J. Environ. Res. Develop. Journal of Environmental Research And Development Vol. 7 No. 4A, April-June 2013

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1 DESIGN OF A NOISE BARRIER FOR BRITANNIA CHOWK FLYOVER IN DELHI, INDIA Randhawa Rominder* 1, Parida M., Jain S.S. 2 and Moin Khalid 3 1. Guru Tegh Bahadur Institute of Technology, New Delhi (INDIA) 2. Department of Civil, Indian Institute of Technology, Roorkee (INDIA) 3. Faculty of Engineering, Jamia Millia Islamia, New Delhi (INDIA) Received December 05, 2012 Accepted April 05, 2013 ABSTRACT Traffic noise is associated with numerous health problems for habitation exposed to high density of traffic operation. Expansion of urban traffic infrastructure has resulted in significant noise pollution. Noise barriers are common mitigation strategy to contain traffic noise. A methodology for noise barrier design has been presented for traffic noise reduction in Delhi. This idea has been implemented by Public Works Department (PWD), Delhi, India for the busy Britannia chowk flyover. Data has been collected for 24 hours duration regarding traffic volume, traffic speed, road geometrics and ambient noise level for this intersection. In the above project Noise Barrier was designed adopting three approaches, i.e., Acoustical design, Structural design and Aesthetic design. On the basis of comparison, a final design had been suggested. After the erection of the barrier, it was observed that the barrier proved very effective for reducing traffic noise. People in the vicinity also expressed satisfaction with the implementation of noise barrier. Key Words : Noise barrier, Flyover, Barrier effectiveness, Traffic noise, Public Works Department (PWD) INTRODUCTION Traffic noise has been reported as a major nuisance in many countries of the world. Noise levels are increasing continuously and exceed the prescribed levels in almost all forms of land use zones namely residential, commercial, heavy traffic and even in the silence zones. Among these, operational noise from transportation system alone contributes to about 70% of total environmental noise. Traffic noise is associated with numerous health problems such as temporary or permanent threshold shift of hearing mechanism, loss of hearing, psychological strain, mental fatigue, annoyance, headache, hypertension, damage to heart and various other physic biological disturbances like changes in digestion metabolism, blood circulation. Noise level above 130 db (A) can even cause death. Duly engineered noise barriers alongside *Author for correspondence highways are effective in reducing noise level to prescribed standards. There are many successful projects of noise barrier both outside and inside India. A few studies are discussed below where noise barrier design aspect has been addressed by researchers. A novel method to design a noise barrier using the global optimization of a Simulated Annealing (SA) algorithm was proposed by Mun and Cho. 1 This method focuses on minimizing barrier dimensions. Investigations were carried out to study the shadowing effect of barriers of infinite or finite length in the presence of directional noise sources by Menounou and Papaefthymiou. 2 A new formula that incorporates effects of diffraction theory and reflection of sound between room surfaces was proposed by Lau and Tang. 3 Study involved experimental, theoretical and numerical analyses of the insertion loss provided by rigid noise barriers in an 1644

2 enclosed space. A systematic approach to determine reasonable heights and locations for noise barriers adjacent to railway lines was presented by Weber and Atkinson. 4 Considering finite length of traffic flow, an optimized design method of noise barrier used in reducing noise emission from traffic vehicles was presented by Xintan and Shuiliang. 5 Cost of noise barrier was chosen as objective function. Shukla, measured noise levels on the flyover in front of Institute of Engineering and Technology (IET Lucknow, Uttar Pradesh, India) and designed a noise barrier for this location. 6,7 AIMS AND OBJECTIVES To study the noise levels at a busy intersection, Britannia chowk flyover and design of a noise barrier for this flyover and analysis of reduction in traffic noise levels. MATERIAL AND METHODS Britannia chowk is a congested four-legged intersection with mixed kind of land use, both industrial and residential. Geometric data collected from site and its layout with the flyover 7 is presented in Fig 1. A detailed field data collection program was designed 8,9 to collect data of traffic volume, traffic speed, and ambient noise level. The vehicle categories were car/jeep/van, mini bus, bus, two-wheeler mini-truck, truck, tractor/trailer, 3-wheeler, cycle and rickshaw. Classified traffic volume data was collected manually for duration of 24 hours in both the directions at Britannia chowk flyover. The intersection is characterized by mixed traffic conditions resulting in complex interaction between various kinds of vehicles. The capacity of road was expressed in terms of a common unit PCU. Each vehicle type is converted into equivalent PCUs based on their relative interference value. Classified traffic volume data has been collected for duration of 24 hours for both the directions for different vehicle types and given in Table 1. Ambient noise levels due to traffic flow are observed continuously for duration of 24 hours for both the directions. The observed noise level at Britannia Chowk flyover is given in Table 2 shows the hourly variation of observed noise level for both the directions. Note: All Dimensions are in metres Fig. 1 : Cross section of Britannia chowk flyover 1645

