JPH0334533B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for assembling a steel frame for a large roof in the construction of a building having a large interior space, such as a gymnasium, hall, or indoor baseball field.

[Background of the invention]

BACKGROUND ART In buildings that require a large internal space, such as gymnasiums, music halls, and leisure centers, large roofs with trussed steel frames are used. However, as the scale increases, construction requires many very large lifting machines such as tower cranes, and if work is often done at heights, work efficiency is poor and there are dangers involved. Safety equipment will also be important, which will increase the overall construction cost.

In addition, the roof truss can be made into a unit and lifted.
Some methods have been adopted that are said to reduce work at heights, but if a temporary support stand is installed at each joint,
The number of man-hours involved in assembling and dismantling temporary equipment is large.
Furthermore, since the internal working space is limited, an external space for lifting the truss unit from the outside and a tower crane or the like with the corresponding lifting height and lifting capacity are required.

[Purpose of the invention]

This invention was developed to solve the problems in the prior art as described above, and by devising the method and procedure for assembling a large roof steel truss,
The purpose of this project is to make effective use of the internal space and the pre-erected parts, to reduce the size of lifting machines and other machinery used, to improve construction efficiency, and to reduce construction costs.

[Structure of the invention]

In the method of this invention, first the compression ring at the top of the roof and the tension ring at the bottom of the roof are assembled. Compression rings and tension rings are made by assembling steel beams into a circular or polygonal shape.The compression ring at the top bears the axial compression force, and the tension ring forming the bottom edge of the roof carries the roof load. It is designed to bear the axial tensile force exerted by, etc.

Compression rings can be assembled by lifting the steel frame onto a central temporary support platform using a truck crane or other equipment installed inside the construction site.

Next, using an internal truck crane or the like, a plurality of sets of pre-erected parts, each consisting of a pair of large beams and a leading middle truss between the beams, are successively erected between the compression ring and the tension ring. The girder and the leading truss can be divided into units, in which case temporary supports are provided at the joints of the girder. At this time, the space between the preceding construction parts can be used as an installation space for the above-mentioned crane, etc., and a space for assembling the truss unit constituting the roof truss.

In this state, the roof truss is structurally stable for a time, and then the succeeding middle truss that connects the preceding construction parts is erected. This work is carried out using an internally assembled tower crane or an external crane, but since the trailing middle truss can be erected using the preceding construction part, there is no need for temporary supports, etc. There are fewer restrictions on work space, and fewer cranes are required.

Further, a part of the trailing intermediate truss can be constructed from a truss unit assembled on the ground, and can be hoisted to the position where it is connected to the preceding construction part using a winch or the like.

After the roof steel frame is assembled in this way,
The panels that make up the roof surface are sequentially fixed to the steel frame, and the roof is finished.

〔Example〕

Figures 1 to 10 show an example of the construction procedure in the method of assembling a large roof steel frame according to the present invention.
The work is carried out in the following steps.

(1) Assemble the central temporary support stand 9 that supports the top of the large roof and the intermediate temporary support stand 10 on the outer periphery (first
figure).

(2) Assemble the compression ring 1 on the central temporary support stand 9 (Fig. 2). Incidentally, the joint portion 4 of the girder is previously integrally attached to the compression ring 1 at a factory.

(3) Assemble the tension ring 2 on the bottom edge of the roof (Figure 3). At this time, the first section of the divided girder 3 is also assembled at the same time (it is integrated with the tension ring 2 at the factory), and the intermediate temporary support 1
0, and construct the leading intermediate truss 5 between the first sections of the girder 3 as shown in the figure.

(4) Furthermore, install the intermediate temporary support stand 11, and
Add the second section of , and assemble the middle leading middle truss 5' (Figure 4). In this case, the work order of the four preceding construction parts will be determined in relation to parallel work and lifting machinery. It is also desirable to carry out the work as symmetrically as possible so that the load is applied equally to all parts.

(5) Add the third and fourth sections of the girder 3 and connect the compression ring 1 and tension ring 2 (Figure 5). Work efficiency can be improved by assembling the third and fourth sections of the girder 3 in advance and lifting them up using a truck crane or the like.

(6) Perform the work in (5) above for the remaining pre-erected parts (Figure 6).

