JPH11148136A - Bearing force improvement structure in foundation for construction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure for enhancing bearing force in foundation for new construction wherein the foundation for the construction by using shape steel as strength member of the foundation is further improved, bearing-face improvement is contrived, members and man-hour can be reduced and strength calculation can be made easy. SOLUTION: Underground beams 11 are connected to a column beam connection part from two or three directions, and a bracket beam 31 is provided so that the planar shape is a crossed shape together for the column beam connection part with the underground beams 11. At the time when positive force is applied, effective bending length can be shortened, and strength can be maintained even if the length of the underground beam 11 is made short.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foundation for a building such as a steel framed house, and more particularly to a bracket beam provided at a beam-column connection portion. Accordingly, the present invention relates to a structure for improving the strength of a construction foundation, which can reduce stress applied to a beam in an upper ridge, a gusset plate and a rib or an underground beam provided in a column-beam connection portion.

[0002]

BACKGROUND OF THE INVENTION In a column-beam connection part of a steel-concrete continuous foundation, the range (effective bending length) in which the underground beam is deformed when a bending moment (stress F) is applied to the column is shown in FIG.
As shown in FIG. 1 (a), at the time of the positive load, it reaches a point about six times the diameter D of the column. On the other hand, as shown in FIG. 11 (b), at the time of the negative load, three times the diameter D of the column. Extent. For this reason, in order to maintain the strength of the structure, it is desirable to adopt a continuous foundation type in which the underground beam 11 'is provided over the entire area of the root, and members and man-hours for this are essential.

By the way, the present applicant uses a section steel as a strength member of a foundation, has a good construction efficiency, can accurately set anchor bolts, can keep the height of the foundation low, and has a shallow root cutting dimension. The construction of a construction base that can be carried out by excavation in a narrow range and related members have been devised, and several patent applications and utility model registration applications have been filed (Japanese Patent Application Laid-Open No. 8-41897, Kaihei 8-209712
JP-A-8-209927, JP-A-8-209983
No. 7, Utility Model Registration No. 3024518, JP-A-9-19-1
No. 51463, Japanese Patent Application No. 8-103452, etc.).

[0004]

[Technical Problem Attempted to Develop] The present inventor can further improve the construction foundation using a section steel as a strength member of the foundation, improve the proof stress, reduce the number of members and man-hours, and further improve the strength. The technical task was to develop a structure for improving the strength of a new foundation for construction that can facilitate calculations.

[0005]

According to a first aspect of the present invention, there is provided a structure for improving a proof strength of a foundation for construction, in which an underground beam is combined with an appropriate plane frame or a column is combined with the underground beam to form a foundation structure. Further, in a joint structure of a beam-column connection portion applied to a construction foundation in which the foundation structure is surrounded by a certain range of concrete, an underground beam from two or three directions is connected to the beam-beam connection portion. The beam connecting portion is characterized in that a bracket beam is provided so that its planar shape is cross-shaped with 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 an underground beam is shortened.

[0006] The structure for improving the strength of the construction foundation according to claim 2 is characterized in that, in addition to the above requirements, the foundation structure is an independent foundation type. According to the present invention, members and man-hours can be reduced, and cost can be reduced.

According to a third aspect of the present invention, in addition to the above requirements, the bracket beams or the bracket beams and the underground beams are joined to each other by a striking plate. . According to the present invention, the stress applied to each bracket beam can be dispersed.

[0008] Further, in the fourth aspect of the present invention, in addition to the requirement of the third aspect, a hole for concrete flowing down is provided in the fire plate. ADVANTAGE OF THE INVENTION According to this invention, the block of the concrete flowing down by a striking plate can be prevented, and concrete can be cast evenly in the root.

