Many current problems are related to noise, which in many cases may be undesirable factorfor the daily activities and work conditions. This is especially evident in urban areas, where isa rapid growth of traffic including the number of vehicles, especially in peak time.Orientations and knowledge bases for the noise will take an important place in this paper,with the right understanding of this phenomenon.Till now in our country that is not taken into account in road and urban analyses. In this paperwe will orient the potential impact of noise in the administrative building in Pristina with P+30 floors, which is very close to the roundabout as a major source of noise. Such an outputdata, based on present measurements of the number of vehicles, made in a different specifiedperiod of time according to standards, and those elements will be interlinked with othergeometric and material parameters. All the analyses will show a result of the intensity of thenoise in dB. To analyze these parameters, intensity of the noise will be taken as the workloadof analyzed building. Also the result of unwanted intensity will be the factor for the designeddimensions and the calculation of the sound barriers in the roundabout, taking into accountthe incorporation in the environment and the urban planning of that part.The result will be presented as a 3D animation for this urban part and the impact of noise asan important factor, since we are dealing with a large concentration of administration in thisbuilding

A. Qorri

B. Ibrahimi

E. Beqiraj

N. Kabashi

V. Rexhepi

Epoka University

International Students’ Conference of Civil Engineering, ISCCE 2012, 10-11 May 2012, Epoka University, Tirana, AlbaniaTraffic noise in urban and regional roads and impact on the administrativefacility P+30 in PrishtinaA.Qorri1, B.Ibrahimi1, V.Rexhepi1, E.Beqiraj1, N.Kabashi11Faculty of Civil Engineering, University of Prishtina, Republic of KosovaABSTRACTMany current problems are related to noise, which in many cases may be undesirable factorfor the daily activities and work conditions. This is especially evident in urban areas, where isa rapid growth of traffic including the number of vehicles, especially in peak time.Orientations and knowledge bases for the noise will take an important place in this paper,with the right understanding of this phenomenon.Till now in our country that is not taken into account in road and urban analyses. In this paperwe will orient the potential impact of noise in the administrative building in Pristina with P+30 floors, which is very close to the roundabout as a major source of noise. Such an outputdata, based on present measurements of the number of vehicles, made in a different specifiedperiod of time according to standards, and those elements will be interlinked with othergeometric and material parameters. All the analyses will show a result of the intensity of thenoise in dB. To analyze these parameters, intensity of the noise will be taken as the workloadof analyzed building. Also the result of unwanted intensity will be the factor for the designeddimensions and the calculation of the sound barriers in the roundabout, taking into accountthe incorporation in the environment and the urban planning of that part.The result will be presented as a 3D animation for this urban part and the impact of noise asan important factor, since we are dealing with a large concentration of administration in thisbuilding.INTRODUCTIONIt is important to have some understanding of the nature of sound, because every noise is atype of sound. Noise is usually defined as unwanted sound. Thus it can present withvariations in magnitude that may be temporal or spatial in nature or a combination of both. Aparticular type of noise is known as environmental noise which is noise that is generated by avariety of outdoor sources and then propagates from outdoors to receivers that may besituated either indoors or outdoors. In turn, road traffic noise is one type of environmentalnoise.Noise is a serious issue that should be considered in all stages of transportation systemprojects, from original design and construction to modifications. Transportation-related noiseaffects millions of people and, in many cases, requires local, state, and federal governments toprovide noise abatement to help improve or restore their quality of life.International Students’ Conference of Civil Engineering, ISCCE 2012, 10-11 May 2012, Epoka University, Tirana, AlbaniaThere are many textbooks available which provide detailed treatments of the nature andphysics of sound, but some of the key features of relevance to the present abstract aresummarized below.• Sound is an elastic wave disturbance.• It occurs in any medium that has the properties of both mass and stiffness.