Xirong's discussion on the application of foreign industrialized steel structure housing

Overview: Industrial housing refers to prefabricated buildings in which the components and parts of the house are processed in a factory and transported to the site for assembly. This kind of building design standard is finalized, the components are processed on the automated production line, and the site adopts bolts, self-tapping screws and other connecting parts and sealing materials dry assembly, no wet operation, convenient construction and installation. The skeleton of this industrial house can be made of wood structure and steel structure. Due to the fireproof, anti-corrosion, ant-proof treatment and price of wood structures, most of them use steel structures. Compared with other structures, steel structure can be said to be the most in line with the industrial production mode of the structural form, it is the easiest to achieve design standardization, structural parts production factory, construction mechanization, assembly.

Compared with the traditional brick-concrete structure, industrialized low-rise houses have the following advantages: the house has a light weight: this reduces the cost of the foundation, saves the workload of transportation and installation, and has good seismic performance; Factory production of skeleton steel components, enclosure structure plates and various accessories, with high precision and good quality; The construction and installation is simple, the cycle is short, and the 200m2 villa can be built in 2 months from the foundation to the I decoration; The building shape is beautiful, the room layout is flexible, and the pipeline and various wiring arrangements are simple; The on-site construction is civilized, the foundation above is all dry construction methods, no wet work, less construction waste, and it is an environmentally friendly building; Suitable for mountainous areas, remote areas and areas lacking local building materials; The real turnkey project, skeleton, roof, wall, interior wall and interior decoration, hot water system, central air conditioning and home appliances installation and commissioning are all completed, no secondary decoration is required, users can move in in time.

This kind of industrialized

low-rise housing has been widely used abroad, Japan every year to build about 200,000 new industrialized houses, according to each building of 150m2, construction area of 30 million m2.In Japan, there are dozens of industrialized housing professional manufacturers, including relatively large seven or eight, Sekisui, Yamato, Misawa Housing Co., Ltd. are very famous manufacturers, these companies have technical departments, design departments, production plants, The Construction Department, the Housing Research Institute, and sales offices throughout the country are fully responsible for the marketing, research and development, design, component processing, construction and installation and after-sales service of industrial housing. The company is not large and complete, often the panels and accessories, construction and installation of the envelope are provided and constructed by specialized affiliates and brand-name manufacturers.

In

addition to complying with the requirements of the Japanese Building Standards Act and various regulations and codes, the design and construction of industrialized houses must also pass the industrial performance certification system recognized by the Minister of Construction, the excellent energy-saving building certification system, and the excellent residential parts certification system. The newly developed 3-storey light steel villa must also pass various certifications of the Ministry of Construction, and various material and structural performance tests must be carried out before identification, including physical fire tests. This strict censorship system ensures that consumers receive high-quality homes.

In addition, perfect after-sales service and the warranty period of various components make consumers rest assured and satisfied. Therefore, villa sales in Japan have been on an upward trend.

In the mid-80s of the 20th century, with the deepening of China's reform and opening up, industrialized steel villas also entered China, and Shanghai Longbai Hotel, Dalian Taoyuan Villa, Beijing Guangming Apartment, etc. introduced more than 200 steel villas of Yamato, Sekisui and Misawa House Co., Ltd. in Japan. In recent years, Suzhou and Guangzhou have introduced two- and three-story villas from the United States and Australia, and the skeletons, envelopes, equipment and other sets of these houses have been imported from abroad, and the Chinese side is only responsible for the foundation, floor and assembly of house components. At present, some domestic units are also carrying out the pilot of steel structure villas.

First author: Gong Xiaoyun female born in June 1943 professor-level senior engineer 2 Japan, Italy low-rise steel structure housing 2.1 Japan low-rise steel structure housing Japan industrial housing manufacturers are many, manufacturers continue to research and develop new housing, to meet market requirements, however, the steel structure system is basically the same, but in the roof, wall material selection, indoor and outdoor decoration and equipment are different. Sekisui House Co., Ltd. occupies a leading position in Japan's industrial housing, and the patented prefabricated house Type B inherits the advantages of traditional construction methods, improves the traditional Japanese wood structure house into steel structure and synthetic plate structure, and adopts the modulus of metric integer value. The B-type system provides a variety of free design to meet the different requirements of customers, the main features of the B-type system: (1) the modulus of 1m: steel column spacing 1m, wall panel standard size height 25m, width 2m, middle can be inserted 1m, 0.5m; (2) The skeleton adopts steel structure, and the electrocoating is carried out to improve the anti-rust performance; (3) Wall: lay the plate vertically in the standard-sized steel frame, dry construction; (4) Reinforced concrete strip foundation: using standardized steel formwork, factory-processed steel bars, commercial concrete poured on site, and factory prefabricated foundations are also transported to the site for burial. The following introduces the building structure forms of general Japanese industrial houses: (1) Steel skeleton: the general structural forms include diagonal endurance wall structure, frame structure, frame truss combination structure and plate structure (see).

