Reverse punching manufacturing process of earthenware brick and GRC integrated plate curtain wall system

Abstract

The invention relates to the technical field of curtain walls, in particular to a reverse punching manufacturing process of a ceramic brick and GRC integrated plate curtain wall system. The method comprises the following steps: firstly, preparing a silica gel mold with a plurality of grooves in a demolding side, placing the silica gel mold in a glass fiber reinforced plastic mold, and keeping the demolding side exposed; then putting the earthenware brick into the groove of the silica gel mold; uniformly stirring and mixing quartz sand, cement, water and the GRC adhesive cement emulsion solution to obtain GRC slurry, spraying the GRC slurry on the demolding side of the silica gel mold by using a spray gun, and sequentially carrying out rolling, edge closing, demolding and maintenance treatment to obtain a GRC substrate; and finally, steel frames are arranged on the side, away from the earthenware bricks, of the GRC base plate at intervals, and the earthenware brick and GRC integrated plate curtain wall is obtained. The earthenware bricks and the GRC base plate are both subjected to factory standardization and mold reverse mold prefabrication processing, environmental protection is achieved, pollution is reduced, the earthenware brick pasting quality problem is solved, the earthenware brick stripping problem is also solved, and the method can be applied to outer walls of newly-built, rebuilt and expanded high-rise and super high-rise buildings.

Description

Technical Field

[0001] The invention relates to the technical field of curtain walls, and in particular to a reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system. Background Art

[0002] Traditional building brick walls are built by construction masons one by one by hand, but they have the following disadvantages: 1) The quality of masonry or tiling is basically determined by the workers' craftsmanship, and the quality of different workers is different, and the quality is relatively unstable; 2) Moreover, the construction efficiency of traditional masonry or tiling technology is relatively low, time-consuming, and requires on-site maintenance; 3) When working at high altitudes, due to the poor construction conditions of the workers, the construction quality is even more uncontrollable, and there is a risk of tiles falling off; that is, traditional workers' manual tiling cannot be applied to high-rise buildings, and there is a risk of falling from a height.

[0003] Therefore, it is crucial to provide ceramic brick and GRC integrated panel curtain wall. Summary of the invention

[0004] In order to solve the above problems, the purpose of the present invention is to provide a reverse-beating production process for a ceramic tile and GRC integrated panel curtain wall system. The present invention first prepares a silicone mold containing a plurality of grooves on the demoulding side, places the silicone mold in a glass fiber reinforced plastic mold, and keeps the demoulding side exposed; then places the ceramic tile into the groove of the silicone mold; stirs and mixes quartz sand, cement, water and GRC mortar emulsion solution to obtain GRC slurry, and uses a spray gun to spray the GRC slurry on the demoulding side of the silicone mold, and then performs rolling, edge trimming, demoulding, and curing treatment in sequence to obtain a GRC substrate; finally, a steel frame is set at intervals on the side of the GRC substrate away from the ceramic tile to obtain a ceramic tile and GRC integrated panel curtain wall. In the present invention, both the ceramic tile and the GRC substrate are standardized in the factory, and the mold is reversed and prefabricated, which is green and environmentally friendly and reduces pollution. It not only solves the quality problem of ceramic tile pasting, but also solves the problem of ceramic tile peeling, and can be applied to the exterior walls of new, rebuilt and expanded high-rise and super high-rise buildings.

[0005] The reverse-beating production process of the ceramic brick and GRC integrated panel curtain wall system provided by the present invention utilizes a silicone mold and a glass fiber reinforced plastic mold in combination, and does not require the application of a release agent during production demoulding, thereby not polluting the GRC product.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] The present invention provides a reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system, comprising the following steps:

[0008] (S1) preparing a silicone mold with a plurality of grooves on the demoulding side, placing the silicone mold in a fiberglass mold, and keeping the demoulding side exposed;

[0009] (S2) placing the ceramic brick into the groove of the silicone mold prepared in step (S1);

[0010] (S3) After step (S2), quartz sand, cement, water and GRC mortar emulsion solution are stirred and mixed to obtain GRC slurry, and the GRC slurry is sprayed on the demoulding side of the silicone mold by a spray gun, and rolling, edge trimming, demoulding and curing are performed in sequence to obtain a GRC substrate;

[0011] (S4) After step (S3) is completed, a steel frame is provided at intervals on a side of the GRC substrate away from the ceramic tiles to obtain a ceramic tile and GRC integrated panel curtain wall.

