JPH0663237B2 - Construction method of basement - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for constructing a basement floor of a building such as a reinforced concrete structure, and in particular, constructing a crossbeam near the ground surface and supporting it. It relates to the construction method of the basement floor where the basement floor is excavated.

[Prior Art] When a building is made of reinforced concrete and construction of the basement is preceded, it is generally necessary to rotate the earth retaining rod up to four laps for excavation work and to support it with a girder. is there. At this time, the construction of piles or basement pillars from the ground is preceded, a girder is erected at the floor position on the first floor, root excavation is performed under the bearing, and the outer wall concrete is hammered back. There are known construction methods for the basement floor, such as a construction method that promotes excavation downwards and a construction method that constructs an outer wall upwards from the bottom after completion of excavation.

Further, it is often performed that a temporary steel material is used as the cutting beam or a concrete floor beam made of concrete is first constructed.

[Problems to be Solved by the Invention] However, in the construction of piles or basement columns from the ground, there is a limit to the accuracy, and at the joints between the piles or basement columns and concrete floor beams, The current situation is that the work of each type of work is concentrated, labor is required in a large number of places, workability is unavoidable, and such drawbacks are not recognized.

[Means for Solving the Problems] The present invention eliminates the above-mentioned drawbacks, and as a problem, improves the structure of a joint between a preceding pile or an underground floor column and a floor beam, and The purpose is to provide a construction method for the entire basement floor. Prior to the construction of piles or basement pillars from the ground, the main floor floor beam of the first floor is erected on top of it to form a cut beam. , In the construction method of the underground floor where root excavation was carried out under the support, especially the process of connecting the steel column to the top of the pile and placing it in the ground in advance, at the top of the column, A process of loosely fitting a precast concrete joint with a through hole in the center and inserting it into the pillar to attach it, a step of connecting a precast concrete beam to the joint, and a step of post-casting concrete to the steel pillar. It is characterized by including. This has succeeded in achieving the purpose of improving the construction method at the joint with the concrete main beam at the top of the basement.

[Example] The construction method of the basement floor of the present invention will be described in detail with reference to the drawings showing a preferred example. FIG. 1 is a sectional view of a basement floor portion of a reinforced concrete building to which the present invention is applied, and FIG. 2 is a plan view of a joint portion between a column and a beam. In the figure, 1 is a reinforced concrete building, 2 is the ground, 3 is the outer wall of the basement of the building 1, 4 is a pile, 5 is the base of the basement, 6 is the pillar of the basement, and 7 is the ground floor. Floor beams,
8 is the floor slab.

The pile 4 is cast as a concrete cast-in-place pile to a predetermined depth in the ground 2 that supports the bottom 5, and its top portion 21
The lower end portion 62 of the steel core pillar 61 of the pillar 6 is embedded and connected thereto. A bracket 64 for mounting the joined body 10 of the pillar 6 and the beam 7, which is a feature of the present invention, is fixed to the top portion 63 of the core pillar 61.

As shown in FIG. 2, the joined body 10 includes a main body 11 at the center.
And a plurality of arm portions 12 projecting corresponding to the beam 7, which is a molded body made of precast concrete (hereinafter referred to as “PC”).
A through hole 13 for loosely fitting and inserting 1 is formed, and a joining means 72 for joining to the beam 7 is provided at a tip of an arm portion 12 shown in a part
Is provided. A plurality of sleeves 14 for inserting reinforcing bars for joining the upper and lower columns 6 are embedded around the through hole 13, and are supported by the bracket 64 around the through hole 13.

In the beam 7, the intermediate portion 71 is formed as a PC beam, and the base end portion of the connecting member 72 made of steel is embedded and protruded at the end portion on the side of the column 6 so as to be provided in the arm portion 12. Is connected to the connecting member 72. The outer end 7 on the outer wall 3 side
A similar connecting member 72 is also provided on the outer wall 3 of the outer wall 3 as well.
The beam 7A is connected to the steel frame 74 of the beam 7A on the outer periphery supported by the bracket 32 provided on the top 31 of the beam 7A, and the beam 7A is a bulge of the outer wall 3 with the beam 7 as a cut beam. 75 in the figure is a concrete beam.

The PC beam 71 and the joint 10 are formed lower than the floor surface by the thickness of the slab 8, and the PC beam 71 and the arm 12 of the joint 10 are cast integrally with the beam 75 and the concrete of the slab 8. Connected by crushed concrete.

In this way, the floor beam 7 that is permanently installed is formed, and after it has a function as a girder for uprising, concrete 65 is placed around the core column 61 to form the column 6
Is completed. At this time, the upper portion of the reinforcing bar 66 of the pillar 6 is connected to the reinforcing bar of the pillar 6 on the upper floor through the sleeve 14.

