Prefabricated buildings and construction methods

Abstract

The present invention relates to an assembled building, comprising a main frame structure formed by steel columns and steel beams, a wall body formed by integral prefabricated wall panels, and a floor slab formed by integral prefabricated floor slabs, wherein the integral prefabricated wall panels include prefabricated exterior wall panels and prefabricated interior wall panels; the steel columns and steel beams are hot-rolled seamless special-shaped steel pipes, which are connected to each other by node plates and bolts; the steel columns are arranged between adjacent prefabricated wall panels, and wet joints are arranged between the steel columns and the end faces of the prefabricated wall panels; the outer peripheral surfaces of the steel columns are buried in the wet joints or part of the outer peripheral surfaces are flush with the surface of the prefabricated wall panels; the prefabricated exterior wall panels adopt the method of "external wall hanging, internal wall embedding", the exterior wall is a "sandwich" structure with internal and external decoration and insulation, the interior wall is a hollow high-strength lightweight concrete, and the floor slab is an integral two-way double-layer prestressed concrete hollow slab structure. The invention forms a building structure with good overall assembly, simple process flow, firm structure and good earthquake resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of prefabricated buildings, and in particular to a prefabricated building and a construction method. Background Art

[0002] At present, the implementation of prefabricated buildings is the general trend and the need for social, political and economic development. The proportion of prefabricated industrialized housing in Sweden accounts for 80%, and the United Kingdom, the United States and Japan are all above 70%. However, in China, where the construction volume accounts for 50% of the world, this ratio is less than 7%.

[0003] The development of prefabricated housing can improve common quality problems such as structural accuracy, leakage, cracking, etc., improve sound insulation, thermal insulation, fire prevention and other performance, and facilitate system maintenance and updating. Prefabricated housing has a huge energy-saving and emission-reduction effect, improves the quality and efficiency of housing, greatly improves construction efficiency, shortens the construction period, and fully reflects the characteristics of "four savings and one environmental protection" of green buildings. It can be seen that prefabricated housing is the development direction of China's green buildings. The development of prefabricated housing can improve common quality problems such as structural accuracy, leakage, cracking, etc., improve sound insulation, thermal insulation, fire prevention and other performance, and facilitate system maintenance and updating. Prefabricated housing has a huge energy-saving and emission-reduction effect, improves the quality and efficiency of housing, greatly improves construction efficiency, shortens the construction period, and fully reflects the characteristics of "four savings and one environmental protection" of green buildings. It can be seen that prefabricated buildings are one of the symbols of the modernization of the construction industry, and prefabricated housing is the development direction of China's green buildings.

[0004] There are still many development bottlenecks in my country's prefabricated housing, including the following aspects:

[0005] 1. First, the technical standards for system design, production, installation, construction acceptance and evaluation of prefabricated housing have not yet been fully established; the construction technology and implementation process of prefabricated housing are not mature enough;

[0006] 2. There is no unified understanding of the structural system of prefabricated housing. The structural system is chaotic, and many owners, designers, and construction are still entangled in the so-called three major systems of prefabricated concrete, prefabricated steel structure, and prefabricated wood structure in foreign countries. In fact, any of the above simple structural systems is difficult to achieve a perfect modern prefabricated housing system;

[0007] At present, reinforced concrete structural systems, especially cast-in-place systems, are still in a dominant position. However, due to the need for a series of manual operations such as on-site formwork, steel bar binding and connection, concrete vibration and maintenance, the cast-in-place system has many disadvantages: long construction period; difficult to effectively control project costs; difficult to reliably guarantee project quality; difficult to achieve prefabricated construction;

[0008] 3. At present, there is a lack of building materials and supporting components, accessories and parts suitable for prefabricated housing in the market;

[0009] 4. Lack of professional designers, construction teams, monitoring units, etc.

[0010] The development of prefabricated housing can improve common quality problems such as structural accuracy, leakage, and cracking, improve sound insulation, thermal insulation, and fire prevention, and facilitate system maintenance and updating. Prefabricated housing has a huge effect on energy conservation and emission reduction, improves residential quality and efficiency, greatly improves construction efficiency, shortens the construction period, and fully reflects the characteristics of "four savings and one environmental protection" of green buildings. It can be seen that prefabricated housing is the development direction of China's green buildings. The development of prefabricated housing can improve common quality problems such as structural accuracy, leakage, and cracking, improve sound insulation, thermal insulation, and fire prevention, and facilitate system maintenance and updating. Prefabricated housing has a huge effect on energy conservation and emission reduction, improves residential quality and efficiency, greatly improves construction efficiency, shortens the construction period, and fully reflects the characteristics of "four savings and one environmental protection" of green buildings. It can be seen that prefabricated buildings are one of the symbols of modernization of the construction industry, and prefabricated housing is the development direction of China's green buildings.

[0011] There are still many development bottlenecks in my country's prefabricated housing, including the following aspects:

[0012] 1. First, the technical standards for system design, production, installation, construction acceptance and evaluation of prefabricated housing have not yet been fully established; the construction technology and implementation process of prefabricated housing are not mature enough;

[0013] 2. There is no unified understanding of the structural system of prefabricated housing. The structural system is chaotic, and many owners, designers, and construction are still entangled in the so-called three major systems of prefabricated concrete, prefabricated steel structure, and prefabricated wood structure in foreign countries. In fact, any of the above simple structural systems is difficult to achieve a perfect modern prefabricated housing system.

[0014] At present, reinforced concrete structural systems, especially cast-in-place systems, are still in a dominant position. However, due to the need for a series of manual operations such as on-site formwork, steel bar binding and connection, concrete vibration and maintenance, the cast-in-place system has many disadvantages: long construction period; difficult to effectively control project costs; difficult to reliably guarantee project quality; and difficult to achieve prefabricated construction.

[0015] 3. At present, there is a lack of building materials and supporting components, accessories and parts suitable for prefabricated housing in the market;

[0016] 4. Lack of professional designers, construction teams, monitoring units, etc.

