The Common Types of Steel Connections

Introduction

This tutorial provides an overview of the common types of steel connections used in structural engineering. Understanding these connections is crucial for designing steel structures effectively, as they play a significant role in transferring loads and moments. Each connection type has its own advantages and disadvantages, which are essential to consider when planning a project.

Step 1: Understand Connection Categories

Steel connections can be categorized into four main types:

1. Pinned connections
2. Semi-rigid connections
3. Fixed connections
4. Bearing connections

Recognizing these categories helps in selecting the appropriate connection type based on the structure's requirements.

Step 2: Explore Welded and Bolted Connections

There are two primary types of connections:

• Welded Connections

  • Allow for direct joining of members, enabling moment transfer.
  • Can be time-consuming and costly, especially if on-site welding is required.

• Bolted Connections

  • Generally preferred for quick assembly.
  • Typically less expensive and easier to work with on-site.

Understanding the differences between these connection types is crucial for optimizing construction efficiency and cost.

Step 3: Learn About Common Connection Types

Fin Plate Connection

• Utilizes a plate with bolts in line.
• Number of bolts is typically determined by dividing the member's depth by 100.
• Commonly used for simple or pinned connections, with limited moment transfer.

Bearing Connection

• Involves a beam resting on a top plate of a column.
• Can be pinned, semi-rigid, or fixed, depending on stiffness.
• Gusset and stiffener plates may be used to enhance rigidity.

End Plate Connection

• Similar to bearing connections but requires precise lengths for beams.
• Limited tolerance can complicate construction.

Splice Connection

• Used to join two members, either through welding or bolted connections.
• Requires careful design to handle moment forces effectively.

Step 4: Consider Bolt Types

Different bolt types affect connection performance:

• S Bolts: Standard bolts that allow for some slip.
• TB Bolts: Friction bolts that limit slip, but reduce shear resistance when tightened.
• TF Bolts: Require surface roughening for friction; used in specific locations where slip cannot be tolerated.

Choosing the right bolt type is essential for ensuring structural integrity.

Step 5: Implement Haunch Connections

In larger structures, haunch connections are often used:

• Increases connection depth to enhance stiffness.
• Helps manage moments and deflections effectively.

Using these connections can improve overall structural performance.

Step 6: Address Special Connection Needs

For connections needing to transfer lateral forces without moment transfer, consider:

• Fin Plate Connections with Slotted Holes: Allow vertical movement while resisting lateral forces.
• Double Plate Connections: Increase thickness in critical areas to handle higher forces.

These specialized connections offer flexibility in design while maintaining structural integrity.

Conclusion

Understanding the various types of steel connections and their applications is vital for structural engineers. By choosing the right connection type and bolt configuration, you can optimize the design and functionality of steel structures. Consider exploring additional resources and tutorials on steel design principles to further enhance your knowledge and skills in this area.