According to a fifth aspect of the present invention, in addition to the above requirements, the column-beam connection portion is a column unit lower end portion, and a base plate provided at a lower end of the column unit is connected to the column. A lug portion is provided in a portion outside the width dimension of the underground beam to be formed. According to the present invention, since the connection of the underground beam or the bracket beam to the column can be performed without complicating the shape of these members, it is possible to reduce the number of steps required for processing, Strength calculation can be easily performed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be specifically described based on the illustrated embodiments. FIG. 1 shows the entire shape including a foundation 1 for construction, a foundation structure 1A, and a building 2 related thereto, and the foundation 1 for construction is a building 2
The column structure 3 and the like are supported at appropriate locations to form the basic structure 1A. And, as shown in FIGS. 2 and 3, 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 then throwing concrete 7 or the like thereon.

As an example of the configuration of the column unit 3, a base plate 3a obtained by appropriately processing a steel plate is welded to an end of a column 3c to which a square steel pipe is applied. The base plate 3a and an anchor bolt plate 20 described later
In both cases, the bolt holes 3b and the bolt holes 20a are formed in the same relative position.

Next, the foundation 1 for construction provided in the root room 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 foundation 1 for construction, which is formed by combining a steel underground beam 11 in an appropriate plane frame shape, or further adding a pillar 3c.
Are combined. 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 reinforcing bar 12 welded in advance, and the lower reinforcing bar 12 is formed by combining reinforcing bars of, for example, about 12 mm in a cross-girder shape at an appropriate pitch. .
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. The upper rebar 13 and the lower rebar 12
It is welded to the underground beam 11 and integrated, and compared with the stirrup used in the conventional method (RC method, etc.)
This will significantly contribute to strength improvement. In addition, upper rebar 1
The third reinforcing bar 12 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 the lower flange 11b.
Is a fixed spacer 14a obtained by welding a rectangular tubular member as shown in FIG. 3 and an adjustable spacer 14b using a bolt and nut.
And Of course, all may be configured by the adjustable spacer 14b, or may be only the fixed spacer 14a. In addition, the fixed spacers 14a are designed to obtain temporary dimensions, and an adjustable spacer 14b may be provided adjacent to each fixed spacer 14a for accurate setting.

A gusset plate 15 is provided at the end of the portion where the underground beams 11 are connected to each other by being abutted in an orthogonal state, as shown in FIG. The gusset plate 15 is provided between the upper flange 11a and the lower flange 11b so as to project perpendicularly to the web 11c. A bolt hole 15a is formed in a portion of the web 11c on the tip side that overlaps the gusset plate 15.

These are fixed by bolts and nuts 17. Gusset plate 1
When the flange 5 is formed only up to the end face of the flange, as shown in FIG. 4 (b), the splice 16 may be fixed separately. Further, when connecting in the longitudinal direction, a bolt hole 15a is formed in the web 11c as shown in FIG. 4 (c), and a splice 16 is applied thereto and fixed so as to be continuous.

The foundation structure 1A is formed by combining the underground beam 11 or the pillar 3c with the underground beam 11 in this manner. In this combination, the number of the bolt nuts 17 is increased. It is preferable to make a rigid connection state. In addition, the splice 16 can have a stronger rigid connection by increasing the length of the splice 16 and increasing the number of the bolt holes 15a and the number of the bolt nuts 17.

In fixing the column unit 3, an anchor bolt plate 20 made of a steel plate processed into a rectangular shape is used. A bolt hole 20a is formed in the anchor bolt plate 20, and an anchor bolt 21
Etc. are attached.

Further, a level adjuster 22 is used as a member for supporting the column unit 3. This is disclosed in Japanese Unexamined Patent Publication No. Hei 8-209712 "Level Adjustment Body" by the present eyesight person. As shown in FIG. 3, a movable cup 24 is screwed into a cylindrical fixed cup 23 in a nested manner. The movable cup 24 can be adjusted by adjusting the screwing.