[0017] Therefore, it is necessary to design a prefabricated building that is easy to install and has high structural strength. Summary of the invention

[0018] The first object of the present invention is to provide an assembled building with a firm structure and convenient installation. The above-mentioned object of the present invention is achieved through the following technical solutions: an assembled building, comprising a main frame structure formed by steel columns and steel beams, a wall body formed by integral prefabricated wall panels, and a floor slab formed by integral prefabricated floor panels, the integral prefabricated wall panels include prefabricated exterior wall panels and prefabricated interior wall panels, the steel columns and steel beams are hot-rolled seamless special-shaped steel pipes, and are connected to each other by node plates and bolts; the steel columns are arranged between adjacent prefabricated wall panels, and wet joints are arranged between the steel columns and the end faces of the prefabricated wall panels; the outer peripheral surfaces of the steel columns are buried in the wet joints and / or part of the outer peripheral surfaces are flush with the surface of the prefabricated wall panels; the prefabricated floor panels are integral prefabricated hollow panels.

[0019] By adopting the above technical scheme, the prefabricated building structure is mainly a hybrid structure, the components are mainly factory-prefabricated, the load-bearing structure is mainly steel structure, and the on-site installation is mainly bolted and riveted; the beam and column structural materials adopt hot-rolled special-shaped steel pipe frame structure; the steel columns will not be exposed on the wall, thus realizing the overall assembly, simple process flow, solid structure and good earthquake resistance of the building structure.

[0020] The present invention is further configured as follows: the steel column comprises an L-shaped steel pipe column, a T-shaped steel pipe column and a cross-shaped steel pipe column; the cross-section of the hollow cavity of the L-shaped steel pipe column is L-shaped, and is arranged at the corner of the outer wall; a third wet joint is arranged between the two vertical end faces of the L-shaped steel pipe column and the end face of the prefabricated outer wall panel; the inner side face of the L-shaped steel pipe column is flush with the inner surface of the prefabricated outer wall panel; the cross-section of the hollow cavity of the T-shaped steel pipe column is T-shaped, and the T-shaped steel pipe column comprises a straight portion and a vertical portion, and the two end faces of the straight portion are opposite to the opposite end faces. A first wet joint is arranged between the end faces of the corresponding prefabricated exterior wall panels; a second wet joint is arranged between the end face of the vertical portion and the end face of the prefabricated interior wall panel; the side face of the I-portion close to the vertical portion is flush with the inner surface of the prefabricated exterior wall panel; the cross-shaped steel pipe column has a cross-shaped cross-shaped hollow cavity; the cross-shaped steel pipe column is arranged between four prefabricated interior wall panels, and fourth wet joints are arranged between the four vertical end faces of the cross-shaped steel pipe column and the end faces of the prefabricated interior wall panels; the outer side face of the cross-shaped steel pipe column is flush with the surface of the prefabricated interior wall panel.

[0021] By adopting the above technical solution, by using L-shaped, T-shaped and cross-shaped steel pipe columns and wet joints, the exposure of steel columns that affects the use of space in the house is avoided, and the connection effect of the nodes is increased, making the building structure more solid.

[0022] The present invention is further configured as follows: a plurality of bolts extending into the wet joints are arranged on the outer surface of the special-shaped steel pipe column.

[0023] By adopting the above technical solution, the connection between the steel pipe column and the wet joint is further strengthened, making the building more integrated.

[0024] The present invention is further configured as follows: the prefabricated exterior wall panel comprises a load-bearing wall panel located outside the steel column and a prefabricated insulation layer embedded in a frame structure formed by the steel column and the steel beam; the inner surface of the prefabricated insulation layer is flush with the frame structure.

[0025] By adopting the above technical solution, a shear wall structure is formed by hanging on the exterior wall and embedding on the interior wall, which further increases the seismic resistance of the building.

[0026] The present invention is further configured that: the load-bearing wallboard portion of the prefabricated exterior wallboard is provided with a vertically penetrating through hole, and a prestressed beam is penetrated in the through hole to connect all the prefabricated exterior wallboards into a whole in the vertical direction.

[0027] By adopting the above technical solution, the prefabricated exterior wall panels are formed into an integral structure, thereby increasing the stress-bearing performance and earthquake resistance.

[0028] The present invention is further configured as follows: the load-bearing wallboard portion of the prefabricated exterior wallboard extends out of the vertical end surface to form a slurry retaining plate, and the slurry retaining plates of two adjacent prefabricated exterior wallboards are spliced.

[0029] By adopting the above technical solution, the need to install formwork on the outside of the exterior wall, set up scaffolding and other operations is avoided, thereby improving construction efficiency and safety.

[0030] The present invention is further configured as follows: it also includes prefabricated interior wall panels; the steel beam is an H-shaped steel tube beam with an H-shaped internal cavity, the upper surface and the lower surface of the H-shaped steel tube beam are concave to form a plug-in groove, and the upper and lower surfaces of the prefabricated interior wall panels are both provided with plug-in parts with matching shapes, and the plug-in parts on the upper surface of the prefabricated interior wall panels are inserted into the plug-in groove on the lower surface of the H-shaped steel tube beam.

[0031] By adopting the above technical solution, the steel tube beam and the prefabricated interior wall panel are plugged together, which facilitates the installation of the prefabricated interior wall panel. The two form a bite, which is more solid and avoids the formation of horizontal seams on the top surface of the prefabricated interior wall panel, thereby increasing the thermal insulation, heat insulation and noise reduction performance of the structure.

[0032] The present invention is further configured as follows: the prefabricated floor slab is overlapped on the upper surface of the H-shaped steel tube beam, the lower surface of the upper prefabricated interior wall panel is higher than the top surface of the prefabricated floor slab, and a fifth wet joint is arranged between the prefabricated floor slab, the upper prefabricated interior wall panel and the H-shaped steel tube beam.

[0033] By adopting the above technical solution, the fifth wet joint connects all the floor panels and wall panels together, thereby improving the integrity and earthquake resistance of the building structure.

[0034] The second object of the present invention is to provide a construction method for an assembled building. The above-mentioned invention object of the present invention is achieved through the following technical solution: A construction method for an assembled building, comprising the following steps:

[0035] Step 1: Use special hot-rolled special-shaped seamless steel pipe columns and steel pipe beams to assemble layer by layer to form the steel structure frame system of the first floor of the prefabricated house; the steel pipe columns and steel pipe beams are connected by node plates and bolts;

[0036] Step 2: Use the cavities of special hot-rolled special-shaped seamless steel pipe columns and steel pipe beams to install the common pipe wells for water supply, drainage, sewage and ventilation on the first floor, and install prefabricated components and accessories such as integral prefabricated stairs, elevator shafts, integral prefabricated kitchens, and integral prefabricated toilets;

[0037] Step 3: Install the first layer of bidirectional double-layer prestressed concrete integral hollow precast floor slab to form the floor;

[0038] Step 4: Install the first layer of "sandwich" prefabricated exterior wall panels with internal and external decoration and insulation, as well as the integral prefabricated balcony;

[0039] Step 5: Install the hollow high-strength lightweight concrete prefabricated interior wall panels with concave and convex mortise and tenon structures on all four sides.

