In the whole process of steel structure design, we should pay attention to conceptual design.It is particularly important in the stage of structure selection and layout.Some of them are difficult to make accurate and reasonable analysis, or based on unclear specifications and mechanical relations, from the overall system structure and system damage mechanism, damage design, test phenomenon and engineering experience, from the overall layout and the detailed measures to determine the control structure.The use of conceptual design can be quickly and effectively conceived, compared and selected in the early stage.The calculation of the structure is simple and accurate, avoiding unnecessary operation in the structural analysis stage.At the same time, it is also the main basis to judge whether the output data of computer internal force analysis is reliable.

         In the practical design of steel structure, the structural analysis is usually linear elastic analysis, and P △ and P △ are considered when conditions permit.

          Some recent finite element software can consider the geometric nonlinearity and elastoplasticity of steel.This provides conditions for more accurate analysis of the structure.Not all structures require software: a typical structure can check the internal forces and deformations of reference books, such as mechanical manuals.The simple structure is analyzed by hand algorithm.The complex structure needs to be modeled and analyzed in detail.

          The two stages of steel structure design drawing and detailed drawing are designed for steel structure.Design drawings are provided to design units, mainly schematic drawings and bar diagrams.The detailed construction drawing is usually made by the professional steel structure manufacturing company, and the detailed design content is carried out according to the design drawing.Now the design program and advanced deepening can complete the processing and production of all rods and other contents at the same time.Sometimes it is replaced by a design unit.Due to the increasing number of steel structure projects in recent years, steel structure engineers are lack in design institutes, and the ability of steel structure enterprises to participate in design drawings is also very common.