We believe that the problems and difficulties in the promotion of steel structure housing in my country are mainly in the following aspects: (1) The degree of industrialization of supporting parts is low. Steel structure housing is a complex integration of technology, parts and materials. It is the discovery direction and inevitable product of the gradual modernization of the housing industry. Therefore, steel structure housing must first be industrialized. However, at present, the technically mature parts and accessories related to steel structure houses are either lacking, or have a low degree of industrialization, or lack technical standards or are inconsistent with the relevant standards of steel structure houses, especially walls, floors, balconies, stairs, etc., wet work More, resulting in the current steel-structured houses are basically in the embarrassing situation of "wearing a T-shirt and a tie". (2) The lack of modularization seriously restricts the industrialization development of steel structure housing. At present, there are only modular standards for stairs, doors and windows, kitchens and bathrooms, and there is still a lack of unified modular standards for most parts and components such as roofs, partitions, and elevators. (3) Steel structure design optimization, such as building plane and column network optimization, cold-formed rectangular tube instead of welded box column, variable section column application, buckling restraint support application, etc., reduce engineering costs and improve steel structure housing economy. 3.1 For the current various structural systems, their scope of application has not been clearly specified, and there is no design reference basis. Therefore, the current structure selection can only be based on the mechanical performance of the structure, with the goal of reducing the amount of steel used, and meeting the constraints of architectural design to obtain qualitative conclusions. In the structural design, the project cost can be effectively reduced by optimizing the design. This process is cumbersome and complicated, and the structure and the building need to be coordinated. At present, this work still has a long way to go. 3.2 The research on new beam-column joints can further reduce the cost of manufacture and transportation. In the national architectural standard design atlas "Steel Structure House (2)" (05J910-2), only 7 kinds of common beam-column joints are given, the new type of diaphragm through joints, sleeve-type reinforced joints, external ribs Ring plate nodes, etc. are not listed. In addition, in terms of the force transmission characteristics of the joints, the selection of joint forms (rigid, semi-rigid, hinged) should also be combined with actual calculation and comparison, and the optimal joint form can be selected, which can further reduce the amount of steel used, but the current specifications (such as GB50017- 2003) has a lot of lag and lacks the criterion for rigid, semi-rigid and hinged joints and the calculation basis for semi-rigid joints.

(4) The lack of design specifications has led to some new high-quality steels not being promoted or problems such as inferior use of high-quality materials. For example, the current "Code for Design of Steel Structures" (GB50017-2003) and "Technical Specifications for Steel Structures of High-rise Civil Buildings" (JGJ99-98) do not list high-rise steel and weathering steel as recommended materials, nor give corresponding instructions, so that in the This type of steel cannot be used in the design or the strength of high-quality Q345GJ steel is taken as the value of ordinary Q345 steel. (5) Corrosion problems. The current "Code for Design of Steel Structure" (GB50017-2003), "Code for Design of Industrial Building Anti-corrosion" (GB50046-2008), "Code for Acceptance of Steel Structure Construction Quality" (GB50205-2001), etc. The design life is clearly stipulated. Even the newly published "Code for Design of Steel Structure Residential Buildings" (CECS261-2009) only makes general provisions on the number and thickness of anti-corrosion coatings, and its anti-corrosion effect and maintenance cycle lack clear standards. Require. In addition, since most of the steel components of the steel structure house are hidden in the wall, its anti-corrosion coating maintenance is very difficult, the maintenance is difficult, and the cost is high. At present, the regular inspection and maintenance requirements usually mentioned in the design description are vague and difficult to achieve. . (6) Application of high-strength steel. The third paragraph of 3.9.2 of "Code for Seismic Design" (GB50011-2010) puts forward clear requirements on the material properties of steel for steel structures: "The yield ratio of steel should not be greater than 0.85; the steel should have obvious yield steps, and the extension The length should not be less than 20%; the steel should have good weldability and qualified impact toughness." Due to these requirements, the current strength of steel used in my country's steel structure is only about Q460, and the research and development of high-performance steel with higher strength and meeting the requirements of the specification imminent. In addition, the steel rolled by TMCP technology also puts forward higher requirements for welding technology. (7) The detail treatment process needs to be improved. Due to the large ductility of the steel structure itself, some of the joint forms commonly used in the industry, such as slats, whole slabs, blocks, etc., cannot adapt to the deformation of the structure itself, and there are cracks and leakages in the slab joints. And other issues. In addition, further research is needed on the sound insulation treatment of steel structure houses. (8) The quality of the construction team needs to be improved urgently. The development of steel structure housing is standardized design, factory production, and on-site assembly construction, which is completely an industrialized development model, which requires a high-quality professional construction team. However, most of the current steel structure engineering construction still follows the traditional extensive management mode, and the professional skills of personnel are mixed, which makes it difficult to meet the needs of industrial production, especially in the modules such as "three-board" installation, structural installation, equipment and pipeline installation, and overall kitchen and bathroom. The problems of chemical installation and other aspects are particularly prominent, the advantages of construction speed cannot be brought into play, and more seriously, it affects the construction quality and the promotion of steel structure houses. industrial workers and a professional construction team. (9) Lack of national policy support measures. Since 1996, the state has successively issued a series of steel structure buildings such as "1996-2010 Construction Technology Policy", "Notice on Further Doing a Good Job in the Promotion and Application of 10 New Technologies in the Construction Industry", and "Green Building Technology Guidelines". Technical standards, norms and policies have guided and promoted the development of steel structure housing to a certain extent, but there is a lack of specific support policies that can directly motivate developers, such as science and technology demonstration projects of the Ministry of Construction, green demonstration projects, etc. There are no technology subsidies. In the initial stage of the development of steel structure housing, the degree of industrialization and standardization is not high, and the cost of research and development, promotion and application is relatively high. The enthusiasm and market competitiveness of steel structure housing.