3 Table 1 : Summary of traffic volume in terms of number and PCU values Vehicle category Direction 1 Volume (vph) Direction 2 Total Number PCU Number PCU Number PCU Car/Jeep/Van Mini Bus Bus Wheeler Mini Truck Truck Tractor/ Trailor Wheeler Cycle Rickshaw Total vehicles Total PCU Table 2 : Observed Leq values at Britannia chowk Time (Hrs.) Noise level (Leq) Wazirpur to Punjabi bagh Punjabi bagh to Wazirpur 7:00-8:00 AM :00-9: :00-10: :00-11: :00-12: :00-1:00 PM :00-2: :00-3: :00-4: :00-5: :00-6: :00-7: :00-8: :00-9: :00-10: :00-11: :00-12:00 AM :00-1: :00-2: :00-3: :00-4: :00-5: :00-6: :00-7: :00-8:

4 Design of noise barrier Noise barrier was designed from (i) Acoustical (ii) Structural and Aesthetic considerations. Modified FHWA model (1) was used to estimate height of the barrier. Instead of using any expensive imported material, effort was made to identify suitable material from local market. Proper design of noise barrier system requires the consideration of variety of structurally related factors like flexural strength, tensile strength etc. Glass fiber Sheet thickness (mm) reinforced plastic material was tested for quality assurance and assessment of properties to its suitability for application. The following tests were conducted on plastic material for different thickness at Institute Instrumentation Centre, IIT Roorkee, India. The summary of test results for 5mm, 6mm and 8mm are shown in Table 3 reduction of noise level for different thickness with respect to design height of noise wall i.e. 2.67m are shown in Table 4. Table 3 : Summary of density, flexural strength and tensile strength Flexural stress (N/mm 2 ) Tensile stress (N/mm 2 ) Density (gm/cm 3 ) 5 mm mm mm Table 4 : Variation of noise level with barrier thickness and height Sheet thickness (mm) Height of barrier (m) Noise level db(a) 5 mm mm mm Load calculations and sectional details of noise barrier Wind pressure in Delhi region = 150 kg/m 2 Maximum bending moment due to wind load = 150 x 1.67 x 1 x 1.67 x ½ = 210 kg -m Total moment = 210 kg -m Total horizontal force, ph = 150 x 1.67 = 250 kg Check for spacing between two angles M/Z =f M = 210 kg -m Z = I/y = Lt 2 /6 = L x /6 F perm = 107 N /mm x 10 6 kg/m 2 210/(L x /6) = 10.7 x 10 6 L = 3.27 m Hence, a spacing of 1.0m between two angle sections. Design of steel angles Steel angles are chosen to hold the plastic sheet M/z = bc or bt bc or bt bc or bt Where, f y = bending stress (compressive or tensile) at a point at a distance of y from neutral axis = 0.66 f y = yield stress of steel = 2500 kg/cm 2 bc or bt = 0.66 x 2500 = 1650 kg/cm / z required = 1650 z required = / 1650 = cm 3 Choosing from steel tables ISA 80 x80 x 10 mm having Z xx = 15.5 cm 3 Weight of angles = 11.8 x 1.67= 19.7kg Vertical force, P v = 2x = 55.4kg Considering all other gravity forces, Total vertical force acting on noise barrier = 200 kg 1647

Summary of loading calculations are shown in Table 5. Structural design task was completed to develop a barrier structure which confirms with safety norms and practices.