The top portion 63 of the steel core post 61 inserted into the through hole 13 is
Since it is loosely fitted in the through hole 13, it is installed with sufficient accuracy in the joined body 10 and is integrally connected by the concrete 65 of the pillar 6 and the concrete of the slab 8.

Needless to say, the configuration of the present invention is not limited to the above-described embodiment. For example, the pile 4 has the core column 6 at the top 41 thereof.
1 can be replaced with a steel pile, a PC pile or the like as long as it is connected by connecting the lower end portion 61 of the No. 1 and buried in advance.
The means for joining the joined body 10 and the PC beam 71 is not limited to the steel plate member 72.

[Operation] Since the basement floor construction method of the present invention forms the basement having the above-described configuration, its construction can be easily performed by applying the joined body 10 of the present invention to a normal construction method. It can be carried out. The operation of the present invention thus configured will be described with reference to FIG. In the figure, first, a cast-in-place concrete pile 4 is cast from the ground to a predetermined depth, and while its hardening does not proceed sufficiently, its top part 41
The lower end portion 62 of the steel core column 61 is inserted into and connected to.

Then, a joined body 10 separately molded by a prefab
When the joint body 10 is fitted and inserted from the top portion 63 of the core column 61, the joined body 10 is stably supported on the bracket 64, and the concrete 65 of the column 6 under the bracket 64 can be constructed.

On the other hand, a beam 7A is constructed at a position inside the outer wall 3,
If the PC beam 71 is arranged between the zero arm part 12 and the beam 7A and their ends are connected by the joining member 72 and the floor beam 7 is completed, the excavation work in the next step becomes possible. .

The construction method of the outer wall 3 associated with the excavation is arbitrary, and normally, the reverse construction method is adopted under the support of the permanent floor beam 7.

Here, in the present invention, since the bonded body 10 is configured as described above, it is extremely easy to mount the core pillar 61 on the top portion, and the through hole 13 allows the pillar 6 to be mounted.
Since it can be fixed after securing the joining accuracy between the beam and the beam 7, the axial force of the cutting beam is safely transmitted, and it is not necessary to use a detailed steel product such as a gusset.

[Effects of the Invention] In the construction method of the basement floor of the present invention, the construction of the pile or the basement column from the ground is preceded, and the main floor floor beam of the first floor is erected at the top of the pile to form a girder, and its support. In the construction method of the basement floor where the root excavation was performed under the condition, the step of connecting the steel column to the top of the pile and placing it in the ground in advance, at the top of the column,
A process of loosely fitting a precast concrete joint with a through hole in the center and inserting it into a pillar to attach it, a step of connecting a precast concrete beam to the joint, and a step of post-casting concrete to a steel pillar Therefore, by arranging a joint body in which the joints of piles or columns and beam beams using the floor beam of the permanent construction are formed in advance, it is possible to easily and accurately carry out the construction of complicated structures. Can be well formed. Therefore, in the present invention, prior to excavation excavation that is indispensable for the construction of the basement, while the floor beam of the main construction is used as the cutting beam, the rational connection between the pile, the pillar and the cutting beam is secured. In particular, the adoption of the PC member greatly contributes to the reduction of labor cost and construction period, and therefore can be applied to the construction method of the underground floor to solve the problem.

[Brief description of drawings]

The drawings are for explaining the construction method of the basement floor of the present invention based on examples, FIG. 1 is a sectional view of the basement floor portion of a reinforced concrete building adopting the present invention, and FIG. 2 is a pillar It is a top view of the junction part of a beam and a beam. 1 ... Building, 2 ... Ground, 3 ... Exterior wall, 4 ... Pile, 5 ... Bottom board,
6 ... Pillar, 7 ... Floor beam, 8 ... Floor slab, 10 ... Joined body, 11
... body part, 12 ... arm part, 13 ... through hole, 14 ... sleeve, 61 ... core post, 62 ... lower end part, 63 ... top part, 64 ...
Bracket, 65 ... Concrete, 71 ... PC beam, 72
... Joining member.

Claims (1)

[Claims] [Claim 1] Construction of piles or basement pillars from the ground is preceded, and a permanent floor beam on the first floor is erected on the top of the pile to form a cut beam, and root excavation is performed under the bearing. In the construction method of the basement, the step of connecting a steel column to the top of the pile and placing it in the ground in advance, at the top of the column, play a precast concrete joint with a through hole in the center. Fit,
A method for constructing a basement floor, which includes a step of inserting and fastening to a pillar, a step of connecting a beam of precast concrete to a joint, and a step of post-casting concrete to a steel pillar.