Building construction methods

Abstract

To provide a construction method of building for improving workability and to reduce man-hours.SOLUTION: A construction method of a building having a steel staircase installed in a staircase room and a reinforced concrete skeleton partitioning the staircase room comprises the steps of: installing an internal scaffold in a portion of a predetermined floor in the staircase room; constructing a skeleton of a predetermined floor by using an internal scaffold; removing the internal scaffold installed on the predetermined floor; installing a steel staircase of the predetermined floor; installing a temporary stage functioning as a temporary floor surface of an upper floor of the predetermined floor on the skeleton of the predetermined floor; installing an internal scaffold on a temporary stage; constructing a skeleton of an upper floor by using the internal scaffold; removing the internal scaffold installed on the upper floor, and installing a steel frame staircase of the upper floor.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a construction method for a building. [Background technology]

[0002] The construction method for a reinforced concrete building with a steel staircase installed in a stairwell and a reinforced concrete skeleton (wall) that divides the stairwell is generally as follows: The internal scaffolding is raised from the slab of the lowest floor toward the top floor, while the skeleton is raised, and before the formwork for the slab of the top floor is installed, the internal scaffolding is dismantled down to the slab of the lowest floor. After that, a steel staircase is installed from the lowest floor to the top floor in the space freed up by the dismantling of the internal scaffolding.

[0003] Patent Document 1 also proposes the following method for constructing a reinforced concrete building with a steel staircase. Specifically, the steel staircase side formwork, which forms the surrounding walls of the staircase, is constructed from steel plates, and a steel staircase spanning half a floor is attached to these formwork steel plates as support members, thereby constructing a cylindrical staircase unit with openings at the top and bottom, in which the formwork steel plates are stretched around the steel staircase in a box-like shape. Then, by stacking multiple staircase units, the steel staircase for the staircase is constructed prior to the surrounding walls. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 9-250222 Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-mentioned general construction method, work must be carried out using narrow ascending and descending stairs on the internal scaffolding until the steel staircase is installed from the lowest floor to the top floor, which is not easy to work with. Furthermore, the internal scaffolding must be assembled and dismantled from the lowest floor to the top floor, leaving room for improvement in terms of reducing labor hours. Furthermore, after the internal scaffolding is dismantled, a deep vertical hole is created before the steel staircase is installed, leaving room for improvement in terms of work safety. Furthermore, the construction method described in the above-mentioned Patent Document 1 requires the fabrication and installation of a staircase unit made of steel formwork plates stretched in a box shape around the steel staircase, which also makes workability poor.

[0006] This specification discloses a technique that can solve at least part of the above-mentioned problems. [Means for solving the problem]

[0007] The technology disclosed in this specification can be realized, for example, in the following forms.

[0008] (1) The present specification discloses a method for constructing a building made of reinforced concrete, the building having a steel staircase installed in a staircase and a reinforced concrete skeleton that defines the staircase. The method includes the steps of: installing internal scaffolding in a portion of the staircase on a predetermined floor; constructing the skeleton of the predetermined floor using the internal scaffolding; removing the internal scaffolding installed on the predetermined floor; installing the steel staircase on the predetermined floor; installing a temporary stage on the skeleton of the predetermined floor to serve as a temporary floor for the floor above the predetermined floor; installing the internal scaffolding on the temporary stage; constructing the skeleton of the upper floor using the internal scaffolding; removing the internal scaffolding installed on the upper floor; and installing the steel staircase on the upper floor.

[0009] According to this building construction method, the steel staircase for a given floor is installed immediately after the framework of that floor is constructed, allowing that floor to be used as a work staircase thereafter, improving workability. Furthermore, it is only necessary to set up the internal scaffolding for one floor and then install and remove it using a crawler crane or similar device, thereby reducing the number of steps compared to conventional construction methods in which the internal scaffolding is assembled and dismantled from the lowest floor to the top floor. Furthermore, because the steel staircase is installed immediately after the internal scaffolding is removed for each floor, the need for stairwell curing can be omitted, further reducing work hours. In this way, this building construction method achieves improved workability and reduced work hours.

[0010] (2) In the above-mentioned building construction method, each of the steps may be configured to be performed repeatedly starting from the lowest floor and until the installation of the steel frame staircase on the top floor is completed. This building construction method can effectively improve workability and reduce labor costs throughout the entire construction from the lowest floor to the top floor.