The steel column of the diagonal endurance wall structure is composed of 32mm C-shaped steel with a thickness of 32mm I-shaped or mouth-shaped section, and H-shaped steel can also be used. The beam is made of H-beam steel with a thickness of 5.58mm. The average amount of steel used in the steel skeleton is 60kg/m2, in order to ensure the strength and rigidity required for use and seismic resistance, the beams and columns are processed with galvanized alloy steel, and then the resin coating is electrocoated after the chemical treatment of iron phosphate film, after such three anti-rust treatments, the weather resistance and durability of the steel structure are greatly improved. When fire protection is required, spray fireproof paint or use plate partitions.

Floor: In addition to sufficient strength and rigidity, its fire resistance, sound insulation, and seismic isolation performance are also important. There are three main types of dry construction methods: (1) wooden keels on steel beams and wooden floors; (2) The steel beam is equipped with secondary beams, steel keels, and paving wood plywood; (3) The steel beams are covered with 100mm thick ALC concrete floor slabs, and then 15mm wooden plywood, carpet or wooden floors. There are also cast-in-place concrete composite floor slabs with profiled steel plates, and heating equipment is set up on the floor slabs. Roof: should be weatherproof, waterproof, leak-proof, thermal insulation, durable and beautiful. The roof is generally made of sloped roof, according to user requirements, the roof panel adopts glazed tiles, stone tiles, colored linoleum tiles, colored steel plate tiles, etc.

It is a type of residential roof construction.

(4) Exterior wall: In addition to meeting the functional requirements of use, the exterior wall panel should also consider industrial production, consider the simple structure of connection with the steel skeleton, and convenient installation on site. There are many types of exterior walls, for example, high-grade ceramic plates and tiles, generally ALC concrete panels, plastic panels, wood panels and colored steel sandwich panels. It is a kind of residential exterior wall structure: (1) 57 thick concrete slabs, the surface can be processed with various patterns; (2) Three anti-rust treatments are carried out on the surface of the steel skeleton; (3) 66mm air layer; (4) 29mm high-performance heat insulation refractory board; (5) 12mm slate.

This kind of exterior wall structure has good durability, high strength, non-flammable, good fire performance, good heat insulation, good sound insulation, and anti-condensation, anti-moisture, and good living comfort.

(5) Doors and windows: most of the windows are double-layer insulating glass, aluminum alloy or plastic doors and windows with good air tightness, which have high strength, good sound insulation performance, and are not easy to condense. Shaded blinds can be set up outside the window. According to the requirements, the door can be made into wooden door, plastic door and steel door, sealed, easy to open, anti-theft, fireproof.

2.2 Italian low-rise steel structure housing Italy BASIS industrial building system is a new type of housing building system jointly researched and designed by New Italian Steel Company and the University of Genoa, and is a newly developed project in the field of steel structure application in Italy. The building system has the advantages of novel shape, reasonable structural force, good seismic performance, fast construction speed, comfortable and convenient living and office, CAD computer-aided design and CAM computer-aided manufacturing. A large number of applications have been promoted in Europe, Africa, the Middle East and other regions, and have been well received. This building system is suitable for the construction of 18-storey steel structure houses. In 1986, the author went to Italy for inspection and visited the construction site of low-rise and multi-storey steel structure houses and processing plants in Italy. The BASIS industrial building system model house given by the Italian manufacturer to the Institute of Metallurgical Construction is in the form of a frame support structure, H-beam H140mmX140mmX7mmX11mm for column meters, 2C280mmX 5mm for large section cold-formed steel for main beam meters, 5mm for secondary beam meters, L75mmX 6mm for angle steel for support meters, and M18mm high-strength bolts for beams and columns through connecting plates. The floor slab adopts 0. Profiled steel plate with dents, the composite floor slab of poured concrete, the stairs are steel stairs (can also be made into concrete cast-in-place stairs) The outer side of the exterior wall structure adopts 80mm thick ordinary concrete precast strip slab (you can also use concrete strip slab, the board surface can be pre-made into various patterns) The exterior wall panel is equipped with embedded parts connected with T-bolts and beams, double-layer sealing strips are provided between the slab seams, the inside of the exterior wall is a 100mm thick glass wool aluminum foil air insulation layer, light steel keel gypsum board, and the column is exactly in the air layer of the inner and outer wall panels. The inner partition wall is made of steel keel, gypsum board, glass wool. The roof is a composite floor, the above is insulated, waterproof, flat roof as a roof garden, doors and windows using SECOL color steel doors and windows and plastic sunshade roller blinds, home has plate type combination furniture, steel combination furniture, lamps, air conditioning, solar energy and other equipment are Italian products. This model house has a construction area of 180m2, all components and equipment, furniture are transported from Italy in 10 containers, the model house is built with 10 people and 40d, and the steel skeleton is only 3d. It is the node structure of the Italian BASIS industrial building system.

