Definition and Key Feature

Rigid tie rods are longitudinal structural members that can resist both tension and compression, distinguishing them from flexible tie rods (e.g., round bars, cables, or wire ropes) which are tension-only. This dual capability makes them critical for force transmission in steel portal frame buildings.

Mandatory Installation Locations

Rigid tie rods must be installed at the following positions:

☆Frame inflection points – at the roof ridge and column tops (both external and internal), running continuously along the full building length.

☆Braced bays – at nodes of roof horizontal bracing and column bracing.

☆Ends of temperature zones – when bracing is placed in the second bay, the first bay must receive supplemental rigid tie rods at corresponding locations.

☆Crane beam elevations – in buildings with overhead cranes, longitudinal rigid tie rods are required continuously at this level.

Structural Function

Each temperature zone functions as an independent stable system. Braced bays are equipped with rigid tie rods, while intermediate bays may use flexible tie rods for lateral restraint.

The primary role of rigid tie rods is to collect and transfer longitudinal forces – including gable wind loads, seismic forces along the building axis, and crane-induced longitudinal loads – through the tie rods into the bracing system, and ultimately to the foundations. This clear load path ensures overall structural stability under horizontal actions.

In summary, proper placement of rigid tie rods is essential for safely transmitting longitudinal forces in portal frame buildings.

For more information needed or any inquiry,please feel free to contact Yumisteel team.