(7) Complete the erection of the pre-erected part (Figure 7).
Regarding the trailing construction part, the ground assembly of truss unit 7, which will be described later, is progressing in parallel with the work described in (3) below. Additionally, construction of the decorative portion of the roof top 8 and the like will begin.

(8) Regarding the trailing construction section, truss units 7, which are assembled into beams directly below the construction location, are successively installed between the 3 girders (Figure 8). In this case, a frame for hoisting the truss unit is provided in the preceding construction part, and the truss unit can be hoisted up using a winch or the like.

(9) Sequentially erect the truss units 7 and connect the 3 girders in the previously erected section (Figure 9).

(10) Assemble the remaining portion of the truss using a tower crane, etc., and complete the trailing middle truss 6 (Figure 10).

The construction of the steel frame part of the large roof is completed by the above operations (1) to (10).

Figures 11 and 12 show the construction of the preceding construction part, and correspond to the work (6) above. At the point where the second section of the girder 3 is being erected by the truck crane 12, the truss unit 7 is being assembled on a trestle above ground.
Further, a truss hoisting frame 13 for hoisting the truss unit 7 is provided on the girder 3 where the compression ring 1 and the tension ring 2 have already been connected.

FIGS. 13 and 14 show the construction of the trailing intermediate truss 6, and correspond to the operations (8) to (10) described above.

The truss units 7 are successively rolled up using a winch or the like, and then erected between the girders 3 of the previously erected portion. Furthermore, a tower crane 14 is assembled inside to lift the steel frame placed between the erected truss units 7, and the following truss 6 is sequentially assembled.
After the assembly of the tower crane 14 other than the mast part is completed, the tower crane 14 is used for roofing in the subsequent process.
It will be used for installing PC boards, etc., and will be dismantled one by one after the work is completed and removed using an external crawler crane.
In addition, the central temporary support stand 9 and the intermediate temporary support stand 1
0 and 11 will be jacked down, dismantled, and removed after all temporary construction.

Figures 15 and 16 show the state when the roof steel frame has been assembled, and the structure is such that the entire roof truss supports the roof load, and then work is carried out on the roof surface panels or ceiling section.

〔Effect of the invention〕

This invention relates to a method for assembling a steel frame for a large roof, which is constructed as described above, in which a compression ring at the top of the roof and a tension ring at the bottom of the roof are first assembled, and then a medium truss is constructed between a pair of girders. The structure is divided into a leading construction part and a trailing construction part, and the leading construction part of the medium truss installed between the compression ring and the tension ring is used to perform the erection work of the trailing part of the medium truss. Because of this structure, the interior space under the large roof can be effectively used as a work space. In other words, lifting machines such as crawler cranes and tower cranes can be installed in the empty space created in the trailing construction area without the need for temporary supports, etc., and fewer lifting machines can be installed than when installing them outside the large roof. Smaller lifting machines can handle large-scale roof construction.

[Brief explanation of the drawing]

1 to 10 are plan views showing the outline of the construction procedure in an embodiment of the present invention, FIG. 11 is a plan view showing the state of construction of the preceding construction part, FIG. The figure is a plan view showing the construction of the trailing middle truss, Figure 14 is its longitudinal cross-sectional view, and Figure 1
Figure 5 is a plan view when the roof steel frame has been assembled, and Figure 16 is a longitudinal sectional view thereof. 1... compression ring, 2... tension ring, 3... girder, 4... girder joint section, 5... leading truss, 6... trailing truss,
7... Truss unit, 8... Top, 9... Central temporary support stand, 10... Intermediate temporary support stand, 11...
Intermediate temporary support stand, 12...Truck crane, 1
3...Truss hoisting frame, 14...Tower crane.

Claims (1)

[Scope of Claims] 1. First, the compression ring at the top of the roof and the tension ring at the bottom of the roof are assembled, and then, a plurality of sets of the preceding construction portion consisting of a pair of girders and a leading intermediate truss between the girders are assembled. A method for assembling a steel frame for a large roof, characterized in that a trailing intermediate truss is constructed between the compression ring and the tension ring, and then a trailing intermediate truss is constructed to interconnect the preceding construction sections. 2. The method for assembling a steel frame for a large roof as set forth in claim 1, wherein a part of the trailing intermediate truss is constructed of a truss unit assembled on the ground, and is hoisted to the erection position by a winch and erected.