JPH0776914A - Hanging-down construction method of steel stairs - Google Patents

Abstract

PURPOSE:To increase usability and safety on works, by forming lasting steel stairs in the basement as a hanging structure from a prior working floor and moving down the stairs gradually in accordance with the advancement of excavation. CONSTITUTION:An opening 2 for a lasting steel stairs is opened in the floor plate 1 on the first floor on the ground and a bracket is temporarily installed on the upper edge of the opening 2. And the primary excavation is carried out on the first basement and leveling concrete is placed on the excavated bottom. Next, the first stratum 3a of the lasting steel stairs 3 is hung up by a lifter 5 and inserted in the opening 2 and the upper part of steel posts 31 is fixed to the bracket and hung down. And the underground frame construction works like the floor 7, posts, external walls, etc., of stairs 3 are carried out. And further, the same processes are repeated by turns to connect the second and third strata 3b, 3c to each other so as to construct the stairs 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel staircase hang-down method in which a permanent steel staircase on a basement floor is used as a temporary staircase at the time of root cutting.

[0002]

2. Description of the Related Art In recent years, a reverse construction method has often been adopted for the construction of underground structures of various concrete buildings because of advantages such as a shortened construction period. In this reverse construction method, after constructing a mountain stop and a structure column, root cutting and building work are repeated toward the basement to build an underground structure one after another. Not only early construction of the underground structure is possible. , It is also excellent in that it is possible to proceed with the ground frame work at the same time.

[0003]

However, in this reverse driving method, the floor on the first floor above the floor that also serves as a working floor is usually constructed, and then the floors on the lower floor are sequentially built. Until the floor is completed, the permanent steel stairs cannot be assembled and used, and for this reason, temporary rooting equipment is used during root cutting. Therefore, it takes a lot of time and effort to assemble and dismantle the lifting equipment, and the construction of the permanent steel stairs is delayed, which diminishes the advantage of the reverse cornering method. In addition, temporary lifting facilities are not enough in terms of convenience and safety. Therefore, the present invention solves the above-mentioned conventional problems by making it possible to temporarily use the main steel frame stairs as a lifting facility in the reverse driving method, and in addition,
It is intended to reduce the cost.

[0004]

In order to achieve the above object, the present invention has a structure in which a permanent steel staircase on a basement floor is suspended from a preceding work floor, and the permanent steel staircase is adapted to the progress of root cutting. It is characterized in that it is inserted downward at any time.

[0005]

[Advantage] With the above structure, the permanent steel staircase that is finally fixed to the underground structure can be temporarily used for the lifting equipment, and the conventional temporary lifting equipment is unnecessary or can be reduced to a very small amount. to enable.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings show an embodiment of the steel frame stair hang-down method of the present invention, of which FIGS. 1 to 5 show the construction procedure. Hereinafter, this will be sequentially described. (1) First step (Fig. 1) First, we construct the cliffs and structure columns to construct the floor 1 on the first floor above the ground floor, which doubles as a working floor. 6 forms an opening 2 for the permanent steel staircase, which is also shown in FIG. 6, which is an enlarged plan view, and makes the steel columns 31 at the four corners of the permanent steel staircase 3 correspond to the upper edges of the opening 2 at appropriate positions. To temporarily install the bracket 4. Then, a primary root cutting A suitable for the construction of the first basement floor is performed, and the primary root cutting bottom Aa is thrown away with concrete concrete Ab. On the other hand, on the ground, corresponding to the first root cutting A, the first layer portion 3a adapted to the lower half of the third floor portion of the basement floor, which is the lowest floor, is assembled in correspondence with the first root cutting A. In this first layer portion 3a, a plurality of steel receiving beams 32 are joined to each other in the front and rear of the steel columns 31 at the four corners, and a plurality of landings 34 are provided between the front and rear steel receiving beams 32. The steel stairs 33 are installed alternately and the required steel handrails 35 are attached. However, since the inner handrail at the landing 34 at the upper end is unnecessary later, a temporary handrail frame 15 is used. Further, a frame reinforcing member 36 is provided horizontally at the lower ends of the steel columns 31. The reason why the first layer portion 3a is adapted to the lower half of the third floor of the basement floor is that the floor height of the third floor of the basement floor is designed to be almost double that of the first floor of the basement floor. Then, the first layer portion 3a of the permanent steel staircase 3 is lifted by a crane or the like (not shown) through the suspending means 5 and inserted into the opening 2 to make the steel. Bolt the upper part of the pillar 31 to each bracket 4 above.
Removably connect with a nut and hold it in a suspended state. In addition, a temporary slope pier 6 is spanned between the abandoned concrete Ab and the lower end of the first layer portion 3a of the permanent steel staircase 3. In this way, by temporarily using the first layer portion 3a of the permanent steel staircase 3, the floor 7 of the first floor of the basement floor,
Underground construction work for pillars, outer walls, etc. will be performed.