The members constituting the basic structure 1A to which the "Strength Improving Structure in Construction Foundation" of the present invention is applied are as described above, and the basic structure constituted by different combinations of these members will be described below. Regarding 1A, an embodiment in which the proof stress improving structure 30 is applied will be described. Prior to this description, the proof stress improving structure 30 will be described. The proof stress improving structure 30 is configured by combining a bracket beam 31 with the basic structure 1A. As shown in FIGS. 5 to 7, this bracket beam 31 is formed by applying an H-beam, an I-beam, or the like as an example, similarly to the underground beam 11, and includes an upper flange 31a, a lower flange 31b, and And a web 31c provided orthogonally between the two. In the type shown in FIGS. 6 and 7, a bolt hole 31d is formed at an appropriate place of the web 31c in the bracket beam 31, specifically, at a place connected to the basic structure 1A. And this bracket beam 31
Is fixed to the basic structure 1A using the gusset plate 15, the splice 16 and the bolt / nut 17 as appropriate, and welded.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (1) Underground structure in which underground beams are connected to columns erected on discarded concrete First, underground beams 11 are connected to column units 3 erected on discarded concrete 7 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. 3 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 room 5, and the column unit 3 is connected to the level adjuster 22.
The underground beam 11 and the bracket beam 31 are connected to the side surface of the column 3c and fixed by welding or the like.

Of course, any one or more or all of the column unit 3, the underground beam 11, the bracket beam 31, the lower reinforcing bar 12, and the upper reinforcing bar 13 may be integrated in a factory in advance and carried to the site. Therefore, in the portion where the underground beam 11 connected from two directions as shown in FIG. 1 becomes a plane angle, as shown in FIG. 5, the underground beam 11 welded to two orthogonal surfaces of the column 3c. And a bracket beam 31 welded to the remaining two surfaces (the outer peripheral side of the building 2), to form a cross-shaped planar shape as defined in claim 1, and to constitute the proof stress improving structure 30. Thereafter, concrete 8 is poured into the root room 5 to form the foundation 1 for construction.

(2) Foundation Structure Connected with Underground Beams Next, the case where the underground beams 11 are connected to form the foundation structure 1A will be described. This configuration is disclosed in Japanese Patent Application Laid-Open No. 8-41897 “Building Foundation and Construction Method” by the present applicant, and as shown in FIG.
1 are connected along the root 5 to form the basic structure 1A.

As shown in FIG. 1, as an example, in a portion where the underground beam 11 connected from three directions becomes a T-shaped plane, the web 11 c of the underground beam 11 or the upper flange 1 is formed.
The web 31c of the bracket beam 31 is abutted against the gusset plate 15 (see FIG. 4B) provided between the lower flange 11a and the lower flange 11b, the splice 16 is applied, and the bolt 31 is fixed. Therefore, as shown in FIG. 6, three underground beams 11 combined in an orthogonal state and a bracket beam 31 combined on an extension of one of the underground beams 11 as defined in claim 1. Structure 30 with improved cross-sectional shape with cross-sectional shape
Is configured. Incidentally, in the case of the independent foundation type described later, the dimension of the underground beam 11 in the perpendicular direction is at least three times, preferably at least six times the diameter D of the column 3c.

The pillar 3c on the upper surface of the basic structure 1A
An anchor bolt plate 20 is fixed to a place where is installed by welding or the like, and an anchor bolt 21 integrally attached thereto is projected upward. Further, a level adjuster 22 is provided on the anchor bolt plate 20. After that, concrete 8 is cast to surround the foundation structure 1A, and the anchoring bolt 21 and the level adjusting body 22 are projected from the surface of the concrete 8 to form the building foundation 1, and the column unit 3 is level-adjusted. After being placed on the body 22, it is fixed.

(3) A basic structure in which a supporting box and a bearing plate are provided at the place where the pillar is installed, and an underground beam is connected to the supporting box. A basic structure 1A in which a plate 28 is provided and the underground beam 11 is connected to the support box 29 will be described. This configuration is disclosed in Japanese Patent Application No. 8-103452 filed 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 is provided at the place where the column 3c is installed.

