Limiting conditions for connection design of steel structural members

【概要描述】 1. Source of constructionTheoretically, steel structural members or connecting members have arbitrary processability, but in each specific project, structural members and connecting members are always restricted by practical conditions. Experienced designers usually choose sections that are easy to

1. Source of construction

Theoretically, steel structural members or connecting members have arbitrary processability, but in each specific project, structural members and connecting members are always restricted by practical conditions. Experienced designers usually choose sections that are easy to obtain and install, and design simple and effective connection methods and connecting components.

2. Restrictions on linking means

One of the construction characteristics of steel structure is factory processing and on-site assembly. This is different from the traditional masonry method and produces a large number of joints. There are three main means of connection between various section steels: riveting, welding and bolting. Riveting is often used in the early stage of steel structure buildings. The construction is simple, but it needs to dig holes in the components, which reduces the section performance and is easy to produce concentrated stress at the joints. It is rarely used recently. Welded joints have simple appearance and continuous load transfer efficiency, but the construction requirements are high. The high-strength bolt connection in the later stage can also meet the strength requirements of similar welding, which is widely used in modern steel structures.

3. Link components are hierarchical

There is a complex and logical hierarchical relationship between steel structure and building structure system. At the connection level, this hierarchical relationship is reflected in the difference between component size and installation sequence. The purpose of connection is to realize the hierarchical transformation, and it is also the key to realize the transformation of force from three-dimensional to two-dimensional and finally transferred to one-dimensional components. Complex connection is usually completed by the combination of three-dimensional connection components and plane connection components.

4. The plane where the link is built

Two linear structural members are always in a plane, which is the plane of component stress. In order to effectively resist the stress, bending moment or shear force in this plane, the connecting members are often designed in this plane. For example, the welding pieces of steel pipe and stay cable are always in the plane composed of the two; In the case of the connection of multiple components, the combined plane components can correspond to the three-dimensional stress.