Anderson Acoustics has provided noise and vibration services to various main contractors on the Crossrail project. We were involved in some of the most significant and challenging work packages, for both surface and underground works, including the construction of the Western Running Tunnels. Employed by BFK Joint Venture, we assessed, managed and monitored airborne and groundborne noise and vibration impacts of the construction works.
Aiming for first time consent from the local authority reduces the risk of delays to the process. We worked closely with the main contractors’ environment and construction teams to develop a thorough understanding of the various construction processes occurring in the sites across London. This enabled us to assess the impacts using robust predictions and assessments, developing effective best practicable means (BPM) in accordance with the requirements of the Crossrail Act.
Western Running Tunnels
The Western Running Tunnels are formed beneath one of the most densely populated areas of Europe, between West London and Farringdon. With thousands of noise sensitive properties above the tunnelling or close to one of the 20+ worksites, there is potential for the community or businesses to be affected at any point in the day. Managing noise and vibration is a huge undertaking and if not carried out correctly could lead to costly delays and penalties.
Innovative BPM which we developed included unique barrier solutions, alternative working practices and monitoring. At one particular site with residents in close proximity, we developed a real-time cost-effective solution that directly advises the site team when exceedances of agreed limits occur. The site team was trained to understand the cumulative impact of their construction activities. Using the information delivered directly to their phones, they are now able to adjust activities to minimise the risk and prevent exceedance from occurring.
Can you hear the TBM?
Local authority concern pointed at the impact of the Tunnel Boring Machines (TBMs) as they passed under West London. We obtained sound and vibration data in three locations over a two-month period as Phyllis (the TBM) bored through London clay twenty metres below ground. Reliable information on TBM noise and vibration impacts was not available at the time, and our monitoring and assessment was used to gain a better understanding of potential noise impacts later on in the process.
We found that in some cases the TBM could be audible at the surface, albeit at low sound levels. It was therefore hugely important to engage with those that could be affected before any disruption occurred. Our findings enabled BFK to undertake proactive communications, minimising potential disruption and avoiding any costly delays to the construction works.
Award winning technical excellence
Assessing groundborne noise and vibration impacts of the temporary construction railway required a leading-edge approach. Sophisticated modelling software was used to predict impacts at sensitive receptors including dwellings and studios. These results were then validated with a rigorous measurement programme (including in-tunnel). The credibility of our approach was recognised by our industry winning the 2013 Association of Noise Consultants Award in Environmental Acoustics.
A team that delivers
Throughout the project, we have helped obtain seventy consents and ensured that Crossrail requirements have been met, often under challenging timescales. A large-scale programme of compliance based attended and unattended monitoring is still underway. We have been able to deliver last-minute attended monitoring (often at night) in response to community complaints. By responding rapidly and ensuring preventative action could be taken if needed, we have been able to reduce the risk of disruption to the programme.
“Anderson Acoustics had to overcome a significant number of technical challenges. The work they undertook is, no doubt, industry leading.”
– Colin Cobbing, Lead Noise and Vibration Specialist, Crossrail Ltd