The Main Differences Between Steel Structures

There is indeed no unified standard for determining whether a structure is heavy steel or light steel. Many experienced designers or project managers often cannot fully explain it, but we can comprehensively consider and judge it based on some data:
1. The weight of the crane hoisting in the factory building: greater than or equal to 25 tons, it can be considered as a heavy steel structure.
2. The amount of steel used per square meter: greater than or equal to 50KG/㎡, it can be considered as a heavy steel structure.
3. The thickness of the steel plate of the main component: greater than or equal to 10MM, which is less used in light steel structures.
In addition, there are some reference values: such as the cost per square meter, the maximum component weight, the maximum span, the structural form, the eaves height, etc. The above can provide empirical data when judging whether the factory building is heavy steel or light steel. Of course, many buildings are both light and heavy steel. But there are some that we can say with certainty that they are heavy steel: such as: petrochemical plant facilities, power plant buildings, large-span stadiums, exhibition centers, high-rise or super-high-rise steel structures.
In fact, there is no such thing as heavy steel in national standards and technical documents. In order to distinguish light house steel structures, it may be more appropriate to call general steel structures "general steel". Because the scope of ordinary steel structure is very wide, it can include various steel structures, regardless of the load size, and even include many contents of light steel structure. The technical regulations for light steel structure of houses only stipulate some more specific contents for its "light" characteristics, and the scope is limited to single-layer portal frames.
Light steel is also a relatively vague term, and there are generally two understandings. One is the "Light Steel Structure of Round Steel and Small Angle Steel" in Chapter 11 of the current "Steel Structure Design Code" (GBJ 17-88), which refers to light steel structures made of round steel and angle steels smaller than L45*4 and L56*36*4.
It can be seen that the difference between light steel and heavy steel is not the weight of the structure itself, but the weight of the enclosure materials it bears, and the concept of structural design is still the same.