[0040] Step 6: Pour wet joint concrete at all connection nodes to form an integral structure;

[0041] Step 7: Install integral prefabricated doors, windows, and other components;

[0042] Step 8: Repeat the above steps 1 to 7 layer by layer until the structural installation is completed;

[0043] Step 9: Complete the installation of water, electricity, heating and ventilation, and personalized interior and exterior decoration, final acceptance, and delivery for use.

[0044] In summary, the beneficial technical effects of the present invention are:

[0045] 1. The prefabricated building structure is mainly a hybrid structure, with factory-prefabricated components, steel structures as the main load-bearing structure, and bolting and riveting as the main method for on-site installation; the beam and column structural materials adopt hot-rolled special-shaped steel pipe frame (shear) structure; the inner and outer wall panels adopt the method of "external wall hanging, inner wall embedded", the outer wall is a "sandwich" structure with internal and external decoration and insulation, the inner wall is hollow high-strength lightweight concrete, all beams and columns are connected by high-strength bolts, and the floor is an integral two-way double-layer prestressed concrete hollow slab structure, thus realizing a building structure with good overall assembly, simple process flow, strong structure and good earthquake resistance;

[0046] 2. The hot-rolled special-shaped steel pipe frame can not only meet the structural force requirements, but also ensure that the steel columns do not protrude from the wall surface, making the house space more convenient to use;

[0047] 3. The grooved setting on the upper and lower surfaces of the steel beam increases the bite connection between it and the prefabricated wall panels and the fifth wet joint, avoiding the formation of horizontal through seams, increasing the connection effect of the building nodes, and greatly improving the overall seismic performance and sound insulation performance;

[0048] 4. The integrated prefabricated staircases, balconies, elevator shafts, integrated prefabricated kitchen and bathroom units; as well as the setting of shared pipe shafts for water supply, drainage, sewage and ventilation increase the assembly integration;

[0049] 5. The setting of the slurry retaining plate of the prefabricated exterior wall panel and the mortise and tenon structure of the prefabricated interior wall panel not only facilitates the installation operation, but also strengthens the connection of the nodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a schematic diagram of the overall structure of the prefabricated building;

[0051] Figure 2 It is a structural diagram of an L-shaped steel pipe column of a prefabricated structure;

[0052] Figure 3 Structural diagram of T-shaped steel pipe column of prefabricated structure;

[0053] Figure 4 It is a structural diagram of a cross-shaped steel pipe column of a prefabricated structure;

[0054] Figure 5 It is a schematic diagram of the structure in which the T-shaped column is connected to the inner and outer wall panels through a wet joint;

[0055] Figure 6 It is a schematic diagram of the layered structure and embedded connecting steel bars of prefabricated exterior wall panels;

[0056] Figure 7 It is a schematic diagram of the connection structure between the beam and the prefabricated exterior wall panels and floor slabs;

[0057] Figure 8 It is a schematic diagram of the connection structure between the L-shaped steel tube beam and the prefabricated exterior wall panel;

[0058] Fig. 9 It is a schematic diagram of the connection structure between the cross-shaped column and the prefabricated interior wall panel;

[0059] Fig.10 It is a schematic diagram of the connection structure between the beam and the prefabricated interior wall panels and floor slabs;

[0060] Fig.11 It is an exploded schematic diagram of the connection structure between prefabricated interior wall panels;

[0061] Fig.12 It is a structural diagram of a hollow precast floor slab;

[0062] Figure 13-Figure 15It is a schematic diagram of the node connection between the special-shaped column and the steel beam;

[0063] Fig.16 It is a process flow chart of prefabricated building construction based on the BIM platform;

[0064] Fig.17 Schematic diagram of the extrusion production line for special-shaped steel pipes;

[0065] Fig.18 It is a structural schematic diagram of the preliminary extrusion forming machine of the cross-shaped steel pipe column;

[0066] Fig.19 It is a schematic diagram of the structure of a mid-term extrusion forming machine for a cross-shaped steel pipe column;

[0067] Fig. 20 It is a schematic diagram of the structure of the final extrusion forming machine for the cross-shaped steel pipe column;

[0068] Fig.21 It is a structural schematic diagram of an L-shaped steel pipe column extrusion forming machine;

[0069] Fig. 22 It is a structural schematic diagram of a T-shaped steel pipe column extrusion forming machine;

[0070] Fig.23 It is a structural schematic diagram of an H-shaped steel tube beam extrusion forming machine.

[0071] In the figure, 1, steel column; 11, L-shaped steel pipe column; 12, T-shaped steel pipe column; 121, straight part; 122, vertical part; 13, cross-shaped steel pipe column; 14, stud; 2, steel beam; 21, plug-in groove; 22, long stud; 31, prefabricated exterior wall panel; 311, load-bearing wall panel; 312, prefabricated insulation layer; 313, slurry retaining plate; 314, through hole; 315, interior decoration layer; 316, transverse joint; 317, reinforced steel wire mesh; 32, prefabricated interior wall panel; 321, trapezoidal protrusion; 322, plug-in part; 323, second plug-in part; 32 4. Trapezoidal groove; 4. Precast floor slab; 41. Prestressed high-strength notched steel wire; 5. Wet joint; 51. First wet joint; 52. Second wet joint; 53. Third wet joint; 54. Fourth wet joint; 55. Fifth wet joint; 6. Connecting steel bars; 61. First U-shaped bar; 62. Second U-shaped bar; 63. Third U-shaped bar; 64. Vertical connecting bar; 65. Horizontal connecting bar; 66. Connecting bar; 7. Node plate; 71. Bolt; 8. Extrusion molding machine; 81. Surface roller; 82. Angle roller; 83. Roller shaft; 84. Molding roller; 9. Seamless round tube. DETAILED DESCRIPTION

[0072] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0073] Embodiment 1:

[0074] like Figure 1 As shown, an assembled building disclosed in the present invention comprises a main frame structure formed by steel columns 1 and steel beams 2, a wall body formed by integral prefabricated wall panels, and a floor slab formed by integral prefabricated floor panels 4, wherein the integral prefabricated wall panels comprise prefabricated exterior wall panels 31 and prefabricated interior wall panels 32, the steel columns 1 and steel beams 2 are hot-rolled seamless special-shaped steel pipes (the processing technology is specifically introduced in the fourth embodiment), and are connected to each other by node plates 7 and bolts 71; the steel column 1 is arranged between adjacent prefabricated wall panels, and a wet joint 5 is arranged between the steel column 1 and the end face of the prefabricated wall panel; all the peripheral surfaces of the steel column 1 are buried in the wet joint 5, or part of the peripheral surface is flush with the surface of the prefabricated wall panel (that is, the steel column 1 does not protrude and is exposed on the wall surface); the prefabricated floor panel 4 is an integral prefabricated hollow panel.

