Traffic Flow and Calming Measures - Silence Training Workshop - Warsaw 2007

Training Workshop Warsaw, 14 November 2007

[email protected]

The role of traffic flow and traffic calming measures

Results of SILENCE WP H1

Lars Ellebjerg Danish Road Institute


2

Traffic volume - noise effect of reducing traffic volume

Reduction in traffic volume Reduction in noise (LAeq)

10 % 0.5 dB

20 % 1.0 dB

30 % 1.6 dB

40 % 2.2 dB

50 % 3.0 dB

75 % 6.0 dB

Source: H. Bendtsen et al., 2004


3

60

65

70

75

80

85

90

95

0 20 40 60 80 100 120 140 160 180

vehicle speed in km/h

avera

ge L

max in d

B(A

)

cars

LDV

public transport bus

HDV <= 3 axles

HDV > 3 axles

motorcycles

mopeds

Traffic composition - noise emissions from various vehicles

Source: H. Steven, 2005


4

Speed - noise effect of reducing speed

Reduction in speed (km/h)

Noise reduction (LAE, dB) - light vehicles

Noise reduction (LAE, dB) - heavy vehicles

130 to 120 1.0 -

120 to 110 1.1 -

110 to 100 1.2 -

100 to 90 1.3 1.0

90 to 80 1.5 1.1

80 to 70 1.7 1.2

70 to 60 1.9 1.4

60 to 50 2.3 1.7

50 to 40 2.8 2.1

40 to 30 3.6 2.7

Source: B. Andersen, 2003


5

45

50

55

60

65

70

75

80

0 20 40 60 80 100 120 140

vehicle speed in km/h

max.

pass b

y l

evel

in d

B(A

), p

rop

& r

oll

ing

no

ise

acceleration, gear 1





rolling noise

mid size car

Propulsion and rolling noise



6

Driving pattern - effect of accelerations vs. steady speed


Vehicle category At 30 km/h At 50 km/h

Car +2.0 +1.4

Light goods vehicle +3.5 +2.3

HGV, Pn< 75 kW +4.4 +3.5

HGV, 75 < Pn < 150 +4.4 +3.6

HGV, 150 < Pn < 250 +3.5 +3.0

HGV, Pn ≥ 250 kW +3.5 +2.7


7

Up to 4 dB LAeq reduction

Up to 7 dB LAmax reduction

Traffic calming

Highly dependent on:

• Traffic composition

• Speed

• Road layout

• Choice of measures


8

Narrow cushions

Heavy vehicles:

Up to 2 dB LAmax

increase

Wide cushions

Heavy vehicles:

Up to 10 dB LAeq and 8

dB LAmax increase

Humps and cushions

Flat-top humps

Heavy vehicles:

Up to 8 dB LAeq

increase

Round-top humps

Heavy vehicles:

Up to 8 dB LAeq

increase at speeds

higher than 25 km/h


9

If effect on trucks

No effect on cars

If effect on cars

Trucks cannot pass

Noise effect determined by speed effect

If road is narrowed to one lane, braking and accelerating vehicles may cause noise and annoyance

Chicanes


10

Mini-roundabouts

Need for further studies of:

• Effect on noise from heavy vehicles

• Influence of roundabout design

Speed reductions

Less braking and accelerating



11

Gateways

• Raise awareness rather than reduce speed

• Usually used in combination with other measures

• May support the speed reducing effect of other measures


12

Junctions

Types of junctions –Roundabouts, crossings

–Signalization, stop sign, right-of-way, priority to the right

Signalization –Green waves, “all red”, “main green”


13


Roundabouts - compared with other intersection layouts

Need for further studies of influence of roundabout design


14

Junction type and driving pattern

Tests of the effect of driving pattern in various types of junctions in SILENCE:

• Driving patterns: eco-driving, normal and aggressive

• Test with one driver in one passenger car

Results • No difference between various types of junctions!

