Thanks Jan for this info
- Dr John Heilig: Vibration & regenerated noise from construction
Must accept that there will be challenges but firmly believes they can be managed with appropriate EPRs and the CNVMP (Construction Noise & Vibration Management Plan). Domain buildings recognised as stakeholders with signif vibration & ground-borne noise impact. Believes that infrastructure integrity & personal amenity can be managed & protected. Emphasised that vibration standards worldwide are moving away from specific numeric triggers to managing vibration. Long involved description of British vs Ger standards! Has had a lot of relevant experience. Quite impressive.
- Nick Tweedie for IAC focussed on the need for dilapidation surveys & determining which buildings would be deemed eligible. Expert pointed out that there are 2 options: distance from the work activity OR assessment of potential vibration/predicted trigger lvl. Agreement that the 2nd option, identifying potentially affected buildings, would be preferable. EPR to be modified to include that buildings which would potentially reach a trigger lvl must have dilapidation/condition report carried out.
Tweedie also made the point that in the RIMG Sect 3.2 Ground-borne noise & vibration, there are no mitigation measures for daytime ground-borne noise exceedence. Discussion re the likely impact of the TBM which would be well above ambient daytime noise levels. Expert agreed that daytime mitigation measures should be included when trigger lvl is reached
- Paul Chiappi pointed out that, in terms of Human Comfort, (Technical Appendix I, Appendix B), Botanica’s daytime vibration levels are identified as being more than 2 times the maximum guideline target and ground-borne noise levels more than 10dB(A) above the night guideline target. He stressed that resident impact is determined by both level & duration of exceedence. Expert didn’t know how long high levels of vibration would be expected to last. Expert agreed that, as recommended by Neville Goddard, mitigation measures to reduce vibration impact should be included in the CNVMP eg. scheduling rock-breaking works for normal working hours only, adjusting buffer zones, use of low-vibration methods of rock-breaking close to residential receivers.
One thought on “Metro Tunnel – Vibration”
Thank you Jan and Gary, I truly appreciate the time you are giving to follow up , investigate and attend meetings and hearings , putting all the residents of The Botanica in the best position to protect our lives before during and after construction. Sandy