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Development Trend of China Steel

( 1 ) the development and application of high -quality high-strength low-alloy steel
Currently, in addition to steel Q235, Q345, Q390, Q420 specifications in the newly added steel , but its steel application needs further study . In order to meet the needs of development , China 's iron and steel structural steel in the future development and application , but also the need to strengthen the following aspects:
1 ) the development of higher strength, better overall performance of low-alloy structural steel.
2 ) to increase the production of low -alloy steel and steel application rate.
3 ) improve and enhance the quality of low-alloy steel .

( 2 ) Design Theory and Methods

Ensure the safety of the structure in order to give full play to the role of steel, more rational use of steel, structural design theory and methodology , calculation methods, structures and components should also be further studied under real working conditions should reflect the premise. Open research question is: bending bending element torsional buckling problem , utilization after bending sheet strength , steel plastic design issues , the impact of structural strength lightweight steel portal frame system and the stability of the work space and overall stability of the structure of the problems , and the like.
( 3 ) research and application of light steel
Light steel structure mainly refers to the thin-walled steel , mild steel and light steel bar by the small angle . Since the 1960s, the systematic study of thin-walled steel structures for roof trusses and purlins bearing structures and bulk , such as to encourage the development of light steel structure .

Steel and concrete ( 4 ) research and applications of composite parts
Steel and concrete composite members take full advantage of the characteristics of tensile stress of steel and concrete , so that a component has a variety of uses, so it is a very rational economic structure , has been used in bridges and house floor. For example, the House floor beams and reinforced concrete composite structure with steel stamping die at the bottom of the application , and then use the Cut button ( common wire nail ) is connected to the concrete slab , steel stamping and concrete slabs to make the overall composite panels , steel underground concrete structures this structure is used in the construction of a very promising form of components , the need for further research and development.
( 5 ) high-rise steel research
In recent ten years , China's coastal cities to establish a large number of high-rise buildings , some of which mixed with steel or reinforced concrete structural system of steel tubular frame combination . But basically, the buildings built on attracting foreign investment , and designed by foreign designers , production and installation process at home , entirely designed high-rise steel works at home rarely . Therefore , China is still a lack of high-level experience in the design of steel , compared with developed countries in the theoretical study there is a gap, we must strengthen the research work in the future .
Research and Application ( 6 ) spatial structure
Grid structure , lattice shell structures , tensile structures belong to the spatial structure of the system , the application of new technologies to reduce the structural weight , improve the bearing capacity of the structure , such as steel saving effect is very obvious .
In addition, pre-stressed steel can improve structural rigidity , increase the carrying capacity , thereby saving steel. Can be applied to prestressed structural steel trusses, beams and frame structures or components, but seldom used , which is needed in research and development .
( 7 ) Steel corrosion and fire
Steel corrosion and fire , has been a problem and needs to take care of the steel structure design, is still not very effective measures. Therefore, fireproof and maintenance cost a lot still needs to increase the steel structure and maintenance costs .
( 8 ) the development and application of steel design software
Computer technology has been widely used in civil engineering, computer-aided design (CAD computer-aided design ) optimized structure design played a huge role in improving the design efficiency. At present , China has independently developed a lot of sophisticated structural design software , there are steel design software , but the development of the steel structure , steel structure design software also needs to constantly improve and perfect .