Dubai Municipality LRT Noise and Vibration Impact Stage 2 Environmental Impact 11 th of April, 2004
Environmental Impact Report According to the PS007 Agreement, Environmental Impact Report Based on Noise and Vibration generated by the train in operation Future Contractor In charge of other Aspects of Environmental Impact Study
Environmental Impact Report According to the PS007 Agreement, Environmental Impact Report Based on Noise and Vibration generated by the train in operation Future Contractor In charge of other Aspects of Environmental Impact Study
NOISE / VIBRATION CONSULTING
PLAN I - II - III - Introduction : acoustics and Vibrations Principles International Regulations Proposal for Noise and Vibration Limits IV - Noise and Vibrations Computation, Deliverables
I - ACOUSTICS & VIBRATIONS PRINCIPLES I - I acoustics A noise source is characterized by its Acoustic Power in Watts and its Directivity Lw = 10 log (W/W0) in decibels W0 = 10-12 Watts Sound Pressure Level (SPL) Lp = Lw + 10 log (Q/S) in decibels. SPL decrease in free field : point source : 6 decibels per distance doubling. Line source : 3 db per distance doubling.
I - ACOUSTICS & VIBRATIONS PRINCIPLES I - I acoustics A weighting Typical SPL at 25m from LRT : 77 db(a) at 25 m and 80 km/h in free field.
I - ACOUSTICS & VIBRATIONS PRINCIPLES I - I acoustics Période 6h-22h Période 22h-6h Source Leq Leq Lmin Lmax L90 L50 Durée particulier (partiel) cumulée [db(a)] [db(a)] [db(a)] [db(a)] [db(a)] [db(a)] h:min:s Trains 85.3 71.2 45.3 96.8 51.5 59.7 00:37:30 Résiduel 53.5 53.3 42.8 80.3 47.4 51.5 15:22:30 Global 71.3 71.3 42.8 96.8 47.5 51.6 16:00:00 Source Leq Leq Lmin Lmax L90 L50 Durée particulier (partiel) cumulée [db(a)] [db(a)] [db(a)] [db(a)] [db(a)] [db(a)] h:min:s Trains 86.5 72.5 43.9 95.2 48.6 60.5 00:19:10 Résiduel 47.5 47.3 40.7 64 44.1 45.9 07:40:50 Global 72.6 72.6 40.7 95.2 44.2 46 08:00:00 Level Equivalent 100 Evolution du L Aeq sur 24 heures 90 Trains Résiduel 80 LAeq [db(a)] 70 60 50 40 19:00 19:44 20:28 21:13 21:57 22:41 23:26 00:10 00:54 01:39 02:23 03:07 03:52 04:36 05:20 06:05 Temps [h:min] 06:49 07:33 08:18 09:02 09:46 10:31 11:15 11:59 12:44 13:28 14:12 14:57 15:41 16:25 17:10 17:54 18:38
I - ACOUSTICS & VIBRATIONS PRINCIPLES I - 2 vibrations
I - ACOUSTICS & VIBRATIONS PRINCIPLES I - 2 vibrations 0 Ground Attenuation (geometry + dissipation) -5 Atténuation (décibels) -10-15 -20 Dispersion cylindrique Dissipation Att. Totale [cylindrique] Dispersion de Rayleigh Att. Totale [Rayleigh] -25 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Distance (mètres)
I - ACOUSTICS & VIBRATIONS PRINCIPLES I - 2 vibrations Finite elements model : - Track - Ground - damping
INTERNATIONAL REGULATIONS DUBAI local order 61/91 Europe Directive june 25th 2002 USA Federal Transit Administration
INTERNATIONAL REGULATIONS Large Projects : (LRT, High Speed) TWO DIFFERENT SET OF CRITERIA DEPENDING ON TYPE OF PROJECT Predicted project noise level alone must comply with a noise criteria Noise criteria depend on land use Example : LAeq day < 65 db(a) Limited Area project : Comparison of overall cumulative noise with / without project Example : noise level chang (day) < 5 db(a)
INTERNATIONAL REGULATIONS DUBAI LOCAL ORDER : Maximum noise level change : Day : 07h00 20h00 : Background + 5 db(a) Night : 20h00-07h00 : Background + 2 db(a)
INTERNATIONAL REGULATIONS EUROPE Directive june 25th 2002 (applicable july 2004) : Lden (day evening night) (annoyance) and Lnight (sleep annoyance) (7h-19h, 19h-23h, 23h-7h) Lden = 10 log 1/24 (12*10^Lday/10 + 4*10^Leve+5/10 + 8*10^Lnight+10/10 ) Lden and Lnight limit values are specified by State members.