[0012] In the present invention, a ceramic tile groove is carved out by a numerically controlled engraving machine, and is molded with a silicone film to obtain a silicone mold containing a ceramic tile groove; wherein the groove can be processed according to the required ceramic tile arrangement;

[0013] Use CNC machine tools to make wooden or plaster positive molds according to the drawings, and use resin to mold the FRP mold; ensure that the FRP mold matches the silicone mold;

[0014] In one embodiment of the present invention, in step (S1), the spacing between adjacent ceramic tile grooves is 200 mm to 600 mm;

[0015] The details of CNC engraving machine engraving are as follows: According to the requirements of the engineering design drawings and the facade effects, the production of GRC products requires a two-in-one silicone mold and a fiberglass mold for processing; the factory technicians input the drawing numbers into the CNC engraving machine to carve out the ceramic tile grooves, and use silicone molds to form them.

[0016] The fiberglass mold is made by mold workers using CNC machine tools to carve out the pallet according to the size of the drawing, and then piling up plaster to pull out the shape little by little; until the surface is smooth and flawless, they begin to use resin to mold it.

[0017] In one embodiment of the present invention, in step (S3), the mass ratio of quartz sand, cement, water and GRC mortar emulsion is 34% to 51%: 34% to 51%: 11% to 17%: 1.5% to 2%;

[0018] The sum of the mass ratios of quartz sand, cement, water and GRC mortar emulsion is 100%.

[0019] In one embodiment of the present invention, the mass ratio of quartz sand, cement, water and GRC mortar emulsion is 35%:51%:12%:2%.

[0020] In one embodiment of the present invention, in step (S3), during the spraying process, a coaxial continuous spraying device is used, and the spraying is performed in layers in a horizontal and vertical cross-spraying manner.

[0021] In one embodiment of the present invention, in step (S3), the spraying thickness of the GRC slurry needs to ensure that the thickness of the GRC substrate is 15 mm to 20 mm.

[0022] In one embodiment of the present invention, in step (S3), during the rolling process, the rolling hand and the spray gun operator cooperate (which can improve efficiency and evenly compact the rolling in place);

[0023] During the trimming process (requirements: keep straight line, smooth appearance, clean back), the thickness of the trimming corner is kept at 28mm to 32mm; preferably, the thickness of the trimming corner is 30mm;

[0024] After the edge is trimmed, it will generally reach the required strength after being placed at room temperature for 12 hours, and can be demoulded;

[0025] The curing is selected from conventional curing or steam curing, and the curing period is 3 to 7 days.

[0026] In one embodiment of the present invention, in step (S4), the steel frame and the GRC substrate are connected by hot-dip galvanized round steel with a diameter of 8 mm to 12 mm;

[0027] Preferably, the diameter of the hot-dip galvanized round steel is 10 mm.

[0028] In one embodiment of the present invention, in step (S4), the spacing between adjacent steel frames is set to be less than 600 mm.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) The present invention provides a new manufacturing process for bonding and integrally forming a GRC substrate and ceramic tiles, which can be assembled and installed as a whole at the construction site, with relatively high construction efficiency and construction accuracy, which can greatly save construction time and shorten the project period;

[0031] (2) The ceramic tiles and GRC substrates in the present invention are standardized in the factory and prefabricated by mold casting, which not only solves the problem of ceramic tile pasting quality, but also solves the problem of ceramic tile peeling, and can be applied to the exterior walls of new construction, reconstruction and expansion of high-rise and super high-rise buildings. DETAILED DESCRIPTION

[0032] The present invention is described in detail below with reference to specific embodiments.

[0033] In the following embodiments, the size of the groove matches the size of the ceramic tile, ensuring that the ceramic tile fits exactly into the groove.

