Numerical Case Studies about Two-Dimensional CHS Joints with Symmetrical Full-Overlapped Top-Connection

Area of Science:

• Structural Engineering
• Mechanical Engineering
• Materials Science

Background:

• Circular hollow section (CHS) steel joints are vital in constructing large-span structures like airport halls.
• The nodes in ramified vertical columns, formed by connecting inclined pipes to a vertical one, represent structural weak points due to geometric complexity.
• Existing design codes inadequately address the unique geometrical properties and limitations of these atypical CHS joints.

Purpose of the Study:

• To numerically investigate the structural resistance of atypical two-dimensional CHS joints.
• To analyze the influence of geometrical parameters, specifically the inclination angle between members, on joint behavior.
• To evaluate the stability and load-carrying capacity of these non-standard steel joints.

Main Methods:

• Finite Element Analysis (FEA) was employed for numerical case studies.
• A small-scale model was initially analyzed to understand the effect of inclination.
• The study progressed to extended pipe geometries to assess broader behavioral changes.

Main Results:

• The inclination angle between the pipes critically affects stresses and deflections at the joint node.
• An increased inclination angle leads to a higher maximum applied force capacity.
• Modifications in member geometry alter the joint's behavior and stress distribution patterns.

Conclusions:

• The inclination angle is a key design parameter for atypical CHS joints, directly influencing structural performance.
• FEA provides a viable method for assessing the resistance of CHS joints excluded by current standards.
• Further research into extended member geometries can optimize the design of these critical structural components.