Three Questions and Three Answers to Prefabricated Steel Structures

1、 What are the structural systems for the construction of prefabricated steel structures? How high can we do it? How much steel is used?

The construction of prefabricated steel structures has a rich range of structural systems to meet different construction requirements, including structures, structural supports, structural shear walls, etc.

In terms of materials, various forms such as pure steel structure systems and steel tube concrete composite structure systems can be selected. The height of prefabricated steel structure construction can reach all the construction heights available in the current construction field.

Almost all super high-rise buildings use steel structural systems (or partially use steel structural components). Generally speaking, according to the increase in construction height, a system with strong lateral force resistance needs to be selected.

For residential buildings, multi story structures below 6 floors often use pure structural structures, with a steel consumption of approximately 70-80kg/square meter;

High rise structures with 6-18 floors often use structural support structures, with a steel consumption of approximately 80-90kg/square meter;

In addition to structural support, structural shear walls and other systems can also be used for high-rise buildings with 18-30 floors, with a steel consumption of approximately 90-110kg/square meter.

2、 What are the wall panels used in the construction of prefabricated steel structures? How to solve the problem of deformation coordination? Are there any cracks in the wall panel? Is there a problem with poor sound insulation?

The construction of prefabricated steel structures is mainly based on steel structures, which can match various wall panel components according to construction needs, such as lightweight strip concrete PC panels and glass aluminum panel walls.

At present, steel structures often use lightweight strip ALC boards as filling walls for external or internal walls. The combination of this type of plate and steel structure is widely used in construction in Japan. The application in domestic engineering is also increasing, such as the China Zun project. This type of wall panel material, like autoclaved aerated blocks, belongs to the same category as concrete products.

The internal reinforcement of the wall panel has high strength; Lightweight material, relatively low density, easy to transport and install; The internal porous structure has good insulation and sound insulation effect.

According to the standard atlas, the ALC strip has various node connection methods such as hook head bolts, sliding S-plates, and built-in anchors, which can meet the structural deformation requirements with interlayer displacement angles ranging from 1/50 to 1/200.

According to research, the problem of cracks in wall panels is mainly caused by the drying shrinkage of materials. Cracking in the coating layer of wall decoration can be avoided by controlling the moisture content of the wall panel and adding anti crack tape during the decoration process.

The sound insulation effect of ALC wall panels is very good. It is recommended to use 200mm thick wall panels for household walls, with a sound insulation of up to 47-48dB. 100mm thick wall panels can be used for room walls, with a sound insulation of up to 42-43dB.

The insulation and exterior decoration of prefabricated steel structures can use traditional thin plastering systems, dry hanging curtain wall systems, or insulation and decoration integrated panel systems.

The waterproofing of thin plastering and curtain wall systems is consistent with traditional practices. The waterproofing of insulation and decoration integrated panels is achieved by combining various measures such as sealing materials and waterproof strip construction to prevent external wall leakage.

3、 What are the floor slabs used for the construction of prefabricated steel structures?

The construction of prefabricated steel structures should use profiled steel plates, steel bar trusses, or composite floors with detachable steel bar trusses.

In the case of public building rooms with suspended ceilings, it is recommended to choose a composite floor slab consisting of profiled steel plates and steel truss floor support plates. The galvanized surface of the floor support plate can be covered by the indoor ceiling.

In the absence of suspended ceilings in residential construction rooms, it is recommended to use detachable steel truss floor support composite slabs. After pouring concrete, the bottom formwork is removed, and the finished surface is very good, allowing for direct putty and coating construction.

We do not advocate the use of precast concrete composite panels, which are heavy in weight and seriously occupy on-site lifting equipment. The device efficiency is low, and the lower part requires a large amount of support, accompanied by additional processes such as installation and dismantling of support and safety hazards.