[0034] In the following examples, unless otherwise specified, all reagents used are commercially available reagents, and all detection means and methods used are conventional detection means and methods in the art.

[0035] Example 1

[0036] This embodiment provides a reverse-beating manufacturing process of a ceramic tile and GRC integrated panel curtain wall system, which specifically includes the following steps:

[0037] (S1) preparing a silicone mold with a plurality of grooves on the demoulding side to prepare a glass fiber reinforced plastic mold;

[0038] Among them, a ceramic tile groove is carved out by a CNC engraving machine, and a silicone film is used to form a silicone mold containing a ceramic tile groove;

[0039] According to the drawings, a wooden or plaster positive mold is made using a CNC machine tool, and then a fiberglass mold is obtained by using resin to cast the mold;

[0040] (S2) placing the silicone mold in the fiberglass mold with the demoulding side exposed;

[0041] (S3) placing the ceramic brick into the groove of the silicone mold prepared in step (S1);

[0042] (S4) After step (S3) is completed, quartz sand, cement, water and GRC mortar emulsion are stirred and mixed (wherein, the mass ratio of quartz sand, cement, water and GRC mortar emulsion is 41%:43%:15.2%:1.8%) to obtain GRC slurry, and the GRC slurry is sprayed on the demoulding side of the silicone film by a spray gun (coaxial continuous spraying equipment is used, and the spraying is layered by horizontal and vertical cross spraying), and rolling, edge trimming, demoulding, and steam curing are performed in sequence for 5 days to obtain a GRC substrate with a thickness of 18 mm (the thickness of the ceramic brick embedded in the GRC substrate is 8 mm);

[0043] During the rolling process, the rolling hand and the spray gun operator cooperate with each other (which can improve efficiency and compact the surface evenly after rolling into place); the thickness of the edge corner is maintained at 30mm during the edge finishing process; after the edge finishing is completed, it is placed at room temperature for 12 hours before demoulding.

[0044] (S5) After step (S4) is completed, a steel frame is provided at intervals on the side of the GRC substrate away from the ceramic bricks (connected by hot-dip galvanized round steel with a diameter of 10 mm, and the spacing between adjacent steel frames is 450 mm), to obtain a ceramic brick and GRC integrated panel curtain wall;

[0045] The bonding strength between the ceramic brick and the GRC substrate in the ceramic brick and GRC integrated panel curtain wall system prepared in this embodiment is 7.0 MPa, and the construction accuracy is ±0.5 mm.

[0046] Example 2

[0047] This embodiment provides a reverse-beating manufacturing process of a ceramic tile and GRC integrated panel curtain wall system, which specifically includes the following steps:

[0048] (S1) preparing a silicone mold with a plurality of grooves on the demoulding side to prepare a glass fiber reinforced plastic mold;

[0049] Among them, a ceramic tile groove is carved out by a CNC engraving machine, and a silicone film is used to form a silicone mold containing a ceramic tile groove;

[0050] According to the drawings, a wooden or plaster positive mold is made using a CNC machine tool, and then a fiberglass mold is obtained by using resin to cast the mold;

[0051] (S2) placing the silicone mold in the fiberglass mold with the demoulding side exposed;

[0052] (S3) placing the ceramic brick into the groove of the silicone mold prepared in step (S1);

[0053] (S4) After step (S3) is completed, quartz sand, cement, water and GRC mortar emulsion are stirred and mixed (wherein, the mass ratio of quartz sand, cement, water and GRC mortar emulsion is 34%:47.5%:17%:1.5%) to obtain GRC slurry, and the GRC slurry is sprayed on the demoulding side of the silicone film by a spray gun (coaxial continuous spraying equipment is used, and the spraying is layered by horizontal and vertical cross spraying). Rolling, edge trimming, demoulding, and steam curing are performed in sequence for 3 days to obtain a GRC substrate with a thickness of 15 mm (the thickness of the ceramic brick embedded in the GRC substrate is 7 mm);

[0054] During the rolling process, the rolling hand and the spray gun operator cooperate (to improve efficiency and evenly compact the rolling in place); the thickness of the edge corner is maintained at 32mm during the edge finishing process; after the edge finishing is completed, it is placed at room temperature for 12 hours before demoulding;

[0055] (S5) After step (S4) is completed, steel frames are arranged at intervals on the side of the GRC substrate away from the ceramic tiles (connected by hot-dip galvanized round steel with a diameter of 8 mm, and the spacing between adjacent steel frames is 500 mm) to obtain a ceramic tile and GRC integrated panel curtain wall.