• The most common medium in which environmental sound (noise) occurs is air, where ittravels as pressure fluctuations above and below atmospheric pressure.• The magnitude of these pressure fluctuations is termed the "Sound Pressure." It isgenerally measured in micro Pascals (Pa).• Sound pressures of typical sounds might range from 20 Pa to around 200,000,000 Pa.In the other hand we will concentrate a little in the designing of noise barriers, which is anexterior structure designed to protect sensitive land uses from noise pollution. Noise barriersare the most effective method of mitigating roadway, railway, and industrial noise sources –other than cessation of the source activity or use of source controls.At the end we have taken a “case study”, in which we have taken an example and made astudy of the traffic noise, where source is a very dense Roundabout, impacting anAdministrative and Trade Center in Prishtina about 10-15 meters close.1. SOUNDSound is a vibratory disturbance created bya moving or vibrating source. Examples oftransportation sound sources include steadytraffic on a highway, construction equipmentused to build a highway or bridge, and a jetflying overhead. Each sound source can bedescribed by its associated spectrum,amplitude, and time history.The amplitude of a sound indicates itsvolume; in general, higher amplitudesindicate louder sounds. The amplitude of asound can be measured as a sound pressurelevel with a microphone/sound level meter or spectrum analyzer system. Time-averagedsound levels or maximum sound levels are metrics often used to quantify sound, theassociated quantities presented in units of decibels (dB). A decibel level is a logarithmicrepresentation of sound energy and is calculated using a medium-dependent (e.g., air orwater) reference energy level. Sound reference level changes are presented in the table.1.1 NoiseCertain sounds are considered to be pleasant and therefore found to be acceptable to alistener; some sounds, on the other hand, are unwanted and therefore considered to be noise.Noise is defined in different ways, depending on the listener.It is straightforward to measure sound pressure levels in order to quantify sound; however,describing noise involves quantifying its perception. To describe sound levels in a mannerthat closely approximates normal human hearing, the actual sound levels are typicallymodified by applying A weighting. This is a response function that spans the audibleSound levelchangeDescriptive change in perception+20 dB Four times as loud+ 10 dB Twice as loud+5 dB Readily perceptible increase+3 dB Barely perceptible increase0 dB Reference-3 dB Barely perceptible reduction-5 dB Readily perceptible reduction-10 dB Half as loud-20 dB One quarter as loudTABLE 1.1: Perceptions of LoudnessInternational Students’ Conference of Civil Engineering, ISCCE 2012, 10-11 May 2012, Epoka University, Tirana, Albaniafrequency range, emphasizing frequencies in the most sensitive range and deemphasizingfrequencies out of the sensitive range.1.2. Sound Pressure LevelIt has been found convenient to use a logarithmic function to quantify sound and noise. Thisfunction is termed the Sound Pressure Level (SPL) and it is defined in the equation below.The SPL is a function of the ratio of the square of the sound pressure of a given sound to thesquare of a reference sound pressure. In fact, the reference sound pressure is the smallestsound that young, good ears can just hear, i.e., 20 Pa. As also shown above, the unit of theSPL is decibels; abbreviated to dB (A dB is a relative scale, in this case relative to P0, thereference sound pressure)where SPL is the sound pressure level (dB re P0), P is magnitude of pressure fluctuations(Pa) and P0 is the magnitude of a reference pressure is 20 Pa.Typical values of Sound Pressures and their accompanying SPLs are given in Table 1.2. Itis generally accepted that an increase in SPL of 3 dB is about the smallest change that can bedetected by the human auditory system.1.3. Environmental NoiseEnvironmental noise sources may include one or more of the following attributes.Propagation paths can vary widely:• Along roads• Over parklands and outdoor spaces• Over barriers, walls or hills• Through building elements such as windows.Some descriptors that have commonly been adopted in many countries include the following.• Leq - The energy equivalent level of the noise being investigated.