Bolted connection is one of the most widely used connection methods in steel structure engineering. According to load-bearing characteristics, installation requirements and applicable scenarios, it is mainly divided into the following types:
Common Bolt Connection: This is the most basic and common bolt connection method. After installation, the tightening force of the nut is mainly provided manually, and the transmitted load is relatively small. This connection is mainly used for structural parts with small and stable loads, such as temporary works, auxiliary structures and non-load-bearing components.
High-Strength Bolt Friction-Type Connection: High-strength bolts are pre-tensioned with special wrenches or electric tools to produce strong preload, clamping the connecting plates tightly. Loads are transmitted through friction between the contact surfaces, and no relative slip occurs between plates under normal service conditions. This connection has excellent seismic performance and is mainly used for structural parts with large loads, frequent load changes and high reliability requirements, such as key joints of main steel structures.
High-Strength Bolt Bearing-Type Connection: Different from the friction-type connection, under load, the bearing-type connection transmits part of the load through friction, and mainly relies on the shear force of the bolt shank and the bearing capacity of the plate hole wall. In this connection, the contact surfaces between bolts and connecting plates must be clean, free of grease, paint, rust and other impurities, otherwise the bearing performance and stability will be affected.
Anchor Bolt Connection: This method is mainly used to fix steel structural members to concrete foundations or other load-bearing bases, and is the core connection between steel structures and foundations. Anchor bolts are pre-embedded during concrete pouring. After the concrete reaches design strength, steel members are connected and fastened to the anchor bolts to ensure overall stability.
These are the common types of bolt connections for steel structures. Different connection methods differ in mechanical performance and application scenarios, so they should be selected reasonably according to actual engineering needs.
When selecting and applying bolt connection methods for steel structures, the following factors should also be considered comprehensively:
Structural Requirements: Choose the appropriate connection according to the load condition, magnitude and frequency of the structure. For example, high-strength bolt connections (friction-type or bearing-type) should be used for parts with large loads, frequent load changes or high seismic requirements. For temporary works, auxiliary structures or non-load-bearing members, common bolt connections are usually sufficient.
Installation Conditions: Space and equipment on site affect the selection. In narrow spaces where electric tools cannot be used, manually installed common bolts can be chosen. Where conditions permit, high-strength bolts are preferred for superior connection performance and structural safety.
Cost Considerations: Material and installation costs of high-strength bolts and anchor bolts are usually higher than common bolts. With limited budget, balance cost and performance to select the most cost-effective method without compromising safety.
Maintenance Considerations: Maintenance difficulty and frequency vary between connection types. High-strength bolt connections require regular inspection of preload and retightening if loose. Common bolt connections are simpler, only needing periodic checks for rust and loosening.
In summary, the selection of bolt connection methods for steel structures must comprehensively consider structural requirements, installation conditions, cost control and maintenance convenience, while strictly complying with relevant design codes and safety standards to ensure safe, reliable and durable connections.If you need steel structure bolts or related connection solutions, please feel free to contact us.