• Eco-driving vs. normal driving: 5-600 rpm lower engine speed 3 dB(A) lower external noise

• Normal vs. aggressive driving: 1000 rpm lower engine speed 6 dB(A) lower external noise

• Maximum accelerations recorded: eco: 1 m/s2 normal: 2 m/s2

aggressive: 3 m/s2

Source: T. Berge, 2007


15

Calming green waves

Speed reduction: 15 km/h

LAeq reduction: 2.5 - 3 dB

Source: Ellenberg and Bedeaux, 1999


16

Reducing speed limit

with interactive signs

Speed reduction:

5-10 km/h (up to 20 km/h)

Noise reduction:

1-2 dB (up to 3 dB) LAeq

Reducing speed limit

With static signs

Speed reduction:

0-3 km/h

Noise reduction:

0 dB LAeq

(1-3 dB if enforced through

massive police control or

ATC)

Speed restrictions


17

Noise dependent speed restrictions in Gleisdorf

Source: Bendtsen et al., 2004


18

Results from

London and Stockholm:

0 dB LAeq

Traffic volumes decrease, but speed goes up!

Congestion charging


19

Bans on trucks and/or motorcycles

Effect on LAeq depends on the percentage of the

total traffic volume which is trucks/MCs

Night-time restrictions

Will reduce number

of noise peaks

during the night

Source: Griefahn, 1985


20

City logistics

Unlikely to significantly reduce the overall noise levels, but it may reduce the number of peaks

Reduced annoyance and/or sleep disturbance


21

Conclusions

Reducing traffic volume

–Effective on minor roads

–Difficult/”impossible” on major roads

Changing traffic composition

– Little effect on LAeq-levels

–May reduce peaks and thus annoyance and sleep disturbance


22

Conclusions 2

Speed reductions

–Humps and chicanes primarily on minor roads

– Interactive/variable signs

–Automatic traffic control and/or police enforcement


23

Conclusions 3

Driving pattern

–Roundabouts

–Calming green waves?


[email protected]

Thank you for your attention!


25

References

• Andersen, Bent, 2003. Støjudsendelse fra biler på vejnettet. Kgs. Lyngby: Danish

Transport Research Institute. Report 2. (English summary) Available from

http://www.trm.dk/graphics/Synkron-Library/DTF/PDF/Rapporter/rap0203.pdf.

• Bendtsen, Hans; Haberl, Jürgen; Litzka, Johan; Pucher, Ernst; Sandberg, Ulf and Watts,

Greg, 2004. Traffic management and noise reducing pavements – Recommendations on

additional noise reducing measures. Copenhagen: Danish Road Directorate. Report 137.

Available from http://www.vejdirektoratet.dk/publikationer/VIrap137/index.htm.

• Berge, Truls, 2007. Measurement of driving pattern in crossings and roundabouts.

Trondheim: SINTEF. Project no. 90E230.03.

• Ellebjerg, Lars, 2007. Effectiveness and Benefits of Traffic Flow Measures on Noise

Control. European Sixth FP SILENCE WP H1. Available from

http://www.silence-

ip.org/site/fileadmin/SP_H/SILENCE_H.D1_20070105_DRI_Final.pdf.

• Steven, Heinz, 2005. Investigations on Noise Emission of Motor Vehicles in Road

Traffic. Research Project 200 54 135, Final Report. Wuerselen: RWTUEV Fahrzeug

GmbH.

http://www.trm.dk/graphics/Synkron-Library/DTF/PDF/Rapporter/rap0203.pdf



http://www.vejdirektoratet.dk/publikationer/VIrap137/index.htm

http://www.silence-ip.org/site/fileadmin/SP_H/SILENCE_H.D1_20070105_DRI_Final.pdf



Traffic Flow and Calming Measures - Silence Training Workshop - Warsaw 2007

Documents

Transcript of Traffic Flow and Calming Measures - Silence Training Workshop - Warsaw 2007