[0011] The technology disclosed in this specification can be realized in various forms, for example, in the form of a construction method for a building, a method for installing a steel staircase, a building or steel staircase manufactured by these methods, etc. [Brief explanation of the drawings]

[0012] [Figure 1] An explanatory diagram showing the configuration of a building 100 in this embodiment. [Figure 2] Flowchart showing the construction method of the building 100 [Figure 3] An explanatory diagram showing a schematic construction method of the building 100. [Figure 4] An explanatory diagram showing a schematic construction method of the building 100. [Figure 5] An explanatory diagram showing a schematic construction method of the building 100. [Figure 6] An explanatory diagram showing a schematic construction method of the building 100. DETAILED DESCRIPTION OF THE INVENTION

[0013] A. Implementation: A-1. Structure of Building 100: FIG. 1 is an explanatory diagram showing the configuration of a building 100 in this embodiment. The building 100 is a reinforced concrete building. In this embodiment, the building 100 has four or more floors, but floors above the fourth floor are not shown in FIG. 1. The building 100 has a steel frame staircase 20, a skeleton 10, and a slab 30.

[0014] The steel staircase 20 is a steel-framed staircase installed in a staircase S1 in a building 100. In this embodiment, the steel staircase 20 is a return-type staircase with an intermediate landing. The skeleton 10 is a rising skeleton (wall) made of reinforced concrete that divides the staircase S1. The skeleton 10 has openings for accessing the staircase S1. The slab 30 is a skeleton made of reinforced concrete that forms the floor of each floor.

[0015] A-2. Construction method of Building 100: FIG. 2 is a flowchart showing a construction method for the building 100. Also, FIGS. 3 to 6 are explanatory diagrams that schematically show the construction method for the building 100. Below, the construction method for the vicinity of the staircase S1 in the building 100 will be explained. Note that in the construction method for the building 100 of this embodiment, work is carried out floor by floor, from the lowest floor (the first floor in this embodiment) to the top floor. In the following explanation, the number of floors under construction will be referred to as "construction floor N."

[0016] First, construction begins on the first floor, which is the lowest floor (construction floor N=1, S110). Specifically, the internal scaffolding 202 is installed in the first floor portion of the staircase S1 (S120). In this embodiment, the internal scaffolding 202 is installed on the floor of the first floor. Furthermore, the height of the internal scaffolding 202 is set to be slightly higher than the floor height. Therefore, the upper end of the internal scaffolding 202 installed on the first floor portion is located slightly above the floor surface of the second floor. The internal scaffolding 202 can be created by assembling scaffolding materials. The internal scaffolding 202 may be assembled within the staircase S1, or may be assembled in another location and transported to the staircase S1.

[0017] Next, using the internal scaffolding 202 installed on the first floor of the staircase S1, structural work is carried out to construct the first floor structural body 10 (S130). The structural work includes, for example, the steps of assembling formwork, arranging reinforcement, pouring concrete, etc. Fig. 3 shows the state in which the internal scaffolding 202 has been installed on the first floor and the structural work to construct the first floor structural body 10 using this internal scaffolding 202 has been completed.

[0018] Next, the formwork for constructing the first-floor skeleton 10 is dismantled, and stair support members are attached. Thereafter, the internal scaffolding 202 installed on the first floor is removed (S140). The internal scaffolding 202 is removed by, for example, hoisting it with a crawler crane or the like and transporting it to a location other than the staircase S1. Then, the steel staircase 20 for the first floor is installed in the first-floor portion of the staircase S1 (S150). The installed steel staircase 20 is fixed to the stair support members. The steel staircase 20 is installed by, for example, hoisting it with a crawler crane or the like and transporting it into the staircase S1. FIG. 4 shows the state in which the internal scaffolding 202 installed on the first-floor portion of the staircase S1 has been removed, and the steel staircase 20 (20a) has been installed in the space on the first floor that has become vacant. From this point on, the steel staircase 20 (20a) on the first floor can be used as a work staircase.

[0019] Thereafter, the construction method for the building 100 branches depending on whether construction on an upper floor is required (S160). If construction on an upper floor is required (S160: YES), the construction floor N is incremented by one (N=N+1, S170). For example, after the steel staircase 20 is installed on the first floor, the construction floor N is set to the second floor.

[0020] When constructing the second floor, a temporary stage 204 that functions as a temporary floor for the second floor is installed on the skeleton 10 of the lower floor (first floor) (S180). The temporary stage 204 can be created, for example, by laying scaffolding boards on a Peko beam, either via floor joists or directly. After that, the process returns to S120, and the internal scaffolding 202 is installed in the second floor portion of the staircase S1 (S120). For the second floor and above, the internal scaffolding 202 is installed on the temporary stage 204 described above. Then, using the installed internal scaffolding 202, skeleton work is carried out to build the skeleton 10 of the second floor (S130). Figure 5 shows the completed state of the structural work, in which a temporary stage 204 that functions as a temporary floor surface for the second floor in the stairwell S1 has been installed, an internal scaffolding 202 has been installed on the temporary stage 204, and the internal scaffolding 202 installed on the second floor has been used to construct the second floor structure 10.

