Project Scope:
• EDC was engaged to investigate a long-standing structural vibration issue that was causing cracking failures in the Primary Sizer and the whole of building structure.

Challenge:
• Identify and quantify dynamic excitation crushing and impact forces that were being developed within the sizer, and produced significant broad band energy, sub-20Hz frequency.
• Traditional structural design changes were simply not going to achieve an acceptable vibration outcome, forcing innovative design.

Outcome:
• EDC determined the source of force excitation was predominately from large rocks impacting the sizer teeth, and then they would repeatedly bounce (balling) on the crusher teeth until crushed
• A 200T heavy mass isolation frame with air operated absorbers was designed and developed.

Success:
Through complex measurements taken in an extremely harsh environment, dynamic simulation of measured loading and frequency response analysis with collaboration with key stakeholders, the team were able to:
• Identify the root cause of what was a major vibration issue.
• Develop a unique structural frame design that was successful in isolating from the overall structure, from the vibratory forces at their source.