(2) Second step (Fig. 2) After the substructure of the first floor of the basement floor is constructed, the second root cutting B suitable for the construction of the second floor of the basement floor is performed and the second root cutting bottom Ba is formed. Hit abandoned concrete Bb. In addition, on the floor 1 of the first floor above the ground floor, which is the work floor, in correspondence with the second root cutting B, the first half of the permanent steel stairs 3 that is adapted to the upper half of the third floor of the basement floor, which is the lowest floor. The two-layer part 3b is assembled and connected and integrated with the upper end of the first layer part 3a. However, the handrail frame temporarily installed at the landing 34 at the upper end of the previous time
I removed 15 because it is useless, but I will divert it to the landing 34 at the top of this time. The reason why the structure of each part of the second layer part 3b is also the upper half of the third floor part of the basement is the same as in the case of the first layer part 3a. Next, at the upper end of the second layer portion 3b, the hanging means 5
While supporting the load with a crane or the like through the bolts, the bolts and nuts that previously connected the steel columns 31 of the first layer 3a and the brackets 4 to each other were removed, and a series of first layer that became free
3a and the second layer portion 3b are lowered by operating the crane or the like, and the lower end is sufficiently inserted into the secondary root cutting B, and the upper portion of each steel column 31 of the second layer portion 3b Is removably linked to the brackets 4 with bolts and nuts, and is held in a suspended state. In addition, vertical curing net 37
Temporarily tension. Between the abandoned concrete Bb and the lower end of the first layer portion 3a of the permanent steel staircase 3, a temporary slope pier 6 is stretched over as before. In this way, by temporarily using the first layer portion 3a and the second layer portion 3b of the permanent steel staircase 3, underground construction work of the floor 8, pillars, outer peripheral wall, etc. of the second floor of the basement floor is performed.

(3) Third step (FIG. 3) After the construction of the underground structure of the second floor of the basement, a third root cutting C is performed to fit the construction of the upper half of the third floor of the basement, and the third root cutting bottom. Abandon Ca and hit concrete Cb. However, as mentioned above, because of the design, the floor height of the third basement floor is almost twice as high as that of the first basement floor. It is up to almost half of the floor height. Here, for the reason of workability, the assembling work of the permanent steel staircase 3 on the floor 1 of the ground floor first floor, which is the work floor, is applied to all the rest, that is, the basement first floor and second floor. 3rd layer part
It is assembled as 3c, and is connected and integrated with the upper end of the second layer portion 3b. Of course, the handrail frame temporarily installed at the landing 34 at the upper end of the previous time
15 is useless, so remove it. The structure of each part of the third layer part 3c is also substantially the same as that of the first layer part 3a, but the uppermost steel staircase 33 is formed long from the design standpoint. In this way, the first layer portion 3a to the third layer portion 3c are connected and integrated.
Is lowered in the same manner as the previous time, the lower end is sufficiently inserted into the third root cutting C, and the middle portion of each steel strut 31 of the third layer portion 3c is attached to each bracket 4 with bolts and nuts. Removably linked and held in a suspended state. Further, the temporary tension of the vertical curing net 37 is appropriately extended. Between the abandoned concrete Cb and the lower end of the third layer portion 3c of the permanent steel staircase 3, a temporary free step 9 is passed,
Attach temporary handrail 10. Here, too, the first of the main steel stairs 3
The layer 3a to the third layer 3c are temporarily used to perform an underground skeleton work on the third floor of the basement floor, and the floor is provided with a temporary slab 11 used as a work floor or the like. The temporary slab
11 will eventually be removed.

