JPH0737726B2 - Construction method of underground structure - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for constructing an underground structure of a building or an underground structure such as an underground parking lot.

[Conventional technology]

To construct an underground structure, conventionally, after constructing a column as a temporary structure, a temporary cutting beam or bulge for mountain retaining is also erected, and as the root cutting progresses, this cutting beam is divided into two stages, It will be gradually increased to 3 steps.

When the underground structure becomes large with 5 or 6 layers underground, the number of steps of this girder naturally increases and the amount of temporary material also increases.

By the way, if the pillars and beams of the permanent construction can also be used as temporary constructions for the mountain retaining, the economic efficiency will be significantly improved, and the above-ground construction work can be carried out at the same time except for the slab on the first floor. Productivity is also significantly improved.

There is one of the following construction methods as the permanent beam construction method. Firstly, the core column (steel tube column) of the permanent construction is installed at the time of pile construction, and then the steel box beam, which is the conventional beam, is installed. .

After that, concrete is poured into the inside to construct a supporting structure for the retaining wall, and the next excavation work is started.

Furthermore, a steel box beam on the floor directly below will be installed, and internal concrete pouring and excavation will be repeated to proceed with the underground structure work.

[Problems to be Solved by the Invention]

Such a conventional permanent beam construction method is a special one that uses a steel tube column and a steel box beam that are filled with concrete, and does not use a normal steel column or steel beam.

If ordinary steel columns or steel beams are used, first of all, it is difficult to construct the core columns (pile core columns),
Since the dimensional accuracy of construction is inevitable (vertical angle becomes diagonal), it cannot be used as a permanent steel column in many cases.

In addition, the length of the beam (cut beam) attached to it is a dimension that matches the site, so it cannot be used as a permanent beam.

The object of the present invention is to eliminate the inconvenience of the above-mentioned conventional example, and to construct a cutting beam for mountain retaining using a normal steel column or steel beam,
This can be fully used as a pillar / beam for main installation,
It is to provide a method of constructing an underground structure that can fully utilize the characteristics of the permanent beam construction method.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention builds a pillar underground,
The pillar / beam structure constructed by constructing a beam on the top of this pillar is used as a cutting girder for mountain retaining, and the second and subsequent beams are erected on the bottom of the pillar according to the depth of root cutting. In the construction method of constructing an underground structure, the pillar is a pile core pillar provided with a pressing means to the outside on the side part, and this pile core pillar is built into the hole that has been chiseled as a steel pillar for main construction, and the pressing means Correct the installation accuracy by adjusting the pressure on the hole wall, give concrete consolidation to the bottom of the pile core pillar, and connect this pile core pillar and the permanent steel beam that also serves as a cut beam to form a male screw bolt part at one end, Use a metal joint having a flat plate portion with a bolt insertion hole at the other end, screw an adjustment nut into the bolt portion of this metal joint, insert the bolt portion into the steel column flange, and tighten the metal joint. The flat plate is placed on the steel beam flange, tightened with bolts and nuts, and It is an Abstract that performed by connecting the flange and beam web in the gusset plates.

[Action]

Conventionally, to use a pillar or a girder that has been constructed as a temporary structure as a main structure, it is necessary to improve the installation dimension accuracy of the column. It is possible.

According to the present invention, the installation dimension accuracy of the pile core column is such that the inclination in the hole of the core column can be easily corrected as a reaction by adjusting the pressure of the pressing means provided on the side portion of the pile core column to the hole wall. It can be highly accurate.

Further, the joining of the steel frame beam to the pile core column can be adjusted by rotating the adjusting nut screwed to the bolt portion formed at one end of the joint metal to change the degree of insertion of the bolt portion into the steel column flange.

Further, since this joint metal can be retrofitted to the pile core pillar, it is not necessary to provide a protrusion such as a bracket for jointing with the steel frame beam at the time of construction of the pile core pillar, and it is not necessary to increase the hole diameter.

〔Example〕

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 to 4 are side views showing respective steps of the method for constructing an underground structure of the present invention. First, as shown in FIG. 1, an earth pressure wall 1 is formed in the ground, and the earth pressure wall is formed. A hole 2 is formed on the inner side, which is surrounded by 1, by an excavator as necessary.

The hole 2 may be formed by disposing a steel pipe casing.

Next, a steel-framed column 3 as a pile core column is built in this hole 1. The steel-framed column 3 is pressed outward on its side, that is, the surface of the flange 3a (a web is also possible), as shown in FIG. A jack 4 was provided as a means.

The jack 4 may be a manual type with a screw structure,
It may be a hydraulic jack or an air jack, and can be remotely operated at least near the upper end of the steel column 3.

Before the steel pillar 3 is installed, the jack 4 is contracted so that it does not project, and after the steel pillar 3 is installed in the hole 1, the jack 4 is appropriately extended by the remote control so that the hole wall The tilt of the steel column 3 in the hole 1 is corrected as a reaction by adjusting the pressure applied to the.

After the installation accuracy of the steel column 3 is corrected in this way, the concrete 5 is poured into the lower part of the steel column 3 as shown in FIG.

Then, the steel beam 6 is joined to the upper end of the steel column 3 by joining or the like, and the steel beam 6 serves as a first-stage beam.

In addition, since this steel beam 6 is a floor beam of the 1st floor of a building on the ground floor, and the excavation depth is extremely shallow immediately from the ground, a bracket or a joint is formed with the steel column 3. Then, the usual joining method of joining is used.

