The document discusses the design of a noise barrier. It describes experiments conducted to test noise barriers on hard ground. It discusses using the LAM method in MATLAB to model insertion loss and compare results to experimental data. It also discusses modeling barriers using OLT software and analyzing barriers by varying height, thickness, material, and panel configuration to evaluate insertion loss. The goal is to experimentally test different materials and barrier configurations and compare results to modeling.

1. Designing of Noise Barrier
Lalit Aggarwal P2009ME1088
Gayathri Lakshmi K. P2009ME1062

2. Problem description
• Aim
• Experimental
• Formulation in MATLAB
• Modeling using software
Designing of Noise Barrier 2

3. Index
• Experiment
• Formulation in MATLAB
– Comparison with experimental results
– MATLAB GUI
• Modeling using software OLT
– Comparison with experimental results
– Analysis using software
Designing of Noise Barrier 3

4. Experiment on hard ground
Designing of Noise Barrier 4

5. Designing of Noise Barrier 5

6. Insertion loss due to a semi-infinite
barrier
• LAM Method
– Diffraction based model
– Based on the path difference
– Summing the contribution of each path
– Applicable for hard ground, thin and semi-infinite
barrier.
Designing of Noise Barrier 6

7. Paths considered in LAM Method
Designing of Noise Barrier 7

8. MATLAB GUI
Designing of Noise Barrier 8

9. Comparison
Designing of Noise Barrier 9

10. Comparison
Designing of Noise Barrier 10

11. Height Variation
35
30
25
Insertion Loss(in dB)
20
1000 Hz
1259 Hz
1995 Hz
15
3162 Hz
3981 Hz
10
5
0
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5
Barrier height(in m)
Reference: Olive Lab Tree Terrain Designing of Noise Barrier 11

12. Required Thickness
• Mass Law
TL=20*log(m)+20*log(f/100)-7
m=surface density
f= frequency
Reference: http://rwsc2.inforce.dk/sw98684.asp
Designing of Noise Barrier 12

13. barrier thickness Material: Glasswool
0.12
Flow resistivity=20000
Pas/m2
0.1
0.08
barrier thickness(in m)
0.06
barrier thickness
0.04
0.02
0
0 500 1000 1500 2000 2500 3000 3500 4000 4500
Frequency(in Hz)
Designing of Noise Barrier 13

14. Thickness Variation Material: Glasswool
30
Flow resistivity=20000
Pas/m2
25
20
Insertion Loss(in dB)
15
thickness_3cm
thickness_3.5cm
thickness_4cm
10
thickness_4.5cm
5
0
0 10 20 30 40 50 60
-5
Receiver distance (in m)
Reference: Olive Lab Tree Terrain Designing of Noise Barrier 14

15. Single panel barrier Double panel barrier
Reference: Olive Lab Tree Terrain Designing of Noise Barrier 15

16. Insertion Loss variation in double panel barriers
45
40
Frequency = 1000 Hz
35
30
25 single panel
double panel_gap10cm
Insertion Loss(in dB)
double panel_gap20cm
20
double panel_gap 30cm
double panel_gap50cm
15
double panel gap 40 cm
10
5
0
0 2 4 6 8 10 12
Receiver distance(in m)
Reference: Olive Lab Tree Terrain Designing of Noise Barrier 16

17. Insertion Loss variation in double panel barriers
45
40
Frequency = 2000 Hz
35
30
Insertion Loss(in dB)
25 single panel
double panel_gap10cm
double panel gap 20 cm
20
double panel_gap 30cm
double panel_gap 40 cm
15
double panel_gap50cm
10
5
0
0 2 4 6 8 10 12
Receiver distance (in m)
Reference: Olive Lab Tree Terrain Designing of Noise Barrier 17

18. Variation in flow-resistivity
35
30
25
20
IL(in dB)
2.54 cm glasswool (20000)
2.54 cm glasswool (50000)
15 5.1 cm glasswool(20,000)
gypsum_4,200,000
10
5
0
0 2 4 6 8 10 12
distance from barrier(in m)
Reference: Olive Lab Tree Terrain Designing of Noise Barrier 18

19. Future Work
• Experimental Results of Material Selection and
double panel and comparison
• Sysnoise design includes shape variation
• Matlab for thick barrier
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20. References
Research Papers
• A. Muradali and K. R. Fyfe, A Study of 2D and 3D Barrier Insertion Loss
using Improved Diffraction-based Methods, Applied Acoustics, Vol.
53, No. I-3, pp. 49-15, 1998
• Maekawa, Z., Noise reduction by screens. Applied Acoustics, 1968, 1, 157-
173.
• D. C. HOTHERSALL, S. N. CHANDLER-WILDE AND M. N.
HAJMIRZAE, EFFICIENCY OF SINGLE NOISE BARRIERS, Journal of Sound
and Vibration (1991) 146(2), 303-322
Others:
• Report on DESIGN THE NOISE BARRIER FOR THE BAFFLE RANGE by Sahil
Bhagat.
• http://en.wikipedia.org/wiki/Noise_barrier
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