JPH0748847A - Steel frame column base section structure for building with underground floor and underground skeleton construction method - Google Patents

Abstract

PURPOSE:To shorten the construction period and reduce the construction cost when constructing the skeleton of the underground floor by the inverted construction method. CONSTITUTION:An earth retaining wall 2 is constructed around an underground skeleton A to be constructed, support piles 1 are formed below the lowest floor of the underground skeleton A, and steel framed columns 3 of the underground floor are erected at the upper end sections of the support piles 1. The plot ground surrounded by the earth retaining wall 2 is excavated to the position below the beam of the ground first floor and a steel framed beam 5 of the ground first floor is suspended between the steel framed columns 3, 3, and a floor slab 8 of the ground first floor is constructed on it. The plot ground is further excavated to the position below the beam of the underground first floor, a steel framed beant 5 of the underground first floor is suspended between the steel framed columns 3, 3, and a floor slab 8 of the underground first floor is constructed on it. Underground skeletons A of the underground second floor and the underground third floor are likewise constructed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel column post structure for a building having a basement and a method for constructing an underground structure.

[0002]

2. Description of the Related Art Generally, when a large horizontal force such as seismic force acts on a building having a basement floor, most of the horizontal shearing force acting on the column base on the first floor is above ground. It is known that it is transmitted from the floor slab on the first floor to the earth pressure wall around the building, and not to the columns and beams except the outer periphery of the basement floor.

Therefore, the SRC structure and the S structure in which the joints of the skeletons such as columns and beams on the basement floor are rigidly joined are
There were issues such as being extremely uneconomical.

Even when the skeleton of the basement floor of a building is constructed by the so-called upside-down construction method, the skeleton of columns, beams, etc. is often constructed by RC structure or SRC structure.

However, the RC structure and SRC
If you try to build it with a structure, there are problems such as a long construction period and inevitable cost increase.

[0006] The present invention has been made to solve the above problems, and it is possible to smoothly transmit a large horizontal shearing force such as seismic force to the surrounding earth pressure wall at the column base of the ground floor of the building. Also, when constructing the structure of the basement floor by the reverse construction method, we provide the construction method of the steel pillar column base structure and the basement structure of the building with the basement floor that made it possible to shorten the construction period and reduce the construction cost The purpose is to do.

[0007]

A structure of a steel column post of a building having a basement floor according to claim 1 of the present invention is
A diaphragm is projected on the column base of the steel column, and the floor slab on the ground floor of the building is constructed by reinforced concrete,
In addition, a plurality of shear reinforcing bars are arranged in the concrete of the floor slab and the ends thereof are joined to the diaphragm.

According to a second aspect of the present invention, there is provided a construction method for an underground skeleton, in which a cliff wall is constructed around an underground skeleton to be constructed, and then a construction is performed below the lowermost floor of the underground skeleton. Create a support pile, then build a steel column on the basement floor at the upper end of the support pile, and then excavate the site ground surrounded by the cliff wall to the beam below the ground floor. , Next, erected a steel beam on the ground floor between the steel columns, build a floor slab on the ground floor on it, then excavate the site ground further down to the beam below the ground floor, Next, a steel frame beam on the first basement floor is erected between the steel frame beams, a floor slab on the first basement floor is constructed on the steel beam, and thereafter, an underground frame structure on the second basement floor and the third basement floor is similarly constructed.

[0009]

【Example】

Example 1. 1 and 7 show the first claim according to the present invention.
An example of a steel column post structure of a building having a basement described in paragraph is shown, and in the figure, reference numeral 1 is a support pile that is constructed below the foundation slab of the substructure A and supports the substructure A, 2 Is built around this underground structure A,
The rock retaining wall 3 for preventing the collapse of the surrounding ground is a steel pillar of the underground skeleton A built on the support pile 1, and 4 is projectingly provided at the tip of the steel pillar 3 to support the support pile 1. Structural columns 5 inserted into the concrete are 5 steel beams of the substructure A joined to the joints of each floor of the steel columns 3, and 6 and 7 are the steel beams 5 of each floor of the steel columns 3. A joint plate and high-strength bolts to be joined to the mouth portion, 8 is a floor slab on each floor of the substructure A constructed on the steel beam 5, and 9 is a shear reinforcing steel bar reinforced in the concrete of the floor slab 8. , 10 are diaphragms for joining the ends of the shear reinforcing bars 9 to the steel columns 1, and reference numerals 11 and 12 are the foundation slabs and foundation beams constructed on the lowest floor of the underground structure A.

