can be dispersively absorbed and hence, the concrete 8 is prevented from rupture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foundation of a building such as a steel framed house, and more particularly to a stress applied to a beam in an upper building, a gusset plate and a rib provided at a connection portion of a column and a beam, or an underground beam. The present invention relates to a column bottom member capable of reducing the above-mentioned, and a foundation for construction using the same.

[0002]

BACKGROUND OF THE INVENTION In a column-beam connection of a building having a building foundation using a section steel as a strength member, a range in which distortion of an underground beam 11 'occurs when a bending moment (stress F) is applied to a column. The (effective bending length) extends to a point about six times the diameter D of the column 3c 'at the time of the positive force as shown in FIG. 7A, while being negative as shown in FIG. 7B. When a force is applied, it reaches a point about three times the diameter D of the pillar. For this reason, in order to maintain the strength of the building, it is desirable to use a continuous foundation type in which the underground beam 11 'is provided over the entire area within the roots, and members and man-hours for this are essential.

[0003] The applicant of the present invention has made an effort to improve the proof strength by improving the construction base using a section steel as the strength member, to reduce the number of members and man-hours, and to further facilitate the strength calculation. The present inventors have invented the “Strength Improvement Structure in Construction Foundation”, and have already filed an application as Japanese Patent Application No. 9-350113. According to the present invention, by providing a bracket beam so as to form a cross shape with an underground beam, the effective bending length of the underground beam at the time of load is shortened by the bracket beam, thereby enabling construction with an independent foundation type. It was that. However, in the course of further research and development, it was attempted experimentally to apply a load that far exceeded the normal assumed load. In some cases, the concrete above the bracket beam was broken.

[0004]

[Technical problem to be developed] The present invention has been made in view of such a background, and aims to improve the proof stress, reduce the number of members and man-hours, and further facilitate the strength calculation. It is an object of the present invention to develop a new column bottom member that does not cause concrete breakage in a portion that absorbs stress and that does not cause concrete breakage, and a construction foundation using the same.

[0005]

According to a first aspect of the present invention, there is provided a pillar bottom member which is a plate-like member located at the lowermost part of a pillar of a foundation for construction, wherein the plate-like member has a rectangular pillar connection portion, A wide portion and a lug portion integrally formed with the pillar connection portion, and the lug portion protrudes from one corner portion or two adjacent corner portions of the pillar connection portion. The wide portion is formed in a flange shape protruding outside the pillar connection portion so as to connect the other end of the side where the lug portion is located. According to the present invention, the column is connected to the column connecting portion of the column bottom member,
By connecting the underground beam to the side surface of this pillar, the foundation structure can be easily configured. In addition, since the connection of the underground beam to the pillar can be performed without complicating the shape of the underground beam, the man-hour required for the processing can be reduced, and the strength calculation can be easily performed. be able to. Furthermore, since the wide portion extends all over the unconnected portion of the underground beam, the stress at the time of load can be dispersed and absorbed, and the concrete does not break.

The column bottom member according to claim 2 is characterized in that, in addition to the above requirements, a hole for flowing down concrete is formed in the wide portion. ADVANTAGE OF THE INVENTION According to this invention, obstruction of the concrete flowing down by a wide part can be prevented, and concrete can be poured uniformly in a root room.

The foundation structure using the column bottom member according to claim 3 forms the foundation structure by combining a column with an underground beam,
Further, in the construction foundation in which the foundation structure is located in the root room and surrounded by concrete within a certain range, the connection portion between the underground beam and the column connects a column bottom member to a lower end portion of the column, and a lower portion of the column. An underground beam is connected to the side surface, and the wide portion of the column bottom member is located on an extension of the underground beam. ADVANTAGE OF THE INVENTION According to this invention, especially the effective bending length at the time of a positive load can be shortened, and intensity | strength can be maintained even if the length of the underground beam inside a foundation structure is shortened.
In addition, particularly at the time of a negative load, the stress applied to the wide portion of the column bottom member is dispersed and absorbed, so that the concrete outside the foundation structure is not broken.

According to a fourth aspect of the present invention, there is provided a foundation structure using a column bottom member, wherein the foundation structure is constructed by combining an underground beam with a supporting box, and furthermore, the foundation structure is positioned within a root room and a certain range of concrete is provided. In the construction foundation surrounded by, the connecting portion between the underground beam and the support box connects the column bottom member to the lower end of the support box, and connects the underground beam to the side surface of the support box. The wide portion of the pillar bottom member is located on the extension of the underground beam. ADVANTAGE OF THE INVENTION According to this invention, especially the effective bending length at the time of a positive load can be shortened, and intensity | strength can be maintained even if the length of the underground beam inside a foundation structure is shortened. In addition, particularly at the time of a negative load, the stress applied to the wide portion of the column bottom member is dispersed and absorbed, so that the concrete outside the foundation structure is not broken.