[0021] Thereafter, as in the above, the formwork for constructing the second-floor skeleton 10 is dismantled, stair support members are installed, and then the internal scaffolding 202 installed on the second floor is removed (S140). At this time, if construction is being carried out on the second floor or above, the temporary stage 204 is also removed. Then, the steel staircase 20 for the second floor is installed in the second floor portion of the staircase S1 (S150). Figure 6 shows the state in which the internal scaffolding 202 installed on the second floor portion of the staircase S1 has been removed, and the steel staircase 20 (20b) has been installed in the space on the second floor that has become vacant. From this point on, the steel staircases 20 (20a, 20b) on the first and second floors can be used as work stairs.

[0022] These steps are repeated until the installation of the steel staircase 20 on the top floor (S150) is completed, and no further construction work is required on the upper floors (S160: NO). At this time, the construction of the building 100 is completed after the remaining steps, such as the installation of the slab on the top floor, are completed.

[0023] A-3. Advantages of this embodiment: As described above, the construction method for the building 100 of this embodiment includes the steps of installing the internal scaffolding 202 in a portion of the staircase S1 on a predetermined floor, constructing the structure 10 of the predetermined floor using the internal scaffolding 202, removing the internal scaffolding 202 installed on the predetermined floor, installing the steel staircase 20 on the predetermined floor, installing a temporary stage 204 on the structure 10 of the predetermined floor to function as a temporary floor surface for the floor above the predetermined floor, installing the internal scaffolding 202 on the temporary stage 204, constructing the structure 10 of the upper floor using the internal scaffolding 202, removing the internal scaffolding 202 installed on the upper floor, and installing the steel staircase 20 on the upper floor.

[0024] As described above, in the construction method for the building 100 of this embodiment, the steel staircase 20 for a certain floor is installed immediately after the skeleton 10 of that floor is constructed. Therefore, the steel staircase 20 can be used as a work staircase thereafter, improving workability. Furthermore, since it is only necessary to assemble the internal scaffolding 202 for one floor and then install and remove it using a crawler crane or the like, labor hours can be reduced compared to conventional construction methods in which internal scaffolding is assembled and dismantled from the lowest floor to the top floor. Furthermore, because the steel staircase 20 is installed immediately after the internal scaffolding 202 is removed for each floor, the need for void curing can be omitted, further reducing labor hours. Thus, the construction method for the building 100 of this embodiment can improve workability and reduce labor hours.

[0025] Furthermore, in the construction method for the building 100 of this embodiment, the above steps are repeated starting from the lowest floor until the installation of the steel staircase 20 on the top floor is completed. Therefore, it is possible to effectively improve workability and reduce the number of steps throughout the entire construction from the lowest floor to the top floor.

[0026] B. Variations: The technology disclosed in this specification is not limited to the above-described embodiments, and can be modified into various forms without departing from the spirit thereof, for example, the following modifications are also possible.

[0027] The configuration of the building 100 in the above embodiment is merely an example and can be modified in various ways. For example, in the above embodiment, the building 100 is four or more stories high, but the building 100 may be three or less stories high.

[0028] In the above embodiment, the steel staircase 20 is a return staircase having an intermediate landing, but the steel staircase 20 may be a straight staircase without an intermediate landing.

[0029] The construction method of the building 100 in the above embodiment is merely an example and can be modified in various ways. For example, in the above embodiment, the above-described steps are repeatedly performed on all floors of the building 100, but the above-described steps may be repeatedly performed on some floors of the building 100 (however, on multiple consecutive floors). [Explanation of symbols]

[0030] 10: Structure 20: Steel staircase 30: Slab 100: Building 202: Internal scaffolding 204: Temporary stage S1: Staircase

Claims

1. A construction method for a reinforced concrete building having a steel frame staircase installed in a staircase and a reinforced concrete skeleton that divides the staircase, A step of installing an internal scaffolding at a portion of the stairwell on a predetermined floor; constructing the skeleton of the predetermined floor using the internal scaffolding; A step of removing the internal scaffolding installed on the predetermined floor; a step of installing the steel staircase on the predetermined floor; a step of installing a temporary stage on the frame of the predetermined floor, the temporary stage functioning as a temporary floor surface for the floor above the predetermined floor; Installing the internal scaffolding on the temporary stage; constructing the framework of the upper floor using the internal scaffolding; A step of removing the internal scaffolding installed on the upper floor; a step of installing the steel staircase on the upper floor; A construction method for a building comprising:

2. The construction method for a building according to claim 1, A method for constructing a building, wherein each of the steps is repeated starting from the lowest floor and until installation of the steel frame staircase on the top floor is completed.

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