(4) Fourth step (FIG. 4) After construction of the substructure of the upper half of the third floor of the basement, a fourth root cutting D suitable for construction of the lower half of the third floor of the basement or the foundation slab is performed,
Discard concrete Db at the 4th root cutting Da. Next, the first layer portion 3a to the third layer portion 3c, which are connected and integrated, are lowered in the same manner as the previous time, and the lower end is fully inserted into the fourth root cutting D (in this case, the final installation). Position), the third layer portion 3c
Bolt the upper end of each steel post 31 to each bracket 4 above.
Removably connect with a nut and hold it in a suspended state. Since the foundation slab 12 is provided between the above-mentioned discarded concrete Db and the lower end of the third layer portion 3c of the permanent steel staircase 3, the staircase frame 14 and the handrail frame will be higher than before. A frame scaffold 13 incorporating 15 is provided, and a temporary slope pier 6 is used at the lower end to make up for the shortage. Also, here again, the first layer part 3a to the third layer part 3c of the main steel staircase 3 are temporarily used to carry out the substructure work on the third floor of the basement floor. 12 will be built.

(5) Fifth step (Fig. 5) After construction of the underground skeleton in the lower half of the third floor of the basement floor, that is, after constructing the entire underground skeleton, discard concrete on the foundation slab 12
Hit Dc to fix the lower end of the permanent steel staircase 3 and place the permanent steel staircase 3 at the proper place in the completed underground structure.
Then, the brackets 4 on the floor 1 on the first floor above the ground floor, which had been used for hanging from the beginning, are removed, and the final installation of the permanent steel stairs 3 is completed.

[0011]

EFFECTS OF THE INVENTION According to the present invention, since the main steel staircase on the basement floor is suspended from the preceding work floor and is inserted downward as needed according to the progress of root cutting, it finally reaches the underground structure. The permanent steel stairs to be fixed can be temporarily used for lifting equipment,
Therefore, it is possible to reduce the conventional temporary lifting equipment to unnecessary or very small amount, and to eliminate the trouble of assembling and dismantling the lifting equipment accompanying this, and to construct the conventional steel-frame stairs. Can be eliminated, and the advantages of the reverse driving method can be fully exerted. Moreover, the cost can be significantly reduced. In addition, since the main steel staircase is temporarily used for the lifting equipment in this way, it is possible to improve the convenience and safety of work unlike the temporary lifting equipment.

[Brief description of drawings]

FIG. 1 is a first step explanatory diagram according to an embodiment of a steel frame stair hang-down method of the present invention.

FIG. 2 is an explanatory view of the second step.

FIG. 3 is an explanatory view of the same third step.

FIG. 4 is an explanatory view of the fourth step.

FIG. 5 is an explanatory view of the fifth step.

FIG. 6 is an enlarged plan view of a main part according to the first step explanatory diagram.

[Explanation of symbols]

1 ... Floor on the ground floor 1st floor 2 ... Permanent steel stairway opening 3 ... Permanent steel staircase 31 ... Steel column 32 ... Steel beam 33 ... Steel stair 34 ... Steel landing 35 ... Steel handrail 36 ... Frame reinforcement 37 ... Curing net 4 ... Bracket 5 ... Suspension means 6 ... Slope pier 7 ... Floor on the first basement floor 8 ... Floor on the second floor basement 9 ... Flexible step 10 ... Temporary handrail 11 ... Temporary slab 12 … Basic slab 13… Frame scaffold 14… Staircase frame 15… Handrail frame A… Primary root cutting B… Secondary root cutting C… Third root cutting D… 4th root cutting Aa, Ba, Ca, Da , Dc… Root cutting bottom Ab, Bb, Cb, Db… Abandoned concrete

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical display location E04G 21/14 (72) Inventor Masanobu Hoshi No. 21-1, Ginza Ginza, Chuo-ku, Tokyo Stock company Takenaka Corporation Tokyo Main Store (72) Inventor Ichiro Tomura 21-21 Ginza, Chuo-ku, Tokyo Stock Company Takenaka Corporation Tokyo Main Store (72) Inventor Yasuyuki Shibata 8-21 Ginza, Chuo-ku, Tokyo No. Stock Company Takenaka Corporation Tokyo Main Store

Claims (1)

[Claims] 1. A steel staircase hang-up characterized in that the main steel frame staircase on the basement floor has a structure of suspending from the preceding work floor, and the main steel frame staircase is inserted downward as needed according to the progress of root cutting. Down construction method.