[0009] Further, a foundation structure using the column bottom member according to the fifth aspect has the following features in addition to the requirements according to the third or fourth aspect.
The root margin in which the foundation structure is buried is characterized in that the location where the column bottom member is located is dug more extensively than the portion where the underground beam is located. According to the present invention, since the gravity of the concrete acts on the wide portion of the pillar bottom member over a wide range, the stress applied to the wide portion is absorbed, and the concrete outside the foundation structure is not broken. The above object is achieved by using the configuration of the invention described in each of the claims.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be specifically described based on the illustrated embodiments. FIG. 1 shows the overall shape including a building foundation 1 and a foundation structure 1A and a building 2 and the like related thereto.
The column structure 3 and the like are supported at appropriate locations to form the basic structure 1A. And, as shown in FIGS. 3 and 4, the base ground 5 excavated the reference ground plane GL at the construction site.
The bottom of the root 5 is formed by pressing the split stone 6 with a rammer or the like as appropriate, and further throwing concrete 7 or the like thereon.

There are two types of configurations of the column unit 3, one type of which connects the underground beam 11 to the column 3 c erected on the discarded concrete 7, and the other type. Is a type in which a support box 29 is provided at a place where the column 3c is installed, and the underground beam 11 is connected to the support box 29. First, the configuration of the former type column unit 3 is shown in FIG.
As shown in FIG. 1, a column bottom member 10 described below is welded to the lower end of a column 3c to which a square steel pipe is applied as an example. The configuration of the latter type column unit 3 is formed by welding a column bottom member 10 described below to a lower end portion of a support box 29 to which a square steel pipe is applied as an example, as shown in FIG.

As shown in FIG. 2, the column bottom member 10 has a column connecting portion 10a having a rectangular shape larger than the cross section of the column 3c or the supporting box 29, and a side of the column connecting portion 10a. And a wide portion 10b and a lug portion 10c integrally formed. The lugs 10c project from one corner or two adjacent corners of the pillar connection part 10a, and FIG. On the other hand, the lugs 10c are in a state of protruding, and FIG. 2B is a state in which the lugs 10c are protruding from two adjacent corners. The wide portion 10b is formed in a flange shape protruding outside the pillar connection portion 10a so as to connect the other end of the side where the lug portion 10c is located. Further, a hole 10d for flowing down the concrete is formed at an appropriate place in the wide portion 10b. Further, a bolt hole 10e is formed in the wide portion 10b and the lug portion 10c with the same relative position as a bolt hole 20a provided in the anchor bolt plate 20 or the support box 29 described later.

Next, the base plate 3a which is a component of the column unit 3 using the support box 29 will be described. This is a plate-like member formed by processing a steel plate into a rectangular shape larger than the cross-sectional shape of the column 3c. The relative positions of the base plate 3a and the anchor bolt plate 20 and the load-bearing plate 28 described later are the same. The bolt hole 3b and the bolt hole 20a are respectively formed.

Next, the foundation 1 for construction provided in the root 5
The strength members are described in more detail. First, code 1
A is a foundation structure which is a main strength member of the construction foundation 1, which is formed by combining a steel underground beam 11 in an appropriate plane frame shape or further combining this with a column 3c. . The basic configuration of the underground beam 11 is, for example, an H-section steel, an I-section steel, or the like, and includes an upper flange 11a, a lower flange 11b, and a web 11c provided orthogonally between the two. Consists of

The upper flange 11 of the underground beam 11
a and the lower flange 11b at appropriate locations.
1d is drilled. The underground beam 11 is, for example, manufactured in a factory with the lower rebar 12 welded in advance. .
Further, an upper reinforcing bar 13 is provided on the upper flange 11a. In this case, a reinforcing bar previously combined in a girder shape is placed above the underground beam 11 in a state where the underground beam 11 is installed in the root room 5, and an appropriate location is provided. Is welded to the upper flange 11a of the underground beam 11. Thus, the upper reinforcing bar 13 and the lower reinforcing bar 12
Is welded to the underground beam 11 to be integrated, and significantly contributes to strength improvement as compared with the stirrup used in the conventional method (RC method or the like). Further, the upper reinforcing bar 13 and the lower reinforcing bar 12 may be separately connected by a reinforcing bar or the like. In this case, the strength can be further improved.