[0056] The bonding strength between the ceramic bricks and the GRC substrate in the ceramic brick and GRC integrated panel curtain wall system prepared in this embodiment is 8.1 MPa, and the construction accuracy is ±0.3 mm.

[0057] Example 3

[0058] This embodiment provides a reverse-beating manufacturing process of a ceramic tile and GRC integrated panel curtain wall system, which specifically includes the following steps:

[0059] (S1) preparing a silicone mold with a plurality of grooves on the demoulding side to prepare a glass fiber reinforced plastic mold;

[0060] Among them, a ceramic tile groove is carved out by a CNC engraving machine, and a silicone film is used to form a silicone mold containing a ceramic tile groove;

[0061] According to the drawings, a wooden or plaster positive mold is made using a CNC machine tool, and then a fiberglass mold is obtained by using resin to cast the mold;

[0062] (S2) placing the silicone mold in the fiberglass mold with the demoulding side exposed;

[0063] (S3) placing the ceramic brick into the groove of the silicone mold prepared in step (S1);

[0064] (S4) After step (S3) is completed, quartz sand, cement, water and GRC mortar emulsion are stirred and mixed (wherein, the mass ratio of quartz sand, cement, water and GRC mortar emulsion is 51%:34%:13%:2%) to obtain GRC slurry, and the GRC slurry is sprayed on the demoulding side of the silicone film by a spray gun (coaxial continuous spraying equipment is used, and the spraying is layered by horizontal and vertical cross spraying), and rolling, edge trimming, demoulding, and steam curing are performed in sequence for 7 days to obtain a GRC substrate with a thickness of 20 mm (the thickness of the ceramic brick embedded in the GRC substrate is 9 mm);

[0065] During the rolling process, the rolling hand and the spray gun operator cooperate with each other (which can improve efficiency and compact the surface evenly after rolling into place); the thickness of the edge corner is maintained at 28mm during the trimming process; after the trimming is completed, it is placed at room temperature for 12 hours before demolding.

[0066] (S5) After step (S4) is completed, steel frames are arranged at intervals on the side of the GRC substrate away from the ceramic tiles (connected by hot-dip galvanized round steel with a diameter of 12 mm, and the spacing between adjacent steel frames is 400 mm) to obtain a ceramic tile and GRC integrated panel curtain wall.

[0067] In the ceramic tile and GRC integrated panel curtain wall system prepared in this embodiment, the bonding strength between the ceramic tile and the GRC substrate is 7.8 MPa, and the construction accuracy is ±0.4 mm.

[0068] Example 4

[0069] This embodiment provides a reverse-beating manufacturing process of a ceramic tile and GRC integrated panel curtain wall system, which specifically includes the following steps:

[0070] (S1) preparing a silicone mold with a plurality of grooves on the demoulding side to prepare a glass fiber reinforced plastic mold;

[0071] Among them, a ceramic tile groove is carved out by a CNC engraving machine, and a silicone film is used to form a silicone mold containing a ceramic tile groove;

[0072] According to the drawings, a wooden or plaster positive mold is made using a CNC machine tool, and then a fiberglass mold is obtained by using resin to cast the mold;

[0073] (S2) placing the silicone mold in the fiberglass mold with the demoulding side exposed;

[0074] (S3) placing the ceramic brick into the groove of the silicone mold prepared in step (S1);

