Summary of Basic Knowledge of Steel Structures

1、 The characteristics of steel structure:

1. The steel structure has a relatively light self weight

2. High reliability of steel structure work

3. The steel has good vibration (shock) resistance and impact resistance

4. The industrialization level of steel structure manufacturing is relatively high

5. Steel structures can be installed accurately and quickly

6. Easy to make into a sealed structure

7. Steel structures are prone to corrosion

8. Poor fire resistance of steel structures

2、 The grades and properties of commonly used steel structures

1. Carbon structural steel: Q195, Q215, Q235, Q255, Q275, etc

2. Low alloy high-strength structural steel

3. High quality carbon structural steel and alloy structural steel

4. Special purpose steel

3、 Principles for selecting data for steel structures

The principle of selecting data for steel structures is to ensure the load-bearing capacity of the load-bearing structure and prevent brittle failure under certain conditions, taking into account factors such as the importance of the structure, load characteristics, structural mode, stress status, connection methods, steel thickness, and working environment.

The four types of steel models proposed in the "Code for Design of Steel Structures" GB50017-2003 are "suitable" for use, and are the first choice when conditions permit. The use of other models is not prohibited, as long as the steel used meets the requirements of the specification.

4、 Primary Steel Structure Skills Content:

(1) High rise steel structure skills. According to the construction height and design requirements, frames, frame supports, tubes, and mega frame structures can be used, and their components can be made of steel, reinforced concrete, or steel tube concrete. Steel components are lightweight and have good ductility, and can be made of welded or rolled sections, suitable for construction of ultra-high floors; Stiffened reinforced concrete components have high stiffness and good fire resistance, making them suitable for mid to high rise construction or bottom structures; Steel tube concrete construction is simple and only used for column structures.

(2) Space steel structure skills. The spatial steel structure has light weight, high stiffness, beautiful appearance, and fast construction speed. The spherical node flat grid, multi-layer variable cross-section grid, and grid shell with steel pipes as members are the most commonly used structural types of spatial steel structures in China. It has the advantages of high spatial stiffness and low steel consumption, and can provide comprehensive CAD in design, construction, and inspection procedures. In addition to grid structures, spatial structures also include large-span suspension structures, cable membrane structures, etc.

(3) Skills in light steel structures. Accompanied by a new structural approach consisting of lightweight colored steel plates for wall and roof enclosure structures. A lightweight steel structural system consisting of large cross-section thin-walled H-shaped steel wall beams and roof purlins welded or rolled with steel plates of 5mm or more, flexible support systems made of round steel, and high-strength bolts. The column spacing can range from 6m to 9m, the span can reach 30m or more, and the height can reach more than ten meters. It can also be equipped with a lightweight crane. The amount of steel used is 20-30kg/m2. There are now standardized design procedures and specialized production enterprises, with good product quality, fast installation speed, light weight, low investment, and construction not limited by seasons, suitable for various light industrial factories.