As an example, in a portion where the underground beam 11 connected from two directions is linear in a plane, the web 1 of the underground beam 11 is opposed to the two opposing surfaces of the support box 29.
1c, the upper flange 11a and the lower flange 11b are fixed by welding or the like. Furthermore, on the other two surfaces of the support box 29,
The web 31c, the upper flange 31a, and the lower flange 31b of the bracket beam 31 are fixed by welding or the like. Therefore, in the straight part of the building 2, as shown in FIG. 7, the underground beam 11 welded to two surfaces of the support box 29 and the bracket beam 31 welded to the remaining two surfaces are claimed. Item 1
As described in the above, the proof stress improving structure 30 is formed with a cross-shaped planar shape.

The upper and lower bearing plates 28 are connected by the connecting bolt 29a, and the connecting bolt 29a is projected upward. Further, the upper load-bearing plate 28 includes
A level adjuster 22 is provided. After that, concrete 8 is poured so as to surround the basic structure 1A, the connecting bolt 29a and the level adjuster 22 are made to protrude from the surface of the concrete 8, and the column unit 3 is moved to the level adjuster 22.
It is placed and fixed on the device.

As described above, the building 2 as shown in FIG.
Between the column 3c and the underground beam 11 (column-beam joint)
(The T-shaped part, the corner part, and the straight part are classified according to the mode of the underground beam 11).

The underground beam 3 constituting the proof stress improving structure 30
1 is a substructure 1 as defined in claim 2 and as shown in FIG.
A is configured to be an independent basic model. 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.

Next, an embodiment using the firing plate 32 defined in claims 3 and 4 will be described.
As shown in FIGS. 8A and 8B, in the T-shaped portion and the straight portion of the underground beam 11 in the building 2, the bracket beam 3 is used.
From the underground beams 11 located on the left and right sides of the base 1, fire plates 32 to which steel plates are appropriately applied are fixed by welding or bolting. At the corner of the underground beam 11 in the building 2 shown in FIG. 8 (c), a fire plate 32 is provided between two bracket beams 31 having an orthogonal positional relationship.
And the fire plate 32 is fixed from the underground beam 11 adjacent to each bracket beam 31.
As described above, the bracket beams 31 or the bracket beams 3
1 and the underground beam 11 are joined to each other by a firing plate 32.

Further, as shown in FIG. 8 (d), a hole 32a is formed in the firing plate 32 so as not to cause a reduction in the overall strength. This hole 3
By providing 2a, the firing plate 32 does not hinder the concrete 8 from flowing down, and the building foundation 1 can be formed densely.

Next, a configuration in the case where the connecting portion of the underground beam 11 defined at claim 4 is the lower end of the column unit 3 will be described. First, a conventional connection mode between the column unit 3 and the underground beam 11 will be described. As shown in FIG. 9A, the end surfaces of the upper flange 11a 'and the web 11c' of the underground beam 11 'are brought into contact with the side surface of the lower end of the column unit 3'. At this time, the lower flange 11b 'is machined so that a part thereof is cut out.
The end face of b 'abuts on the end face of base plate 3a', and the lower surface of web 11c 'exposed by the notch abuts on the upper surface of base plate 3a'. In this state, the contact portion is welded. According to the above-described method, the shape of the welded portion between the underground beam 11 and the column unit 3 is complicated, so that the strength calculation is complicated.

On the other hand, when the connecting portion of the underground beam 11 defined in claim 4 is the lower end of the column unit 3, the configuration shown in FIG.
As shown in (b), the base plate 3a is provided with a lug 3d at a portion outside the width of the underground beam 11 connected to the column 3c. In other words, the four sides of the base plate 3a have substantially the same dimensions slightly longer than the outer periphery of the pillar 3c, and the lugs 3d are provided at the four corners of the base plate 3a. Incidentally, it is preferable that the lug portion 3d is formed by cutting a single plate instead of being post-processed to the base plate 3a in consideration of durability.