5 Summary of loading calculations are shown in Table 5. Structural design task was completed to develop a barrier structure which confirms with safety norms and practices. Table 5 : Load on crash barrier (per metre width of barrier) S/N Force/Moment Quantity 1 Bending moment 210 Kg -m 2 Horizontal force 250 Kg 3 Vertical force 200 Kg Placement details of noise barrier over flyover are shown in Fig. 2. Noise barrier colour and pattern was decided by use of visualization software. The adopted design is given in Fig. 3 Fig. 2 : Cross section of noise barrier RESULTS AND DISCUSSION The design suggested for noise barrier was implemented at Britannia chowk flyover. After construction of noise barrier its effectiveness was also studied. From the studies Fig. 3 : Connection details of noise barrier 1648 carried out at Britannia chowk flyover for entire three phases the analysed results for noise studies are presented below in Table 6 showing the comparison of noise levels for each phase of study during day and night

6 time respectively. The noise barrier has been effective in reducing noise level to acceptable standard both in day time and night time. Table 6 : Summarised noise levels during three phases at Britannia chowk Time Stage 1 (Before construction) Punjabi bagh to Azadpur Stage 2 (During construction) Noise Level db(a) Punjabi bagh to Azadpur Stage 3 (After construction) On ground On flyover 6.00 AM PM PM-6.00 AM The barrier has significantly reduced the noise levels of the flyover traffic to the nearby residential and commercial localities as was evidently clear from the response of the general public (shopkeepers, hawkers, residents, and children) who were interviewed in the survey. The children found the new ambience less disturbing and helpful to their studies. The ladies found the new ambience less dusty and less smoky. In general, the public found the execution of the barrier Project a welcome change to a better environment. Table 7 shows reduction in noise level at Britannia chowk flyover with noise barrier. Table 7 : Study on effectiveness of noise barrier at Britannia chowk Time Noise level On ground On flyover Difference PM AM

CONCLUSION From the field studies of traffic noise, it was observed that noise level exceeded prescribed standard at Britannia chowk flyover and was significantly higher than the standards for

7 CONCLUSION From the field studies of traffic noise, it was observed that noise level exceeded prescribed standard at Britannia chowk flyover and was significantly higher than the standards for different land use zones prescribed by Central Pollution Control Board (CPCB), New Delhi, India. To reduce noise level in the adjoining residential areas noise barrier was designed over the crash barrier of the flyover. The recommendations has been implemented at the site by Delhi PWD. Glass Fibre Reinforced Plastic Sheet (locally available in Delhi) was recommended for construction of the barrier.noise level measurement carried after the barrier was constructed indicated the effectiveness of barrier in reducing noise significantly.residents were interviewed to ascertain their respons towards the barrier project.they provided positive feedback strengthening development of noise barrier as an effective environmental mitigation strategy. REFERENCES 1. Mun S. and Cho YH, Noise barrier optimization using a simulated annealing algorithm, Appl. Acoust., 70(8), , (2009). 2. Menounou P. and Papaefthymiou ES, Shadowing of directional noise sources by finite noise barriers, Appl. Acoust. 71(4), , (2010). 3. Lau S.K. and Tang S.K., Performance of a noise barrier within an enclosed space, Appl. Acoust., 70(1), 50 57, (2009). 4. Weber C. and Atkinson K., A systematic approach for arriving at reasonable heights and locations for noise barriers adjacent to railway lines, Noise and vibration mitigation, Not. Num. Fluid Mech., NFM, 99(1), , (2008). 5. Xintan M. and Shuiliang L., Optimization of road noise barrier based on finite length of traffic flow. IEEE doi: /ICEICE , (2011). 6. Shukla A.K., An approach for design of noise barriers on flyovers in urban areas in India. Int. J. Traf. Transport Eng., 1(3), , (2011). 7. Kumar Amar Venkata, Noise Impact Assessment Due to Flyovers in Delhi, M.E. Dissert., Department of Civil Engineering, I.I.T. Roorkee.(2003). 8. Jain S. S. and Parida M., final report on study of transport related noise pollution (Delhi, Jaipur, Allahabad, Chandigarh & Lucknow cities of India) for Urban Transport Environment Interaction Under Nationally Coordinated Project, Submitted to AICTE, New Delhi.(2004). 9. Parikh Saloni and Shukul Maneesha, Adverse effect of noise on homemakers of selected area in Vadodara, India, J. Environ. Res. Develop., 7(2), , (2012). This fight against drilling in the Arctic Refuge is a fight about our principles. It's about standing up for our environment, our families and our future, and I won't give up this fight. Senator John Kerry 1650

ROAD TRAFFIC NOISE MAPPING AND A CASE STUDY FOR DELHI REGION

ROAD TRAFFIC NOISE MAPPING AND A CASE STUDY FOR DELHI REGION *Nasim Akhtar 1, Kafeel Ahmad 2 and S. Gangopadhyay 3 1 Transport Planning Division, CSIR-Central Road Research Institute, New Delhi 110025,