How to design a built-up compression member|| what are built-up section? And explain the shear connections between the element of built-up member|| snug-tight connection & welded connection
Snug Tight Connection:
- A snug tight connection is a type of bolted connection where the bolts are tightened to a snug position, but not overtightened.
- The connection is designed to provide a firm connection between the components, but still allow for some minor movement or settlement.
- Snug tight connections are typically used in compression members where the loads are relatively low to moderate.
Tight Connection:
- A tight connection is a type of bolted connection where the bolts are tightened to a higher torque value than a snug tight connection.
- The connection is designed to provide a more rigid connection between the components, with minimal movement or settlement allowed.
- Tight connections are typically used in compression members where the loads are moderate to high.
Weld Tight Connection:
- A weld tight connection is a type of welded connection where the welds are designed to provide a high-strength, rigid connection between the components.
- The welds are typically made with a high-strength filler metal and are inspected to ensure their integrity.
- Weld tight connections are typically used in compression members where the loads are high to very high.
In compression members, the type of connection used depends on the magnitude of the loads, the type of loading (e.g., axial, eccentric), and the required level of stability. Generally:
- Snug tight connections are used for lower load levels and where some minor movement is acceptable.
- Tight connections are used for moderate load levels and where minimal movement is allowed.
- Weld tight connections are used for high load levels and where a high-strength, rigid connection is required.
Keep in mind that these explanations are generalizations, and specific design requirements may vary depending on the project and applicable codes and standards.
Built-up Section Examples:
- Built-up beams (e.g., I-sections, box sections)
- Built-up columns (e.g., hollow sections, lattice columns)
- Built-up trusses (e.g., Warren truss, Pratt truss)
Built-up Member:
- A built-up member is a structural element composed of multiple components (e.g., plates, angles, channels) connected together to form a single member.
- Built-up members are used to resist various types of loads (e.g., axial, bending, torsion).
Shear Connections:
- Shear connections are used to connect built-up members to transfer shear forces between components.
- Types of shear connections:
- Bolted connections
- Welded connections
- Riveted connections
Effect of Spacing of Shear Connection:
- The spacing of shear connections affects the structural behavior of built-up members.
- Closer spacing:
- Increases the strength and stiffness of the member
- Reduces the slenderness ratio and potential for buckling
- Wider spacing:
- Reduces the strength and stiffness of the member
- Increases the slenderness ratio and potential for buckling
In general, the spacing of shear connections should be optimized to achieve the required structural performance while minimizing material usage and construction costs. The specific spacing requirements will depend on the type of built-up member, loading conditions, and design codes.
