Marshall Day Acoustics – Structural dynamics, rail vibration and building structural isolation

Marshall Day is recognised as a leader in vibration assessment and isolation. Our extensive reference list includes projects throughout Australasia and the Middle East.

The assessment of building vibration is complex, requiring considerable experience based on many years of successful projects. The analysis of rail vibration, its propagation through the ground, into buildings assessment and control using specialist or proprietary isolation materials requires a clear understanding of the nature of vibration and the principles involved.

FEDERATION SQUARE, Melbourne

Vibration Projects

	FEDERATION SQUARE, Melbourne, Australia: Marshall Day Acoustics is a leader in rail vibration assessment and isolation. Our extensive reference list includes projects across Australasia, from the Federation Square development in Melbourne (pictured) to the new KL Sentral Station project in Kuala Lumpur.
	BELL TOWER, Bendigo, Australia: In an unusual study the effect of a set of bells on the vibration of a church tower was analysed. The aim was to determine the frequency response of the bell support structure and the resulting vibration levels on the 100 year old church tower.The church was the Sacred Heart Cathedral in Bendigo, with a magnificent 97m high spire. At the 50m level a new bell peal was installed, with a requirement that it generated vibration levels within acceptable levels for historic buildings, and with a system natural frequency greater than 10Hz in the vertical mode and 5Hz in the lateral vibration mode.Marshall Day Acoustics conducted a finite element analysis study using the MSC Nastraan program and determined the natural frequencies of the system, which was reviewed to ensure compliance with the specification requirements.A site measurement at a similar installation in suburban Melbourne enabled the expected vibration response of a typical bell set to be determined. The information resulting from this survey was used to predict the expected vibration response of the proposed bell assembly at the Sacred Heart Cathedral.The vibration levels from the new assembly are expected to be sufficiently small to ensure that no structural damage will occur to the magnificent spire of the cathedral.