[0075] like Figure 2-Figure 4 As shown, the steel column 1 includes an L-shaped steel pipe column 11, a T-shaped steel pipe column 12 and a cross-shaped steel pipe column 13. In addition to the commonly used L-shaped, T-shaped and cross-shaped steel pipes shown in the figure, it can also be a hot-rolled seamless special-shaped steel pipe with a square, rectangular or other cross-sectional shape.

[0076] like Figure 3 and Figure 5 As shown, the cross-section of the hollow cavity of the T-shaped steel pipe column 12 is T-shaped. The T-shaped steel pipe column 12 includes a straight portion 121 and a vertical portion 122. A first wet joint 51 is arranged between the two end surfaces of the straight portion 121 and the corresponding end surfaces of the prefabricated exterior wall panel 31; a second wet joint 52 is arranged between the end surface of the vertical portion 122 and the end surface of the prefabricated interior wall panel 32; and the side surface of the straight portion 121 close to the vertical portion 122 is flush with the inner surface of the prefabricated exterior wall panel 31.

[0077] The prefabricated exterior wall panel 31 includes a load-bearing wall panel 311 located outside the steel column 1 and a prefabricated insulation layer 312 embedded in the frame structure formed by the steel column 1 and the steel beam 2. The load-bearing wall panel 311 can be made of high-grade concrete, such as C40 concrete; the prefabricated insulation layer 312 can be made of other solidifying materials such as lightweight concrete or ceramsite concrete.

[0078] Furthermore, the load-bearing wallboard 311 can be made of colored high-strength concrete, so as to have a decorative effect on the outer surface. Alternatively, an integrally cast decorative layer can be provided on the inner and outer surfaces of the load-bearing wallboard, so that the prefabricated outer wallboard 31 is prefabricated into a "sandwich" structure. As shown in the figure, when the inner decorative layer 315 is provided, the inner surface of the inner decorative layer 315 is flush with the frame structure. Preferably, the thicknesses of the load-bearing wallboard 311, the prefabricated insulation layer 312 and the inner decorative layer 315 are 90 mm, 130 mm and 20 mm respectively.

[0079] When the inner decoration layer 315 is not provided, the inner surface of the prefabricated insulation layer 312 is flush with the frame structure. The prefabricated insulation layer 312 or the inner decoration layer 315 is flush with the frame structure, that is, the inner surface of the prefabricated exterior wall panel 31 is flush with the peripheral side surface of the steel column 1 that is not in contact with the wet joint 5, thereby solving the problem in the prior art that the steel column 1 is exposed to the wall surface, affecting the use of the space inside the house.

[0080] In order to strengthen the connection between the steel column 1 and the wet joint 5 , a plurality of bolts 14 extending into the wet joint 5 are arranged on the outer surface of the T-shaped steel pipe column 12 .

[0081] During construction, after the steel column 1 and the prefabricated exterior wall panel 31 are installed, vertical side molds are installed on the outer and inner surfaces of the prefabricated exterior wall panel 31, and then the concrete in the first wet joint 51 is poured; synchronously, vertical side molds are installed on the surface of the prefabricated interior wall panel, and then the concrete in the second wet joint 52 is poured.

[0082] In order to prevent the outer surface of the T-shaped steel pipe column 12 from being exposed, the thickness of the straight portion 121 of the T-shaped steel pipe column 12 is smaller than the thickness of the prefabricated exterior wall panel 31 , so that the outer side surface of the straight portion 121 is buried in the concrete of the first wet joint 51 .

[0083] Furthermore, since the vertical side formwork on the outer surface of the prefabricated exterior wall panel 31 needs to be installed on an operating platform such as a scaffolding outside the building, the installation cost is high and it is unsafe. Figure 5 and Figure 6 As shown, the load-bearing wall panel 311 of the prefabricated exterior wall panel 31 partially extends out of the vertical end surface to form a slurry retaining plate 313, and the slurry retaining plates 313 of two adjacent prefabricated exterior wall panels 31 are spliced, thereby replacing the outer template of the first wet joint 51. In order to ensure the thickness of the concrete between the outer side surface of the I-section 121 of the T-shaped steel pipe column 12 and the slurry retaining plate 313, the thickness of the slurry retaining plate 313 is less than the thickness of the load-bearing wall panel 311, which can be 20-30mm. Furthermore, a reinforcing steel wire mesh 317 is provided in the slurry retaining plate 313, and the reinforcing steel wire mesh 317 extends into the load-bearing wall panel 311, or is provided throughout the load-bearing wall panel 311 and the slurry retaining plate 313, so as to increase the strength of the slurry retaining plate 313.

[0084] In order to strengthen the connection between two adjacent prefabricated exterior wall panels 31 and between the prefabricated exterior wall panels 31 and the first wet joint 51, the load-bearing wall panel 311 is pre-embedded with connecting steel bars 6 extending out of the end face; the connecting steel bars 6 of two adjacent prefabricated exterior wall panels 31 are connected to each other. Preferably, as shown in the figure, the connecting steel bars 6 are U-shaped steel bars, and the two ends of the U-shaped steel bars are pre-embedded in the prefabricated exterior wall panels 31, and the elbows extend into the first wet joint 51. The U-shaped steel bars can be divided into a first U-shaped bar 61 and a second U-shaped bar 62. Figure 5As shown, the first U-shaped rib 61 extends between the outer side of the straight section 121 of the T-shaped steel pipe column 12 and the slurry retaining plate 313. The first U-shaped ribs 61 on the two prefabricated exterior wall panels 31 are staggered in the vertical direction and form a cross so that the two overlap in vertical projection. The vertical connecting rib 64 is inserted into the elbow, thereby more effectively connecting the two prefabricated exterior wall panels 31. The portion of the second U-shaped rib 62 extending from the end face of the prefabricated exterior wall panel 31 is located between the end face of the straight section 121 of the T-shaped steel pipe column 12 and the end face of the prefabricated exterior wall panel 31.