[0075] (S4) After step (S3) is completed, quartz sand, cement, water and GRC mortar emulsion are stirred and mixed (wherein, the mass ratio of quartz sand, cement, water and GRC mortar emulsion is 35%:51%:12%:2%) to obtain GRC slurry, and the GRC slurry is sprayed on the demoulding side of the silicone film by a spray gun (coaxial continuous spraying equipment is used, and the spraying is layered by horizontal and vertical cross spraying), and rolling, edge finishing, demoulding, and steam curing are performed in sequence for 5 days to obtain a GRC substrate with a thickness of 18 mm (the thickness of the ceramic brick embedded in the GRC substrate is 8 mm);

[0076] During the rolling process, the rolling hand and the spray gun operator cooperate with each other (which can improve efficiency and compact the surface evenly after rolling into place); the thickness of the edge corner is maintained at 30mm during the edge finishing process; after the edge finishing is completed, it is placed at room temperature for 12 hours before demoulding.

[0077] (S5) After step (S4) is completed, steel frames are arranged at intervals on the side of the GRC substrate away from the ceramic tiles (connected by hot-dip galvanized round steel with a diameter of 10 mm, and the spacing between adjacent steel frames is 450 mm) to obtain a ceramic tile and GRC integrated panel curtain wall.

[0078] The bonding strength between the ceramic bricks and the GRC substrate in the ceramic brick and GRC integrated panel curtain wall system prepared in this embodiment is 8.9 MPa, and the construction accuracy is ±0.5 mm.

[0079] Example 5

[0080] This embodiment provides a reverse-beating manufacturing process of a ceramic tile and GRC integrated panel curtain wall system, which specifically includes the following steps:

[0081] (S1) preparing a silicone mold with a plurality of grooves on the demoulding side to prepare a glass fiber reinforced plastic mold;

[0082] Among them, a ceramic tile groove is carved out by a CNC engraving machine, and a silicone film is used to form a silicone mold containing a ceramic tile groove;

[0083] According to the drawings, a wooden or plaster positive mold is made using a CNC machine tool, and then a fiberglass mold is obtained by using resin to cast the mold;

[0084] (S2) placing the silicone mold in the fiberglass mold with the demoulding side exposed;

[0085] (S3) placing the ceramic brick into the groove of the silicone mold prepared in step (S1); (S4) after step (S3), stirring and mixing quartz sand, cement, water and GRC mortar emulsion (wherein the mass ratio of quartz sand, cement, water and GRC mortar emulsion is 34.5%:51%:13%:1.5%) to obtain GRC slurry, and spraying the GRC slurry on the demoulding side of the silicone film with a spray gun (using a coaxial continuous spraying device and spraying in layers by a horizontal and vertical cross-spraying method), rolling, edge trimming, demoulding, and steam curing for 5 days in sequence to obtain a GRC substrate with a thickness of 18 mm (the thickness of the ceramic brick embedded in the GRC substrate is 8 mm);

[0086] During the rolling process, the rolling hand and the spray gun operator cooperate with each other (which can improve efficiency and compact the surface evenly after rolling into place); the thickness of the edge corner is maintained at 30mm during the edge finishing process; after the edge finishing is completed, it is placed at room temperature for 12 hours before demoulding.

[0087] (S5) After step (S4) is completed, steel frames are arranged at intervals on the side of the GRC substrate away from the ceramic tiles (connected by hot-dip galvanized round steel with a diameter of 10 mm, and the spacing between adjacent steel frames is 450 mm) to obtain a ceramic tile and GRC integrated panel curtain wall.

[0088] In the ceramic tile and GRC integrated panel curtain wall system prepared in this embodiment, the bonding strength between the ceramic tile and the GRC substrate is 7.2 MPa, and the construction accuracy is ±0.3 mm.

