Transport / Tunnel Infrastructure

The development of road infrastructure has the potential to alter the existing acoustic environment and therefore requires acoustic assessment. PKA have been involved in a number of projects for new road and tunnel developments.

New road developments typically require a 3D noise model to be constructed (using proprietary software such as SoundPlan). The modelling must take into account the regrading of existing topography, the predicted traffic flows, and the interface to existing residential and commercial areas.

The modelling procedure normally involves standardised calculation methodologies such as Calculation of Road Traffic Noise (CORTN) or Federal Highway Administration (FHWA).

The development of major infrastructure often also requires assessment and prediction of noise impacts during the construction phase. PKA can provide the necessary required Construction Noise Management Plan (CNMP) and mitigation strategies.

PKA have substantial experience in acoustic design and coordination for large mechanical plant items for road traffic tunnels, culminating in detailed acoustic design and specification for all mechanical plant associated with Australia’s largest road infrastructure project, the Brisbane Airport Link and Northern Busway.

Transport infrastructure tunnels can be many kilometres in length and are normally mechanically ventilated for their entire length. This requires the use of very large axial fans to supply and exhaust air from the tunnels. These fans are typically enclosed within ventilation station buildings, together with intake and discharge outlets

Jet fans are normally used to circulate air within the tunnels. There are normally strict acoustic design goals set by the project deeds, limiting noise from both the ventilation stations and the tunnel portals. The goals typically apply to:


  • Ventilation station outlet
  • Ventilation station inlet noise goals to tunnel and to portals
  • Ventilation supply station inlets (where applicable)


Other acoustic design requirements include:

Jet Fans

Acoustic specifications and spacing jet fans to meet tunnel and portal noise goals

Ancillary plant

Noise Control for emergency ventilation plant for cross passages, egress passages, pump stations.

Noise control for substations and associated ventilation plant.

PKA has specific project experience in the acoustic design and coordination necessary in ensuring that these goals are met. These projects include:


  • M5 East Tunnel Project (2000-2002) for Haden Engineering and Alsthom Australia
  • Lane Cove Tunnel Project (2004-2007) for Alsthom Australia / UGL Limited
  • Brisbane Airport Link and Northern Busway Project (2009-2012) for UGL Limited / TJH Joint Venture
  • Graham Farmer Freeway (Perth) Tunnel Upgrade Project (2013-2014) for UGL Limited


The above list is just a selection of the projects we have done. It is to show a cross-section of the solutions we can achieve for your project. But each job is different, and we engineer a solution to fit. So please don’t hesitate to contact us if you have a situation which is not listed here. Call PKA on 02 9460 6824 or Send an email to