[0085] In order to enhance the integrity of the exterior wall, Figure 5 and Figure 6 As shown, the load-bearing wallboard 311 of each prefabricated exterior wall panel 31 is provided with two vertical through holes 314, and a prestressed bundle is inserted in the through hole 314 to connect all the prefabricated exterior wall panels 31 into a whole in the vertical direction, and concrete or grouting material is poured between the prestressed bundle and the inner wall of the through hole 314. The positions of the prefabricated exterior wall panels 31 at the top and bottom are locally reinforced by adding steel bars or increasing the concrete grade. Of course, holes for installing anchors can also be opened on the side of the strip foundation to connect the exterior wall and the foundation into a whole.

[0086] like Figure 7 As shown, the height of the prefabricated exterior wall panel 31 is consistent with the floor height, and the transverse joint 316 is set at the center of the prefabricated floor slab 4 of the floor, and can also be set at the center of the beam height.

[0087] like Figure 2 and Figure 8 As shown, the cross section of the hollow cavity of the L-shaped steel pipe column 11 is L-shaped, and it is set at the corner of the outer wall. A third wet joint 53 is set between the two vertical end faces of the L-shaped steel pipe column 11 and the end face of the prefabricated outer wall panel 31; the inner side surface of the L-shaped steel pipe column 11 is flush with the inner surface of the prefabricated outer wall panel 31. Furthermore, a plurality of studs 14 extending into the wet joint 5 are set on the outer surface of the L-shaped steel pipe column 11.

[0088] like Figure 3 and Fig. 9 As shown, the cross-section of the hollow cavity of the cross-shaped steel pipe column 13 is cross-shaped; the cross-shaped steel pipe column 13 is arranged between four prefabricated interior wall panels 32, and a fourth wet joint 54 is arranged between the four vertical end faces of the cross-shaped steel pipe column 13 and the end faces of the prefabricated interior wall panels 32; the thickness of the prefabricated interior wall panels 32 can be the same as that of the cross-shaped steel pipe column 13, so as to ensure that the outer side of the cross-shaped steel pipe column 13 is flush with the surface of the prefabricated interior wall panels 32. Of course, the thickness of the prefabricated interior wall panels 32 can also be greater than the thickness of the cross-shaped steel pipe column 13. After installation, the concave part between the cross-shaped steel pipe column 13 and the wall surface can be closed with a decorative strip.

[0089] Furthermore, water supply, drainage, sewage and ventilation pipes are installed in the hollow cavity of the cross-shaped steel pipe column 13, or a common pipe well is installed in the hollow receptor.

[0090] Combination Fig.10 The steel beam 2 is an H-shaped steel tube beam with an H-shaped internal cavity. The upper and lower surfaces of the H-shaped steel tube beam are concave to form a plug-in groove 21. The cross-section of the plug-in groove 21 can be rectangular or trapezoidal. The upper surface of the prefabricated interior wall panel 32 is provided with a plug-in portion 322 of matching shape. The plug-in portion 322 on the upper surface of the prefabricated interior wall panel 32 is inserted into the plug-in groove 21 on the lower surface of the H-shaped steel tube beam. The thickness of the prefabricated interior wall panel 32 in the figure is less than the thickness of the steel beam 2.

[0091] The prefabricated interior wall panels 32 may be hollow high-strength lightweight concrete panels. Fig. 9 and Fig.11 As shown, the side end surface of the prefabricated interior wall panel is provided with male and female dovetail grooves, and two adjacent prefabricated interior wall panels are installed by using the male and female dovetail grooves. The male and female dovetail grooves can be ordinary trapezoidal protrusions 321 and trapezoidal grooves 324. Fig. 9 As shown, the trapezoidal protrusion 321 and the trapezoidal groove 324 of the prefabricated interior wall panel 32 can better engage with the fourth wet joint 54, thereby connecting the cross-shaped steel pipe column 13 and the prefabricated interior wall panel 32 into a whole.

[0092] like Fig.12 As shown, the prefabricated floor slab 4 is an integral prefabricated hollow slab. An integrally formed decorative layer, such as ceramic tiles, is provided on the upper surface of the prefabricated floor slab 4; an integrally formed ceiling pattern layer is directly counter-formed on the bottom surface. Double-layer bidirectional prestressed steel bars or prestressed high-strength notched steel wires 41 are provided in the prefabricated floor slab 4, thereby increasing the applicable range of the span of the prefabricated floor slab 4. Preferably, the prestressing force can be constructed using the short-line method. Under the premise of adopting the above-mentioned scheme, it is possible to use a whole floor slab for one room without the need for secondary decoration, thereby reducing the construction process and overcoming the problem of the seams of the traditional prefabricated panels. Furthermore, the connection end face of the prefabricated floor slab 4 is pre-embedded with a connecting rib 66 extending out of the connection end face.

[0093] Replay Fig.10 The precast floor slab 4 is overlapped on the upper surface of the H-shaped steel tube beam, the lower surface of the upper precast interior wall panel 32 is higher than the top surface of the precast floor slab 4, and a fifth wet joint 55 is set between the precast floor slab 4, the upper precast interior wall panel 32 and the H-shaped steel tube beam. The connecting ribs 66 of two adjacent precast floor slabs 4 are connected to each other. The connecting ribs 66 can be third U-shaped ribs 63. Both ends of the third U-shaped ribs 63 are pre-buried in the precast floor slab 4, and the elbow part extends into the fifth wet joint 55. The third U-shaped ribs 63 of the two precast floor slabs 4 intersect each other, and a transverse connecting rib 65 is inserted in the elbow. The connecting ribs 66 can also be steel bars with elbows, and a steel cage is set inside the fifth wet joint 55 to strengthen the node at this location.