The underground beam 11 is provided with a spacer 14 on the lower surface of a lower flange 11b. For example, the spacer 14 is composed of a fixed spacer 14a obtained by welding a rectangular tubular member as shown in FIG. The applied adjustable spacer 14b is used. Of course everything is adjustable spacer 14b
Or only the fixed spacer 14a. In addition, the fixed spacer 14a is to obtain a temporary dimension to the last, and the fixed spacer 14a is required for accurate setting.
An adjustable spacer 14b may be provided adjacent to each a.

When connecting the underground beams 11 in the longitudinal direction, a bolt hole 11d is formed in the web 11c, a splice 16 is applied to the hole 11d, and the web 11c is fixed by a bolt nut 17 so as to be continuous. The foundation structure 1A is constituted by combining the underground beam 11 or the pillar 3c with the underground beam 11 in this way. In this combination, the rigid connection state is increased by increasing the number of the bolt nuts 17 and the like. Is preferable. Further, the splice 16 can have a stronger rigid connection by increasing the length dimension and increasing the number of bolt holes 11d and the number of bolt nuts 17.

In order to fix the column unit 3 on the discarded concrete 7, an anchor bolt plate 20 obtained by processing a steel plate into a rectangular shape as shown in FIG. 5 is used. This anchor bolt plate 20 has bolt holes 20
a is drilled, and anchor bolts 21 and the like are attached thereto.

Further, a level adjuster 22 is used as a member for supporting the column unit 3. This is disclosed in Japanese Patent Application Laid-Open No. Hei 8-209712 "Level Adjuster" by the present applicant. As shown in FIG. 4, a movable cup 24 is screwed into a cylindrical fixed cup 23 in a nested manner. The height can be freely adjusted by adjusting the screwing. The supporting box 29 provided at the place where the column 3c is installed is, for example, a square steel pipe applied. As shown in FIG. The bottom member 10 is welded.

The members constituting the foundation 1 for construction of the present invention and the column bottom member 10 are as described above. Hereinafter, a basic structure 1A constituted by different combinations of these members will be described. .

(1) Foundation Structure Composed of Underground Beam Connected to Pillar Standing on Discarded Concrete First, underground beam 11 is connected to pillar unit 3 standing up on discarded concrete 7. The basic structure 1A will be described. This configuration is disclosed in Japanese Patent Application Laid-Open No.
No. 1463, entitled "Column-integrated Column Base Fixed Foundation Structure and Its Construction Method". Specifically, FIG.
As shown in FIGS. 4 and 5, an anchor bolt 21 and a level adjuster 22 are provided so as to protrude from the surface of the discarded concrete 7 cast in the root 5. Next, the column unit 3 configured by welding the column bottom member 10 to the lower end of the column 3c is
It is placed on the level adjuster 22 protruding from the discarded concrete 7 and fixed to the anchor bolt 21, and the underground beam 11 is connected to the lower side surface of the column 3c and fixed by welding or the like. The anchor bolt 21 and the level adjuster 22
May be placed and fixed on the discarded concrete 7 after casting.

Therefore, in the portion where the underground beam 11 connected from two directions as shown in FIG.
A column bottom member 10 shown in (a) is used,
As shown in FIG. 5, the wide portion 10b of the pillar bottom member 10 is located on the extension of the underground beam 11 welded to two orthogonal surfaces of the pillar 3c. Thereafter, concrete 8 is poured into the root room 5 to form the foundation 1 for construction. At this time, since the hole 10 d is formed in the wide portion 10 b of the pillar bottom member 10, the concrete 8 flows downward from the hole 10 d and spreads evenly in the root room 5.

(2) A basic structure in which a support box is provided at the place where the pillar is installed, and an underground beam is connected to the support box. Next, a support box 29 is provided at the place where the pillar 3c is installed. Basic structure 1A constructed by connecting underground beam 11 to box 29
Will be described. This configuration is disclosed in Japanese Patent Application Laid-Open No. 9-264029 by the applicant of the present invention, "Construction foundation, foundation structure using the same, and construction method thereof". As shown in FIG. A support box 29 using a square steel pipe is provided at the installation location of 3c. A column bottom member 10 is fixed to a lower portion of the support box 29 by welding or the like, and a rectangular load-bearing plate 28 is fixed to an upper portion thereof.
2 fixed.