3. Several ideas for the development of steel structure housing in China: (1) Deeply understand the national housing industrialization, steel structure housing technology and economic policies. The Ministry of Construction and the State Metallurgical Administration attach great importance to construction steel, and have issued several documents in the past two years, held many meetings, and considered steel structure housing as a key point when drafting iT'15" industrial policies and plans. It is pointed out that the basic development idea of steel structure housing is to lay a foundation and promote development; Second, we must grasp supporting facilities and promote application; Third, it is necessary to grasp the pilot project and bring the industry. It is pointed out that the research of steel structure housing system should be of a high level, in line with China's industrial technology policy, in line with the national strategic policy on going out, in line with the overall requirements of economic development, and from the perspective of market trends. It is required that the steel structure house should be people-oriented, and the starting point should be high in terms of research, design, materials, accessories and processing technology, construction and management. Steel structure housing should be recognized and satisfied by users with its applicability, safety, durability, environmental and economic performance and other excellent residential performance, in addition, to research and develop steel structure housing suitable for China's national conditions, suitable for different consumer groups with local characteristics of steel structure housing system.

Increase the intensity of research on steel structure housing system. The Ministry of Construction vigorously promotes the research and development of steel structure houses in various provinces and cities and large enterprises. Scientific research and design units should support enterprises to continuously improve, gradually improve, and do a good job in their respective steel structure housing systems. Develop low-rise, multi-storey and small-high-rise steel structure residences to meet the different requirements of the market. For steel structure housing, the structure is only a skeleton, and there are many supporting materials and related technologies to be solved, for example, the more prominent problem is that the wall materials are not matched. The steel structure housing system must consider the coordinated development and scientific and technological innovation of related enterprises. At present, the rolled H-beam steel for China's steel structure residential skeleton has been produced in Ma Steel, Lai Steel, Angang, Shanghai Datong high-frequency welding H-beam, Qinhuangdao, Wuhan cold-formed rectangular steel pipe and dozens of welded H-beam production lines and cold-formed steel production lines across the country, providing a variety of steel for steel skeletons; All forms of roofing, profiled steel plate, ALC board, space board, SP board, glass wool, polyurethane board, gypsum board, fireproof board can be produced; All kinds of bolts, self-tapping screws and waterproof sealing materials are available; There are imported plumbing and electrical equipment, and some are domestic. At present, the main problem is how to make these building components and parts well combined through design research, so as to meet the requirements of residential performance, convenient construction and installation, and can finalize design standards and factory production of components. New residential products should be tested as a whole on the basis of material and component tests, summarize experience, improve and improve to form a relatively mature residential product, and then put on the market after appraisal by relevant departments. Establish a perfect after-sales service system to make users rest assured.

Steel structure residential building system can be studied according to low-rise, multi-storey, small high-rise and high-rise classification, Japan calls 23-story villa buildings industrialized housing, which is now becoming more and more perfect, and can be personalized for users on the basis of standard stereotyping. In the mid-80s of the 20th century, China introduced more than 200 villas from Japan for foreigners to live, and the demand has increased in recent years, with the improvement of national living standards, suburban villas and country houses have become the choice of some consumers. The steel structure housing system can provide ideal housing for this part of the consumer group.

The

inhomogeneity coefficient is calculated by taking 1.2 3 internal forces of the structure 31 The structural displacement calculation is calculated and the whole structure is divided into equal column elements, equivalent column elements and floor beam elements according to the cross beam system, and the matrix displacement method is used to calcate.

The element stiffness is calculated using Equation (3), Equation (6), and Equation (7).

Solving equation (8) yields the displacement y/ sum of the first floor of the ith anti-lateral force structure.

After finding the shear force and bending moment of each wall limb of the shear wall

at the floor, the shear force and bending moment of the connecting beam can be obtained from the nodal balance condition and the linear stiffness of the connecting beams on both sides of the wall limb.

For the underlying frame column, after finding the displacement and rotation angle of the vertex, the shear force and bending moment of each column can be obtained according to the ordinary member. The axial force of the first column of the i-piece frame support wall can be calculated according to equation (14): the corner of the ground floor of the i-piece frame support wall.

After finding the internal force of the

underlying frame column, the internal force of the frame support beam can be obtained according to the balance conditions of the frame node.

For a floor with an endpoint k, the shear force can be calculated as follows: 4 The epilogue is limited to space, and no examples are given in this article. The examples that the author has made show that the method in this paper can be applied to the calculation of the internal force of the frame support shear wall structure, which can not only consider the deformation of the floor, but also apply to the situation of the vertical stiffness change of the structure. There are few degrees of freedom and sufficient calculation accuracy.