[0094] Combination Fig.10 and Fig.11 The lower surface of the prefabricated inner wall panel 32 is provided with a protruding second plug-in portion 323, which is inserted into the fifth wet joint 55, thereby preventing the bottom surface of the prefabricated inner wall panel 32 from forming a horizontal through seam. During construction, after the floor slab is installed, the upper prefabricated inner wall panel 32 is installed in place, the bottom is temporarily supported, and then the corner side form is installed, and finally concrete is poured from the holes reserved on the side form, preferably self-compacting concrete.

[0095] In addition, the top surface of the fifth wet joint 55 can also be flush with the top surface of the prefabricated floor 4, and the bottom surface of the prefabricated interior wall panel 32 is flat and can be directly installed on the top surface of the fifth wet joint 55 (this solution corresponds to the construction method in Example 3, not shown in the figure).

[0096] Replay Figure 7 The connection between the prefabricated exterior wall panel 31 and the steel beam 2 and the prefabricated floor 4 is also provided with a fifth wet joint 55, and a pre-buried connecting rib 66 is provided near the fifth wet joint 55 on the load-bearing wall panel 311 of the prefabricated exterior wall panel 31, and the connecting rib 66 of the prefabricated exterior wall panel 31 is connected to the connecting steel bar 6 on the prefabricated floor 4. Furthermore, the connecting rib 66 of the prefabricated exterior wall panel 31 and the connecting steel bar 6 on the prefabricated floor 4 can both be U-shaped ribs in the horizontal direction, and a long stud 22 is provided on the top surface of the H-shaped steel tube beam, and the long stud 22 vertically passes through the U-shaped rib to connect the prefabricated exterior wall panel 31 with the prefabricated floor 4.

[0097] like Figures 13 to 15 As shown, all steel beams 2 and steel columns 1 are connected by node plates 7 and bolts 71, so as to realize the rapid installation of the steel structure. The steel beams 2 are arranged on the side of the steel columns 1, and the upper and lower steel columns 1 are directly connected by node plates 7.

[0098] Furthermore, prefabricated buildings also include factory-prefabricated integral staircases, balconies, elevator shafts, prefabricated integral kitchen and bathroom units, and integrally assembled doors and windows.

[0099] Embodiment 2:

[0100] A construction method for buildings, combined with Fig.16 , including the following steps:

[0101] Step 1: Use the BIM platform to perform three-dimensional design of the building structure for all components, input relevant parameters for construction simulation, conduct construction site organization and process simulation, construction and installation training, construction simulation collision, construction simulation of complex nodes, and guide the processing of components;

[0102] Step 2: Use special hot-rolled special-shaped seamless steel pipe columns and steel pipe beams to assemble layer by layer to form a steel structure frame system for the first floor of the prefabricated house; the steel pipe columns and steel pipe beams are connected by node plates 7 and bolts 71;

[0103] Step 3: Use the cavities of special hot-rolled special-shaped seamless steel pipe columns and steel pipe beams to install the common pipe wells for water supply, drainage, sewage and ventilation on the first floor, and install prefabricated components and accessories such as integral prefabricated stairs, elevator shafts, integral prefabricated kitchens, and integral prefabricated toilets;

[0104] Step 4: Install the first layer of bidirectional double-layer prestressed concrete integral hollow prefabricated floor slab 4 to form a floor slab;

[0105] Step 5: Install the first layer of "sandwich" prefabricated exterior wall panels 31 with internal and external decoration and insulation layer, and the integral prefabricated balcony;

[0106] Step 6: Install the hollow high-strength lightweight concrete prefabricated interior wall panels 32 with concave-convex mortise and tenon structures on the four sides of the first layer; install the steel pipe columns, prefabricated exterior wall panels 31 and prefabricated interior wall panels 32 of the second layer, and make temporary supports at the bottom of the prefabricated exterior wall panels 31 and prefabricated interior wall panels 32 to leave a pouring space for the fifth wet joint 55;

[0107] Step 7: pouring wet joints 5 concrete of all connection nodes of the first layer to form an integral structure; installing the steel tube beams of the second layer;

[0108] Step 8: Install the integral prefabricated doors, windows and other components of the first floor;

[0109] Step 9: Repeat the above steps 3 to 8 layer by layer until the structural installation is completed;

[0110] Step 10: Complete the installation of water, electricity, heating and ventilation, and personalized interior and exterior decoration, final acceptance, and delivery for use.

[0111] During the construction and delivery process from the second to the tenth step, the BIM platform is used to guide the factory prefabrication and on-site installation of components and parts, and to achieve the transmission and sharing of logistics and procurement information, as well as all-round monitoring of construction progress, quality and safety.

[0112] Embodiment three:

[0113] The difference from the second embodiment is that when the top surface of the fifth wet joint 55 is flush with the top surface of the prefabricated floor slab 4, and the bottom surface of the prefabricated interior wall panel 32 is a plane and is directly installed on the top surface of the fifth wet joint 55, the sixth to eighth steps become:

[0114] Step 6: Install the first layer of hollow high-strength lightweight concrete prefabricated interior wall panels 32 with concave-convex tenon and mortise structures on three sides;

[0115] Step 7: Pour the wet joints 5 concrete of all the connection nodes of the first layer to form an integral structure;

[0116] Step 8: Install the integral prefabricated doors, windows and other components of the first floor;

[0117] Step 9: Repeat the construction procedures from step 2 to step 8 above layer by layer until the structural installation is completed.

[0118] The prefabricated building structure is mainly a mixed structure of steel frame and shear wall, the components are mainly prefabricated in factories, the load-bearing structure is mainly steel structure, and the on-site installation is mainly bolted and riveted; the beam and column structural materials adopt hot-rolled special-shaped steel pipe frame (shear) structure; the prefabricated exterior wall panels 31 adopt the "exterior wall hanging, interior wall embedded" method, the exterior wall is a "sandwich" structure with internal and external decoration and insulation, the interior wall is hollow high-strength lightweight concrete, all beams and columns are connected by high-strength bolts 71, and the floor is an integral two-way double-layer prestressed concrete hollow slab structure, thus realizing a building structure with good overall assembly, simple process flow, strong structure and good earthquake resistance;

[0119] Embodiment four:

[0120] Steel beams and columns in traditional steel structure buildings are mainly formed by cold bending or cutting and welding of steel plates, and are basically square and rectangular cross-sections, or are directly processed by solid steel. Cold-bent steel is limited by processing technology, not only has thin walls, but also has poor quality of high-frequency welding welds and large rounded corners, making it difficult to be used as important beam and column structures; while welding forming not only requires a large amount of welding, is labor-intensive and time-consuming, but also has poor appearance, large deformation, and it is difficult to eliminate welding residual stress.