[0089] Comparative Example 1

[0090] This comparative example provides a ceramic tile and GRC integrated panel curtain wall system. Compared with Example 1, the ceramic tile is bonded to the GRC substrate. (Non-reverse process)

[0091] Quartz sand, cement, water and GRC mortar emulsion are stirred and mixed (wherein, the mass ratio of quartz sand, cement, water and GRC mortar emulsion is 34.5%:51%:13%:1.5%) to obtain GRC slurry, and the GRC slurry is sprayed with a spray gun (coaxial continuous spraying equipment is used, and the GRC slurry is sprayed in layers by horizontal and vertical cross-spraying), and rolling, edge trimming, demoulding, and steam curing are performed in sequence for 5 days to obtain a GRC substrate with a thickness of 18 mm (wherein, ensure that a groove for accommodating ceramic tiles is reserved on the GRC substrate, and the depth of the groove is 8 mm (that is, the thickness of the ceramic tiles embedded in the GRC substrate is 8 mm));

[0092] During the rolling process, the rolling hand and the spray gun operator cooperate with each other (which can improve efficiency and compact the surface evenly after rolling into place); the thickness of the edge corner is maintained at 30mm during the edge finishing process; after the edge finishing is completed, it is placed at room temperature for 12 hours before demoulding.

[0093] Then, the ceramic tiles are laid in the grooves of the GRC substrate through polyurethane emulsion, and steel frames are arranged at intervals on the side of the GRC substrate away from the ceramic tiles (connected by hot-dip galvanized round steel with a diameter of 10 mm, and the spacing between adjacent steel frames is 450 mm) to obtain a ceramic tile and GRC integrated panel curtain wall.

[0094] In the ceramic brick and GRC integrated panel curtain wall system prepared in this comparative example, the average bonding strength between the ceramic brick and the GRC substrate is 0.6 MPa, and the construction accuracy is ±2 mm.

[0095] Through comparative example 1 and example 1, it can be found that the ceramic brick and GRC integrated panel curtain wall system prepared in example 1 has relatively high construction efficiency and construction accuracy, and the ceramic brick is not easy to peel off, and can be applied to the exterior walls of new construction, reconstruction and expansion of high-rise and super high-rise buildings.

[0096] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the explanation of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A reverse-beating manufacturing process for a ceramic brick and GRC integrated panel curtain wall system, characterized in that: The following steps are involved: (S1) preparing a silicone mold with a plurality of grooves on the demoulding side, placing the silicone mold in a fiberglass mold, and keeping the demoulding side exposed; (S2) placing the ceramic brick into the groove of the silicone mold prepared in step (S1); (S3) After step (S2), quartz sand, cement, water and GRC mortar emulsion solution are stirred and mixed to obtain GRC slurry, and the GRC slurry is sprayed on the demoulding side of the silicone mold by a spray gun, and rolling, edge trimming, demoulding and curing are performed in sequence to obtain a GRC substrate; (S4) After step (S3) is completed, a steel frame is provided at intervals on a side of the GRC substrate away from the ceramic tiles to obtain a ceramic tile and GRC integrated panel curtain wall.

2. The reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system according to claim 1 is characterized in that: In step (S1), the spacing between adjacent ceramic tile grooves is 200 mm to 600 mm.

3. The reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system according to claim 1 is characterized in that: In step (S3), the mass ratio of quartz sand, cement, water and GRC mortar emulsion is 34% to 51%: 34% to 51%: 11% to 17%: 1.5% to 2%; The sum of the mass ratios of quartz sand, cement, water and GRC mortar emulsion is 100%.

4. The reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system according to claim 1 is characterized in that: In step (S3), during the spraying process, a horizontal and vertical cross spraying method is adopted, and the spraying is carried out in layers.

5. The reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system according to claim 1 is characterized in that: In step (S3), during the rolling process, the rolling hand and the spray gun operating hand cooperate with each other.

6. The reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system according to claim 1 is characterized in that: In step (S3), during the edge trimming process, the thickness of the edge trimming corner is maintained at 28 mm to 32 mm.

7. The reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system according to claim 1 is characterized in that: In step (S3), the curing is selected from conventional curing or steam curing.

8. The reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system according to claim 1 is characterized in that: In step (S3), the thickness of the GRC substrate is 15 mm to 20 mm.

9. The reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system according to claim 1 is characterized in that: In step (S4), the steel frame and the GRC substrate are connected via hot-dip galvanized round steel with a diameter of 8 mm to 12 mm.

10. The reverse-beating manufacturing process of a ceramic brick and GRC integrated panel curtain wall system according to claim 1 is characterized in that: In step (S4), the spacing between adjacent steel frames is set to be less than 600 mm.