Then, as shown in the third, the steel beam 6 is used as a cutting beam for mountain retaining to perform root cutting, and the steel beam 7 is attached to the steel column 3 as a second-level cutting beam according to the depth. To join.

Also, the steel frame erection to the ground floor will start at the same time.

Joining of the steel beam 7 and the steel column 3 is carried out by using a metal joint 8 as shown in FIGS. 3 and 4, and as shown in FIGS. Has a flat plate portion 8b having a male screw bolt portion 8a formed at one end and a bolt insertion hole 8c formed at the other end.

The flange 3a of the steel column 3 is formed with an insertion hole through which the bolt portion 8a is inserted. The bolt portion 8a is inserted into the insertion hole, and the adjustment nut 10, with the joint receiving member 9 interposed. Screw 10 '.

On the other hand, an insertion hole is also formed in the flange 7a of the steel beam 7, and the flat plate portion 8b of the metal joint 8 is the flange 7a of the steel beam 7.
And tighten them with bolts and nuts 11.

And in such joining, there is still an error in the installation dimension of the steel column 3. To correct this, the adjustment nut
Steel column flange 3a of bolt part 8a of metal fitting 8 with rotation of 10
It is done by changing the insertion degree.

Then, a joining gusset plate 13 having a hole for bolting is preliminarily provided on the flange 3a of the steel column 3 by welding or the like in a direction orthogonal to the surface of the flange 3a, while the steel frame An elongated hole 14 is also formed in the end portion of the beam 7 on the joining side of the web 7b as a hole for bolting so that the tightening position of the bolt can be adjusted.

Then, the splicing plate 12 is overlapped with the joining gusset plate 13 and the joining side end portion of the web 7b of the steel beam 7 in which the elongated hole 14 is formed, and bolted, so that the steel pillar 3 The flange 3a and the web 7b of the steel beam 7 are joined together.

In this way, the steel column 3 and the steel beam 7 can be joined at a place other than the joining point of the metal joint 8.

As shown in FIG. 4, when the steel beam 7 as the second-stage cutting beam is erected in this way, the root cutting is performed in the same manner, and the cutting of the third or lower stage is performed according to the excavation depth. A steel beam 7 as a beam is also erected using a joint metal 8.

In such a joint between the steel frame column 3 and the steel frame beam 7, the beam axial force due to the earth pressure acting from the earth pressure wall and the shear force transmitted from the beam to the column are gusset plate 12 between the steel frame column 3 and the steel frame beam 7. And the bending moment of the steel beam 7 is transmitted through the beam 7.
At the end, it is transmitted to the column 3 as a pair of couples, and during this couple, the tensile force is applied to the column 3 by using one nut screwed to the bolt portion 8a through the joint metal 8 as a reaction point and to the column 3. Are transmitted to the columns 3 by using the other nut as a reaction point.

Then, when the subway bone construction is completed, the underground concrete skeleton 15 is constructed.

〔The invention's effect〕

As described above, the method of constructing an underground structure of the present invention is the same as that used as a temporary construction for mountain retaining as it is for pillars for main construction.
Since it can also be used as a beam, it is possible to improve the economic efficiency, and it is possible to proceed with the above-ground construction at the same time, so that the productivity is improved by shortening the construction period.

And, in order to use the pillars and girders constructed as temporary construction as main construction in this way, there are many versatile steel columns,
Since a steel beam can be used, it is possible to improve the installation dimension accuracy of a column and adjustment of the joint between the column and the beam, which could not be performed conventionally, easily and reliably.

[Brief description of drawings]

1 to 4 show one embodiment of a method for constructing an underground structure according to the present invention. Side views showing each step, FIG. 5 is a side view of a main part, and FIG. 6 is a plan view of the same. Is. 1 ... Earth pressure wall, 2 ... Hole 3 ... Steel column, 3a ... Flange 4 ... Jack, 5 ... Rooted concrete 6,7 ... Steel beam, 7a ... Flange 7b ... Web 8 ... … Molding hardware, 8a …… Bolt part 8b …… Plate part, 8c …… Bolt insertion hole 9 …… Molding hardware, 10,10 ′ …… Adjustment nut 11 …… Bolt / nut, 12 …… Splice plate 13… … Gazette plate, 14 …… Oval hole 15 …… Underground concrete frame

Claims (1)

[Claims] 1. A pillar / beam structure constructed by constructing a pillar in the basement and installing a beam on the upper part of the pillar is used as a girder for a mountain retaining, and the pillar is sequentially constructed according to the depth of root cutting. In the construction method of constructing the underground structure by erection the beam of the second step or less at the bottom,
The pillar is a pile core pillar provided with outward pressing means on the side, and the pile core pillar is built into the hole that is perforated as a steel pillar for main construction, and the accuracy of installation is adjusted by adjusting the pressing of the pressing means to the hole wall. The concrete core was fixed to the bottom of the pile core pillar, and the pile core pillar and the main steel frame beam that also serves as a cutting beam were joined with each other by a male screw bolt part formed at one end and a bolt insertion hole formed at the other end. Using a joint metal having a joint, screw an adjusting nut to the bolt of this joint, insert the bolt into the steel column flange, and tighten the flat plate of the joint metal to the steel beam flange and bolt it.・ A method of constructing an underground structure characterized by tightening with nuts and connecting the column flanges and beam webs with gusset plates.