[0121] In addition, due to various restrictions, traditional steel structure rods are mostly square and rectangular cross-sections, and the cross-sectional dimensions are larger than the thickness of the inner and outer walls. The protruding parts of the steel structure rods are difficult to handle, and secondary decoration is difficult. They are also prone to cracks and leakage, creating quality risks.

[0122] The steel columns 1 and steel beams 2 described in Examples 1 to 3 are all hot-rolled seamless special-shaped steel pipes, which are special-shaped steel pipes formed by a new production process.

[0123] like Fig.17 As shown, the hot-rolled seamless special-shaped steel pipe processing technology is to transform the traditional hot-rolled seamless steel pipe equipment and process, and use a dedicated multiple extrusion molding machine 8 to extrude a series of hot-rolled seamless special-shaped steel pipes suitable for beam and column structure standards of prefabricated building structures. Standard section specifications include but are not limited to rectangular, L-shaped, T-shaped, cross-shaped and cavity H-shaped.

[0124] At a high temperature above 900°C, the seamless round tube 9 is passed through an extrusion processing line composed of multiple groups of extrusion molding machines 8. The multiple groups of extrusion molding machines 8 are installed in the middle of the online equipment on the hot-rolled seamless steel pipe production line, specifically, they can be installed behind the sizing rack or the reducing rack on the hot-rolled seamless steel pipe production line, and work online synchronously with other equipment; the multiple groups of extrusion molding machines 8 gradually shape the seamless round tube 9 through multiple rolling.

[0125] Preferably, the rolling process of the seamless round tube 9 is carried out simultaneously with the processes of heating, sizing, reducing, secondary heating, straightening, cutting and the like of the hot-rolled seamless steel tube to maintain the same quality as the hot-rolled seamless steel tube.

[0126] See also Figure 18-20 , taking the processing of the cross-shaped steel pipe column 13 as an example for introduction, each group of extrusion molding machines 8 includes a frame and four surface rollers 81 and four angle rollers 82 rotatably installed on the frame, and the four surface rollers 81 and angle rollers 82 are arranged at intervals from each other according to the shape of the cross-shaped steel pipe column 13; the shapes of the surface rollers 81 and angle rollers 82 on different extrusion molding machines 8 gradually approach the outer dimensions of the cross-shaped steel pipe column 13 according to the direction in which the seamless round tube 9 passes, and all the surface rollers 81 and angle rollers 82 on the same group of extrusion molding machines 8 are enclosed to form the outer contour line of the cross-shaped steel pipe column 13; when the seamless round tube 9 passes, the surface rollers 81 and the angle rollers 82 both rotate around the roller shaft 83, the surface rollers 81 extrude the arc surface of the seamless round tube 9 into a plane, and the angle rollers 82 extrude the arc surface of the round tube into an inwardly concave right-angled surface.

[0127] More specifically, the angle rollers 82 on the first several groups of extrusion forming machines 8 extrude the arc surface of the seamless round tube 9 into a plane, and the angle rollers 82 on the latter several groups of extrusion forming machines 8 extrude the plane into a concave right-angled surface; that is, the angle rollers 82 and the surface rollers 81 on the first several groups of extrusion forming machines 8 work together to extrude the seamless round tube 9 into a polygon, and the angle rollers 82 on the latter several groups of extrusion forming machines 8 extrude the corresponding planes of the seamless round tube 9 into a concave right-angled surface.

[0128] like Fig.21 As shown, the extrusion forming machine 8 of the L-shaped steel pipe column 11 includes an angle roller 82 and four surface rollers 81.

[0129] like Fig. 22 As shown, the extrusion forming machine 8 of the T-shaped steel pipe column 12 includes two angle rollers 82 and four surface rollers 81.

[0130] like Fig.23 As shown, the extrusion molding machine 8 for the H-shaped steel pipe (i.e., H-shaped steel pipe beam) includes two surface rollers 81 and two forming rollers 84. The outer peripheral surface of the forming roller 84 gradually evolves from a flat surface to an outwardly protruding "J"-shaped surface, thereby extruding the seamless round pipe 9 into an H-shaped steel beam 2 with two concave outer surfaces.

[0131] Compared with the performance of similar materials, hot-rolled seamless special-shaped steel pipes can be rolled into special-shaped sections of various specifications and materials through a special extrusion forming machine 8. The mechanized production efficiency is high and the quality is good. It can be widely used in the main load-bearing components such as beams and columns of prefabricated steel structure buildings.

[0132] In addition, the processing technology of hot-rolled seamless special-shaped steel pipes can also be applied to the processing of steel pipe components in the fields of automobiles, shipbuilding and equipment platforms; materials of different materials and specifications can also be heated and extruded to form special-shaped pipe fittings.

[0133] The embodiments of this specific implementation method are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An assembled building, comprising a main frame structure formed by steel columns and steel beams, a wall body formed by integral prefabricated wall panels, and a floor slab formed by integral prefabricated floor panels (4), wherein the integral prefabricated wall panels include prefabricated exterior wall panels (31) and prefabricated interior wall panels (32), characterized in that: The steel column (1) and the steel beam (2) are hot-rolled seamless special-shaped steel pipes, which are connected to each other by node plates (7) and bolts (71); the steel column (1) is arranged between adjacent prefabricated wall panels, and a wet joint (5) is arranged between the steel column (1) and the end surface of the prefabricated wall panel; each outer peripheral surface of the steel column (1) is buried in the wet joint (5) and / or part of the outer peripheral surface is flush with the surface of the prefabricated wall panel; the prefabricated floor slab (4) is an integral prefabricated hollow slab; The steel beam (2) is an H-shaped steel tube beam with an H-shaped internal cavity. The upper surface and the lower surface of the H-shaped steel tube beam are concave to form a plug-in groove (21). The upper surface of the prefabricated interior wall panel (32) located at the lower part of the steel beam (2) is provided with a plug-in portion (322) of matching shape. The plug-in portion (322) on the upper surface of the prefabricated interior wall panel (32) is inserted into the plug-in groove (21) on the lower surface of the H-shaped steel tube beam. The prefabricated floor slab (4) located at the upper part of the steel beam (2) is overlapped on the upper surface of the H-shaped steel tube beam. The lower surface of the upper prefabricated interior wall panel (32) is higher than the top surface of the prefabricated floor slab (4). A fifth wet joint (55) is provided between the prefabricated floor slab (4), the upper prefabricated interior wall panel (32) and the H-shaped steel tube beam. The connecting end surface of the hollow prefabricated floor slab (4) is pre-buried with a connecting rib (66) extending out of the connecting end surface; the connecting ribs (66) of two adjacent hollow prefabricated floor slabs (4) are mutually connected and located inside the fifth wet joint (55); a protruding second plug-in portion (323) is provided on the lower surface of the upper prefabricated interior wall panel (32), and the second plug-in portion (323) is inserted into the fifth wet joint (55); the connecting rib (66) is a third U-shaped rib (63), both ends of the third U-shaped rib (63) are pre-buried in the hollow prefabricated floor slab (4), and the elbow portion extends into the fifth wet joint (55); the third U-shaped ribs (63) of the two hollow prefabricated floor slabs (4) intersect each other, and a transverse connecting rib (65) is inserted into the elbow.