INTERNATIONAL REGULATIONS Indicators and limits in Europe today (new railway lines alone) : Germany Leq(6h-22h)<67 db(a), Leq (22h-6h)<57 db(a) Netherlands Lday < 60 db(a), Lnight < 50 db(a) Italy Leq(6h-22h)<65 db(a), Leq(22h-6h)<55 db(a) France Leq(6h-22h)<65 db(a), Leq (22h-6h)<60 db(a) (TGV -5 db) Switzerland Leq(6h-22h)<68 db(a), Leq (22h-6h)<58 db(a) Osterreich Leq(6h-22h)<68 db(a), Leq (22h-6h)<58 db(a) (simplified) Railway lines renewal (France) : Max level change : + 2 db(a)
INTERNATIONAL REGULATIONS USA : Federal Transit Administration FTA (see Impact assessment Guidance Manual 1995) Rail transit Predicted project noise level alone must comply with a noise criteria Noise criteria depend on land use Road local transit : Comparison of overall cumulative noise with / without project
INTERNATIONAL REGULATIONS VIBRATIONS No regulation today, only recommendations ISO 2631/2 (1989) Appendix A : - tactile perception : 0.1 mm/s rms (8-80 Hz) -Residential : 0.14 to 2 mm/s rms, -Offices : 0.4 mm/s rms
NOISE and VIBRATION LEVELS PREDICTION Noise maps using ray-tracing techniques
NOISE and VIBRATION LEVELS PREDICTION Noise maps using ray-tracing techniques
NOISE and VIBRATION LEVELS PREDICTION Noise maps using ray-tracing techniques N > 70 65-70 60-65 55-60 50-55 45-50 40-45 < 40 R1 R2 R4 R3 R5 R6 R7 R8 R9 R10 R13 R11 R14 R12 R15 R16 0 250m
NOISE and VIBRATION LEVELS PREDICTION Railway contribution (6h-22h) : noise level change LAeq futur (6h-22h) LAeq initial (6h-22h) Delta LAeq (6h-22h) 1 rdc 62.2 61.6 62.9 62.3 0.7 0.7 1 64.1 65.0 0.9 rdc 62.8 63.7 0.9 1 rdc 63.1 61.9 63.8 62.5 0.7 0.6 1 rdc 65.3 63.6 66.1 64.3 0.8 0.7 1 rdc 63.3 62.3 64.0 62.8 0.7 0.5 1 rdc 60.1 55.4 63.4 58.8 3.3 3.4 1 rdc 1 rdc R1 R2R4 R3 62.0 62.8 0.8 61.9 62.7 0.8 63.9 61.9 64.6 62.6 0.7 0.7 1 63.7 64.3 0.6 rdc 62.5 63.2 0.7 1 63.7 64.4 rdc 62.7 63.4 0.7 0.7 R5 R6 R7 1 rdc R8 63.9 62.2 R9 64.3 62.3 1 rdc R10 0.4 0.1 57.4 60.2 54.0 56.8 2 61.3 1 58.8 rdc 56.2 1 60.7 63.8 3.1 rdc 57.0 60.7 3.7 R11 R12 R13 R15 R14 R16 1 57.6 61.0 3.4 2.8 rdc 53.5 57.0 3.5 2.8 1 53.0 55.7 2.7 rdc 50.6 53.5 2.9 64.5 3.2 62.0 3.2 59.2 3.0
NOISE and VIBRATION LEVELS PREDICTION Finite Element Computing
NOISE and VIBRATION LEVELS PREDICTION Finite Element Computing 10 norme iso2631-a (bureaux) 15 km/h 20 km/h 25 km/h 30 km/h 35 km/h Vitesse vibratoire [mm/s efficace] 1 0.1 0.01 1 1.25 1.6 2 2.5 3.15 4 5 6.3 8 10 12.5 16 20 25 31.5 40 50 Fréquence [Hz]
NOISE and VIBRATION LEVELS PREDICTION DELIVERABLES PREDICTION, MITIGATION SOLUTIONS / NOISE : NOISE BARRIERS on track side, BALLAST on track slabs, WINDOWS with High Insertion Loss RESILIENT PADS under sleepers (reduces viaduct noise and structure borne noise) VEHICLE SKIRTS, undercar absorption
NOISE and VIBRATION LEVELS PREDICTION DELIVERABLES PREDICTION, MITIGATION SOLUTIONS / VIBRATIONS : RESILIENT PADS under sleepers, RESILIENT MATERIALS under buildings (heavy solution) GRINDING of rails and wheels WELDED RAILS
Red Line North Location of Long Term Point (24hours)
Rashid Hospital & Sheikh Zayed Road Location of Long Term Point (24hours)
Rashid Hospital Area Location of Long Term Point (24hours)
SAFA PARK AREA Location of Long Term Point (24hours)
شکرا Merci