Response to Increase in Load (See FIG. 10) The dimensions of the bracket beam 31 described above are naturally set in accordance with the load as a given condition at the design stage. It is preferable to arrange the bracket beams 31 that are standardized in advance and arranged in parallel.

[0036]

According to the present invention, which has the above-described structure, it is possible to improve the proof stress, reduce the number of members and man-hours, and furthermore, to improve the strength calculation. It is possible to provide a structure for improving the proof stress. Further, as shown in FIGS. 11 (c) and 11 (d), the effective bending length can be shortened at the time of the positive force and the negative force,
An independent basic model can be realized without reducing the strength.

[Brief description of the drawings]

FIG. 1 is a partially enlarged plan view showing a strength member of an entire building to which a structural strength improving structure in a foundation for construction of the present invention is applied.

FIG. 2 is a longitudinal sectional side view showing, in an enlarged manner, the vicinity of the proof stress improving structure.

FIG. 3 is a longitudinal sectional side view showing the proof stress improving structure in an enlarged manner.

FIG. 4 is a side view showing an aspect of joining between underground beams using various members.

FIG. 5 shows a structure for improving the proof strength of the construction foundation of the present invention.
It is a perspective view which shows the aspect applied to the foundation structure which connected the underground beam to the pillar erected on the abandoned concrete in a corner part.

FIG. 6 is a perspective view showing an aspect applied to a foundation structure formed by connecting underground beams in the T-shaped portion of the same.

FIG. 7 is a perspective view showing a mode in which a support box and a load-bearing plate are provided at positions where pillars are installed in the straight section, and an underground beam is connected to the support box. .

FIG. 8 is a skeletal plan view showing how a fire plate is installed.

FIG. 9 is a perspective view showing a connection mode when a bracket beam is provided to the column unit.

FIG. 10 is a skeletal plan view showing an installation mode of a bracket beam corresponding to an increase in load.

FIG. 11 is a skeletal side view showing a stress applied to a building and how the stress is dispersed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Foundation for construction 1A Foundation structure 2 Building 3 Column unit 3a Base plate 3b Bolt hole 3c Column 3d Outrigger 5 Root room 6 Split stone 7 Discarded concrete 8 Concrete 11 Underground beam 11a Upper flange 11b Lower flange 11c Web 11d Bolt hole 12 Lower reinforcing bar 13 Upper reinforcing bar 14 Spacer 14a Fixed spacer 14b Adjustable spacer 15 Gusset plate 15a Bolt hole 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 30 Strengthening structure 31 Bracket beam 31a Upper flange 31b Lower flange 31c Web 31d Bolt hole 32 Fire plate 32a Hole F Stress GL Standard Board

Claims (5)

[Claims] An underground beam is combined with an appropriate plane frame, or a pillar is combined with the underground beam to form a foundation structure, and furthermore, the foundation structure is applied to a construction foundation surrounded by concrete to a certain extent. In the joint structure of the beam connection portion, an underground beam from two or three directions is connected to the column-beam connection portion, and the plane shape of the column-beam connection portion is cross-shaped with the underground beam. A structure for improving the strength of the foundation for construction, characterized by the provision of bracket beams as described above. 2. The structure according to claim 1, wherein said foundation structure is of an independent foundation type. 3. The structure according to claim 1, wherein the bracket beams or the bracket beam and the underground beam are joined to each other by a fire plate. 4. The structure for improving the strength of a construction foundation according to claim 3, wherein a hole for flowing down the concrete is formed in the fire plate. 5. The pillar-beam connection part is a pillar unit lower end part, and a base plate provided at a lower end of the pillar unit has a portion outside a width dimension of an underground beam connected to the pillar,
5. The structure for improving the strength of a construction foundation according to claim 1, wherein a lug portion is provided.