In the portion where the underground beam 11 connected from two directions as shown in FIG.
A column bottom member 10 shown in (b) is used,
The underground beam 11 is attached to two opposing side surfaces of the support box 29.
Web 11c, upper flange 11a and lower flange 11
b is fixed by welding or the like, and the underground beam 11 is fixed to the surface of the support box 29 inside the basic structure 1A. Part 1
0b will be located.

The bearing plate 28 is connected to the connecting bolt 29a.
And the column bottom member 10, and the connecting bolt 29a is projected above the load-bearing plate 28. Then, the concrete 8 is poured into the root 5 so that the connecting bolt 29a and the level adjuster 22 protrude from the surface of the concrete 8, and the base plate 3a is welded to the lower end of the column 3c. The unit 3 is placed and fixed on the level adjuster 22.

Also, as shown in FIG. 1, the underground beam 11 is constructed so that the foundation structure 1A is of an independent foundation type. In other words, the underground beam 11 connected to the adjacent column unit 3 is continued in one direction at the column-beam connection portion on the outer peripheral portion of the basic structure 1A. That is, the underground beam 11 is made independent.

[0027]

According to the present invention, the strength can be improved, the number of members and man-hours can be reduced, the strength can be easily calculated, and the concrete 8 can be broken at the portion where the stress is absorbed. It is possible to provide a new pillar bottom member that does not cause a rise and a foundation for construction using the same.

[Brief description of the drawings]

FIG. 1 is a partially enlarged plan view showing strength members of an entire building including a foundation for construction according to the present invention.

FIG. 2 is a plan view showing a column bottom member of the present invention.

FIG. 3 is a vertical sectional side view showing the vicinity of a beam-column joint of a foundation for construction.

FIG. 4 is an enlarged longitudinal side view showing the vicinity of a beam-column joint of a foundation for construction.

FIG. 5 is a perspective view showing an embodiment in which an underground beam is connected to a column erected on abandoned concrete at a corner of a foundation for construction.

FIG. 6 is a perspective view showing a mode in which an underground beam is connected to a support box provided on abandoned concrete at a T-shaped portion of the foundation for construction.

FIG. 7 is an explanatory diagram showing stress on a building and how the stress is dispersed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Construction foundation 1A Foundation structure 2 Building 3 Pillar unit 3a Base plate 3b Bolt hole 3c Pillar 5 Root room 6 Split chestnut stone 7 Discarded concrete 8 Concrete 10 Pillar bottom member 10a Pillar connection part 10b Wide part 10c Protruding part 10d hole 10e bolt Hole 11 Underground beam 11a Upper flange 11b Lower flange 11c Web 11d Bolt hole 12 Lower rebar 13 Upper rebar 14 Spacer 14a Fixed spacer 14b Adjustable spacer 16 Splice 17 Bolt nut 20 Anchor bolt plate 20a Bolt hole 21 Anchor bolt 22 Level adjuster 23 Fixed cup 24 Movable cup 28 Strength plate 29 Support box 29a Connecting bolt D diameter F Stress GL Reference ground surface

Claims (5)

[Claims] 1. A plate-like member located at the lowermost part of a pillar of a foundation for construction, the plate-like member has a rectangular pillar connection part, a wide part and an ear formed integrally with the pillar connection part. And a lug portion, wherein the lug portion projects from one corner or two adjacent corners of the pillar connection portion, and the wide portion has a position where the lug portion is located. A column bottom member formed in a flange shape protruding outside the column connecting portion so as to connect the other ends of the sides to be formed. 2. The pillar bottom member according to claim 1, wherein a hole for flowing concrete is formed in the wide portion. 3. A construction foundation in which an underground beam is combined with a pillar to form a foundation structure, and furthermore, the foundation structure is located in a root room and is surrounded by concrete within a certain range. The connecting part connects the pillar bottom member to the lower end of the pillar,
An underground beam is connected to a lower side surface of a pillar so that a wide portion of the pillar bottom member is located on an extension of the underground beam. 4. A construction foundation in which an underground beam is combined with a support box to form a foundation structure, and furthermore, the foundation structure is located within a root room and is surrounded by concrete within a certain range. The connection portion with the box, the column bottom member is connected to the lower end of the support box, the underground beam is connected to the side surface of the support box, the extension of the underground beam in the column bottom member A foundation for construction using a pillar bottom member, characterized in that a wide portion is located. 5. The root margin where the foundation structure is located is formed by digging a location where the column bottom member is located in a wider area than a location where an underground beam is located. Foundation for construction using column bottom members.