• L10(1h) - The noise level exceeded for 10% of a 1-hour period. This is usuallyregarded as quantifying the average maximum level of the noise beinginvestigated.Apparent loudness Sound Pressure (^ Pa) Sound Pressure Level (dB) SourceDeafening 200,000,000 140 Jet aircraft130 Pain thresholdVery loud 20,000,000 120 Loud horn at 1 m2,000,000 100 Noisy factory200,000 80 Noisy officeLoud 70 Average street noise20,000 60 Average officeModerate 2200 40 Private officeFaint 200 20 Rustling leaves10 Normal breathingVery faint 20 0 Hearing thresholdTABLE1.2:Typical Sound Pressures and Sound Pressure LevelsInternational Students’ Conference of Civil Engineering, ISCCE 2012, 10-11 May 2012, Epoka University, Tirana, Albania• L90(1h) - The noise level exceeded for 90% of a 1-hour period. This is usuallyregarded as quantifying the background or ambient noise level and ismeasured in the absence of the noise being investigated.2. ROAD TRAFFIC NOISEAs set out above, road traffic is a majorsource of noise to which the community isexposed.From a technical perspective, road trafficnoise maybe regarded as the aggregation ofthe noise produced by individual vehicles inthe traffic stream. The major factors thatinfluence the generation, propagation, andreception of traffic noise are listed in Table1.3 below.2.1. Pavement Effects on Road TrafficNoiseRoad type is another important factor in the generation of traffic noise, especially given thesignificance of tire/road interactionamongst the sources of vehicle noise, asdescribed previously. It is clear that there isa considerable range of noise levelsproduced by these pavements. Both thisrange and the relative performance of thepavement types included are comparableand similar to those determinedinternationally. The pavement typesincluded in Table 1.4 are common and arebriefly described below.2.2. Calculation of Road Traffic NoiseThere are many traffic noise prediction models and associated computer software packagesavailable around the world. Most of the models perform to a generally similar degree ofaccuracy. One popular and widely known model is known as CoRTN — the Calculation ofRoad Traffic Noise. The CoRTN model is relatively simple in construct, is well tried andtested and is rather typical of many traffic noise prediction models available around the world.According to this method it is assumed that:OrTechnical Aspectof Traffic NoiseMajor Influencing FactorsGeneration Traffic volumeTraffic speedTraffic compositionTraffic operating conditions(free or interrupted flow)Road typeRoad surfacePropagation Ground coverSource-receiver distanceScreeningWeather and atmospheric conditionsReception Receiver location (in or outside)Ambient noise conditionsTABLE 1.3:Major Factors Associated With RoadTraffic NoisePavement Type Average Variation inTraffic Noise (dB(A))14 mm Chip seal + 4Portland cement concrete withlateral tynes and draggedsurface finish+ 2.5Cold overlay slurry seal + 2Dense graded asphalticconcrete0Stone mastic asphaltic concrete - 2Portland cement concrete withexposed aggregate surface3Open graded asphaltic concrete - 4TABLE 1.4 Average Variations in Pavement NoiseInternational Students’ Conference of Civil Engineering, ISCCE 2012, 10-11 May 2012, Epoka University, Tirana, AlbaniaFigure 1.1: Level ground with noise barrier3. NOISE BARRIERSNoise barriers need to be considered in the context of providing effective noise relief, whilealso addressing issues of appearance, urban design, site constraints, maintenance (includingwhole-of-life costs), safety, graffiti, cost (value- for-money) and sustainability.3.1. LocationIn principle a noise barrier is mosteffective located as close to the road aspossible (Figure 1.1). However, for aroad located in a cutting it is better toplace the barrier at the top of thecutting, where it will have a greatereffect.3.2. HeightThe height of a noise barrier is also akey parameter. Generally the higher thebarrier, the greater is the level of noisereduction. As a general rule, a noisebarrier should at least be high enough toblock the line-of-sight from a house tothe engines of vehicles on a road. Thisline should be assessed from a point 1.5 meters above the floor of an adjacent house to thefurthest point 1 meter above the road surface.When a noise barrier just breaks the line-of-sight between the noise source and the receiverthere is approximately 5 dB attenuation of noise.For multiple-lane roads, the noise from the furthest traffic lanes will not be reduced by a noisebarrier as much as noise from the nearest lanes because of the different path angles, unless theroad is on a bridge or embankment above houses.3.3.ReflectionsMultiple reflectionsbetween parallel noisebarriers, or betweenbarriers and high sidedvehicles, can reduce thebenefit of a barrier.It is possible to reducethe acoustic reflectivityof a noise barrier by using an absorptive material (e.g. mineral wool or fiber glass) with anappropriate facing. Alternative absorptive materials include "hard" surfaces that are porous orhave resonant cavities. A rule-of-thumb is that sloping a noise barrier outwards by as little as7° reduces the impacts of reflections. Another approach could be to maintain a vertical barrierFigure 1.2: Line-of-sight and the noise barrier shadowzoneFigure 1.3: Tilted noise barriers can direct noise awayfrom the receiverInternational Students’ Conference of Civil Engineering, ISCCE 2012, 10-11 May 2012, Epoka University, Tirana, Albaniabut use a relief pattern with angled component geometry to achieve an upwardly dispersedreflection.3.4.Top shapeModifying the shape of the top edge of a noisebarrier can increase the performance of thebarrier without increasing the height andassociated visual impacts. Shapes include T-tops,Y-tops, pear-shaped tops, cantilevered walls andothers. Given the same total height of wall, thesecan improve barrier attenuation by 1 to 10 dB.Figure 1.4 shows some different barrier tops.3.5.LengthDiffraction of sound occurs not only at the topedge of a barrier but also around the ends. Assuch, the length of a noise barrier is important.A rule-of-thumb to determine the required lengthof a noise barrier is that it must cover ahorizontal angle of 160 degrees viewed from thereceiver (Figure 1.5)4.MATERIAL SELECTIONThe intention of this section is to provide a summary of general design advantages anddisadvantages for transparent panels that may be used in noise barriers, because we havetaken these panels to be a part of our study.4.1Transparent panelsFigure 1.4: Different top shapesFigure 1.5 Noise barrier lengthType of Barrier Advantages DisadvantagesPolycarbonate Cost (initial and whole-of-life)Virtually unbreakableuV resistantSelf-extinguishes when in contact withfireProne to discolorations & yellowingCan be scratchedUse of anti-etching films problematicCombustible (emits toxic gases such ascarbon monoxide but is self-extinguishing)Permanent proprietary anti-graffiti coatings areexpensive (manufacturers' warranties may beaffected by use of non-proprietary anti-graffiticoatings)Less established than other transparent materials5.CASE STUDYROUNDABOUT NEAR WORLD TRADE CENTER – PRISTINAAs set out above, in this paper is stated and taken into account a critical point and a source ofnoise in the center of Pristina. It is the main roundabout that interlinks four main roads. In theside of it is being built a huge office and administrative building. The distance between theroundabout and the building is around 10-15 m. Because the distance is too short, and thenoise is too high, it was necessary to make an assessment and to calculate the noise pressurein the building.At the first time, according to studies made before, we have taken some site measurements.Because it is a new thing, and its just an abstract, the device we used to take themeasurements was a simple microphone, recording the sound at 48000 samples/sec, and usingAndroid App – Noise Metter for saving the logs. After that, the log was put into an Excelworksheet, and from there built the noise graph with two different values (normal and peakvalue).The measurements are taken in the peak hour, when the traffic volume is around 6800vehicles/hour, and the noise was recorded every two seconds. See the graph below.Figure 1.6: Log and Chart of the Traffic Noise Measurement in the roundaboutAcrylic Impact resistance - comes with option offilament reinforcement.Scratches can be polished out. May bepossible to flame polish.uV resistantWell established internationally forroad- traffic noise barriersEasy to scratchUse of anti-etching films problematicCombustible (burns to completion unlessExtinguished)Permanent proprietary anti-graffiti coatings areexpensive (manufacturers' warranties may beaffected by use of nonproprietary anti-graffiticoatings)Glass Harder to scratch than polycarbonate oracrylicScratches can be polished outNot combustibleMore compatible with use of anti-etching filmEstablished material for road-trafficnoise barriersUV resistantRelatively easy to smash/shatterExpensiveManufacturers' warranties may be affected by use ofnonproprietary anti-graffiti coatingsFire may cause glass to shatterFurthermore, the Leq is calculated using the same equations mentioned above, and at the end,the barrier is designed. The transparent polycarbonate barrier is selected. Below are shown thedetails of measurement, noise waves acting on building and reduced noise with barrier.REFERENCES[1] S. Samuels, (2006) Road Traffic Noise. The Handbook of Highway Engineering, Taylor &Francis Group, Florida, FL, USA[2] Judith L. Rochat, (2004) Transportation Noise Issues. Handbook of TransportationEngineering, McGraw-Hill, New York, NY, USA[3] Simeon Kean, (2008) Is CoRTN an Leq or L10 Procedure? Research and Development,Bassett Acoustics, AAS ‘08, Sidney, AUSTRALIA[4] NZ Transport Agency, (2010) State Highway Noise Barrier Design Guide, NZTA,Wellington, NEW ZEALAND

Traffic noise in urban and regional roads and impact on the administrative facility P+30 in Prishtina

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Traffic noise in urban and regional roads and impact on the administrative facility P+30 in Prishtina

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