Steel structure has the advantages of high strength, light weight and excellent mechanical function. Therefore, steel structure is a kind of structure to observe the reality. Especially, the development of modern architecture is more and more in the direction of “high, precise and deep”. Steel structure just can deal with the problems that reinforced concrete structure can’t handle in the past, so steel structure is more and more widely used.However, due to the small section area of steel structure, in order to improve the rigidity of the section, the section of steel structure is often designed as thin-walled and developed section from the perspective of economic hardness. Therefore, compared with reinforced concrete structure, the stability is the most important form of steel structure design, and even the decisive element, while the elements without stability are various, and some are uncertainOur design is based on many assumptions.In addition, the section composition and connection form of steel structure is much simpler than that of reinforced concrete structure. Therefore, the design idea of steel structure plays an important role in the design.

Steel structure design should be the first to judge whether the structure can be used for steel structure. At present, steel structure architecture is changing into a kind of architectural fashion. Modern observation of famous buildings simply cannot do without steel knot sentences.Although the steel structure has many advantages, but the profit is high, and it is not fire-resistant. Once a fire occurs, the measurement is better than 600u, and the steel structure will get the bearing capacity completely.Generally speaking, high-rise buildings, large-span buildings, simple shapes, buildings that accept large dynamic loads, high sealing requirements, and buildings that request to be able to move and install or dismantle, etc., are mostly steel structures, but steel structures are not suitable for general multi-storey residential buildings.

In a certain process, “conceptual design” should be emphasized, especially for some problems that are difficult to be analyzed accurately or with irregular standards, which can be based on the mechanical connection between the whole structural system and the analytical system, the destruction mechanism, the earthquake damage, the experimental reason and the lost design of the engineering experience.From the overall hardness, we can definitely grasp the structure deployment and detailed measures.In a word, it is necessary to choose a reasonable structural plan, a practical structural mode and system, and to be able to observe the operation of more plans and select the best when it is redundant.After the structure is sure to go up, it is necessary to make a preliminary budget for the cross-section of the component. The key is the assumption of the shape and size of the cross-section of beam, column and support.For example: steel beam can choose channel steel, H-section, etc.The height of the beam section can also be chosen between L / ’20 and L / 50 of the span.In particular, we should pay attention to the opposite structure. In the standard, there is a great opposite to the section construction request. For example, all the stability problems of the special parts of the steel structure constitute the members. In the general steel standard and the light steel standard, the limit value is very different. At present, when the above forms are realized, the selected structure should be operated for structural analysis and engineering judgment.Easy structure can be analyzed by hand operation structure. Simple structure needs to model operation procedure and make detailed structure analysis.There is a definite interval between the intention in engineering design and the accurate mechanical intention. In order to lose the applied design method, sometimes the assumption with large error is used, even some engineering budget or some experience method is used. Although in the design, this error will be guaranteed by “practical conditions, concepts and forms of construction”, the concept design should be emphasized here”And engineering discrimination