The earth retaining wall 2 is constructed by a generally employed earth retaining construction method such as a steel sheet pile construction method.

Further, a square steel pipe or a circular steel pipe is used for the steel frame column 3, and a steel frame column 3a on the ground floor is provided at the upper end of the steel frame column 3 on the basement floor in the concrete of the floor slab 8 on the ground floor. Joined through 10. In this case, the steel column 3 may be penetrated and the diaphragm 10 may be attached to the periphery of the steel column 3. Alternatively, a steel pipe concrete column may be formed by placing concrete in the steel frame column 3.

The H-shaped steel is used for the true-columns 4, and the true-columns 4 are joined to the tip ends of the steel columns 3 by welding, and the upper ends of the support piles 1 before the concrete of the support piles 1 hardens. When the support pile 1 is inserted into the section, and the concrete of the support pile 1 hardens, the support pile 1 stands on its own.

The H-shaped steel is used for the steel beam 5 of each floor, and both ends of the steel beam 5 of each floor are connected to a plurality of joint plates 6 projecting from the joints of each floor of the steel column 3. It is joined by a high-strength bolt 7.

In this case, only the web 5a of the steel beam 5 is joined to the joint plate 6 and the ends of the upper and lower flanges 5b are free from the steel column 3. Therefore, the bending stress from the steel beam 5 is designed not to be transmitted to the steel column 3.

A part of the shear reinforcing bar 9 is diagonally arranged in the concrete of the floor slab 8 and both ends thereof are joined to the diaphragm 10, whereby the floor slab 8 on each floor is integrated with the steel column 3. It is joined.

Thus, a large shearing force acting on the column base of the steel column 3a on the ground floor during an earthquake or a typhoon is surely applied to the surrounding earth pressure wall 14 via the floor slab 8 on the ground floor. Designed to be transmitted to.

In the embodiment, the structure of the floor slab 8 on each floor and the structure of the joint between the floor slab 8 and the steel column 3 are the same, but the shearing force at the time of an earthquake is the same as that on the ground. Since it is transmitted to the earth pressure wall around the building through the floor slab 8 on the floor, the floor slab 8 below the second floor may have a simpler configuration.

Example 2. Next, an underground skeleton construction method according to claim 2 of the present invention will be described in order.

First, the earth retaining wall 2 is constructed around the underground structure A to be constructed by a conventionally used earth retaining method such as a sheet pile method.

Next, a support pile 1 made of cast-in-place concrete is formed below the foundation slab of the underground structure A.

Next, immediately after placing the support pile 1 into concrete and before the concrete is hardened, the steel frame column 3 having the steel true column 4 protruding in advance at the tip is built.

Next, the site ground in the mountain retaining wall 2 is dug down to the bottom of the beam on the first basement floor to be erected (primary excavation).

Next, when the primary excavation is completed, the steel beam 5 on the first basement floor is bridged between the steel columns 3 and 3, and both ends of the steel plate 5 are projected from the joint plate of the steel column 3. 6 are joined by a plurality of high-strength bolts 7. In this case, by joining only the web 5a of the steel beam 5 to the joint plate 6, a so-called simple beam structure is formed.

Next, the floor slab 8 on the first floor above the ground is constructed on the steel beam 5 on the first floor below. In this case, a part of the reinforcing steel bars 9 is diagonally arranged in the concrete of the floor slab 8, and both ends of the reinforcing steel bars 9 are connected to each other via the gusset plates 10.
To join.