2. The prefabricated building according to claim 1, characterized in that: The steel column (1) comprises an L-shaped steel pipe column (11), a T-shaped steel pipe column (12) and a cross-shaped steel pipe column (13); The cross section of the hollow cavity of the L-shaped steel pipe column (11) is L-shaped and is arranged at the corner of the outer wall. A third wet joint (53) is arranged between the two vertical end faces of the L-shaped steel pipe column (11) and the end face of the prefabricated outer wall panel (31); the inner side face of the L-shaped steel pipe column (11) is flush with the inner surface of the prefabricated outer wall panel (31); The cross section of the hollow cavity of the T-shaped steel pipe column (12) is T-shaped. The T-shaped steel pipe column (12) comprises a straight portion (121) and a vertical portion (122). A first wet joint (51) is arranged between the two end surfaces of the straight portion (121) and the corresponding end surfaces of the prefabricated exterior wall panel (31); a second wet joint (52) is arranged between the end surface of the vertical portion (122) and the end surface of the prefabricated interior wall panel (32); and the side surface of the straight portion (121) close to the vertical portion (122) is flush with the inner surface of the prefabricated exterior wall panel (31); The cross-section of the hollow cavity of the cross-shaped steel pipe column (13) is cross-shaped; the cross-shaped steel pipe column (13) is arranged between four prefabricated interior wall panels (32), and fourth wet joints (54) are arranged between the four vertical end faces of the cross-shaped steel pipe column (13) and the end faces of the prefabricated interior wall panels (32); the outer side surface of the cross-shaped steel pipe column (13) is flush with the surface of the prefabricated interior wall panels (32).

3. The prefabricated building according to claim 2, characterized in that: A plurality of bolts (14) extending into the wet joints (5) are arranged on the outer surface of the special-shaped steel pipe column.

4. The prefabricated building according to claim 2, characterized in that: The prefabricated exterior wall panel (31) comprises a load-bearing wall panel (311) located outside the steel column (1) and a prefabricated thermal insulation layer (312) embedded in a frame structure formed by the steel column (1) and the steel beam (2); the inner surface of the prefabricated thermal insulation layer (312) is flush with the frame structure.

5. The prefabricated building according to claim 4, characterized in that: The load-bearing wallboard (311) of the prefabricated exterior wallboard (31) is provided with a vertically penetrating through hole (314), and a prestressed beam is passed through the through hole (314) to connect all the prefabricated exterior wallboards (31) into a whole in the vertical direction.

6. The prefabricated building according to claim 4, characterized in that: The load-bearing wall panels (311) of the prefabricated exterior wall panels (31) partially extend out of the vertical end surface to form a slurry retaining plate (313), and the slurry retaining plates (313) of two adjacent prefabricated exterior wall panels (31) are spliced.

7. The prefabricated building according to claim 6, characterized in that: The thickness of the slurry retaining plate (313) is smaller than that of the load-bearing wall panel (311), and the load-bearing wall panel (311) is pre-embedded with connecting steel bars (6) extending out of the end surface on the vertical end surface; the connecting steel bars (6) of two adjacent prefabricated exterior wall panels (31) are connected to each other.

8. A construction method for an assembled building, characterized in that: The construction steps include: The first step is to assemble the steel structure frame system of the first floor of the prefabricated house layer by layer using specially made hot-rolled special-shaped seamless steel pipe columns and steel pipe beams; the steel pipe columns and steel pipe beams are connected by node plates (7) and bolts (71); Step 2: Use the cavities of special hot-rolled special-shaped seamless steel pipe columns and steel pipe beams to install the common pipe wells for water supply, drainage, sewage and ventilation on the first floor, and install prefabricated components and accessories such as integral prefabricated stairs, elevator shafts, integral prefabricated kitchens, and integral prefabricated toilets; Step 3: installing the first layer of bidirectional double-layer prestressed concrete integral hollow precast floor slab (4), connecting the connecting ribs (66) of two adjacent hollow precast floor slabs (4) to each other, wherein the connecting ribs (66) are third U-shaped ribs (63), both ends of the third U-shaped ribs (63) are pre-buried in the hollow precast floor slab (4), and the elbow part is extended, and the third U-shaped ribs (63) of the two hollow precast floor slabs (4) are crossed to each other, and a transverse connecting rib (65) is inserted in the elbow to form a floor slab; Step 4: Install the first layer of "sandwich" prefabricated exterior wall panels (31) with internal and external decoration and insulation, and the integral prefabricated balcony; Step 5: Install the hollow high-strength lightweight concrete prefabricated interior wall panels (32) with concave-convex mortise and tenon structures on four sides; install the steel pipe columns, prefabricated exterior wall panels (31) and prefabricated interior wall panels (32) of the second layer, and make temporary supports at the bottom of the prefabricated exterior wall panels (31) and prefabricated interior wall panels (32) to leave space for pouring the fifth wet joint (55); Step 6: pouring concrete into the wet joints (5) of all the connection nodes to form an integral structure, wherein the elbow portion of the third U-shaped reinforcement (63) is located in the fifth wet joint (55); Step 7: Install integral prefabricated doors, windows, and other components; install the steel tube beams of the second floor; Step 8: Repeat the above steps 2 to 7 layer by layer until the structural installation is completed; Step 9: Complete the installation of water, electricity, heating and ventilation, and personalized interior and exterior decoration, final acceptance, and delivery for use.

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