Although the end of the reinforcing bar 9 may be joined to the gusset plate 10 by welding, a screw type coupling coupler (not shown) is welded to the gusset plate 10 in advance in a factory or the like. If the end portions of the reinforcing bar 9 are screwed together and joined together, there is no welding work of the reinforcing bar 9 in the field, and the reinforcing bar 9 can be reliably joined to the gusset plate 10.

Next, the ground excavation is started again, and the ground is excavated to the bottom of the beam on the second basement (secondary excavation).

Next, when the secondary excavation is completed, the steel beam 5 on the second basement floor is bridged between the steel columns 3 and 3, and both ends of the steel beam 5 are projected from the joint of the steel column 3. The plate 6 is joined with a plurality of high-strength bolts 7, and subsequently, the floor slab 8 on the first basement floor is constructed on the steel beam 5 on the second basement floor. In this case, the joining of the ends of the steel beam 5 and the construction of the floor slab 8 are performed by the same method as above.

Thereafter, in the same manner, the skeletons on the third and lower basements are constructed, and finally, the foundation slab beam 11 and the foundation beam 12 on the bottom floor are constructed. In addition, you may provide the drainage pit 13 as shown in FIG.

[0029]

As described above, according to the steel column post base structure of a building having an underground floor according to the first aspect of the present invention, a large horizontal shear acting on the column base of the steel post is provided. There is an effect that the force can be reliably and smoothly transmitted from the floor slab to the earth pressure wall around the building.

Further, according to the method for constructing an underground skeleton according to the second aspect of the present invention, since the columns and beams of the basement are all constructed by steel pipes and steel beams, formwork construction and concrete construction work are performed. Since there is no such problem, the construction period can be greatly shortened and the construction cost can be reduced.Besides, the steel beams on the floor directly above the ground will be cut as the cutting beams to support the retaining walls, so there is no special cutting beam. Both have the effect that the root cutting work can be performed extremely safely.

[Brief description of drawings]

FIG. 1 is a partial vertical cross-sectional view of a basement floor showing a structure of a basement floor of a building.

FIG. 2 is a partial vertical cross-sectional view of a basement floor showing a structure of a basement floor of a building.

FIG. 3 is a cross-sectional view showing the structure of a steel column post.

FIG. 4 is a vertical cross-sectional view showing the structure of a steel column post.

FIG. 5 is a cross-sectional view showing the structure of a steel column post.

FIG. 6 is a cross-sectional view showing the structure of a steel column post.

FIG. 7 is a vertical cross-sectional view showing the structure of a steel column post.

[Explanation of symbols]

1 ... Support pile, 2 ... Mountain retaining wall, 3 ... Steel column, 4 ... True column,
5 ... Steel beam, 6 ... Connection plate, 7 ... High-strength bolt, 8 ...
Floor slab, 9 ... Reinforcing bar, 10 ... Diaphragm, 11 ... Foundation slab, 12 ... Foundation beam, 13 ... Drainage pit, 14 ... Earth pressure wall, A
… The basement building.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location E04G 21/14 9234-2E

Claims (2)

[Claims] 1. In a steel column post structure of a building having a basement, a diaphragm is projected on the column base of the steel column, and a floor slab on the ground floor of the building is constructed by reinforced concrete, and A steel column post structure of a building having a basement, wherein a plurality of shear reinforcing bars are arranged in concrete of the floor slab and the ends thereof are joined to the diaphragm. 2. A dam wall is constructed around the underground structure to be constructed, and then a support pile is formed below the lowermost floor of the underground structure, and then the basement is formed at the upper end of the support pile. Building a steel column on the first floor, then excavating the site ground surrounded by the cliff wall to the position below the beam on the first floor above the ground, and then constructing a steel beam on the first floor above the steel column. , Constructing a floor slab on the first floor above the ground, then excavating the site ground further to the position below the beam on the first basement, and then constructing a steel beam on the first basement between the steel beams, An underground skeleton construction method characterized by constructing a floor slab on the first basement floor above, and similarly constructing an underground skeleton on the second basement floor and the third basement floor.