مدلسازی آلودگی صوتی در یک تقاطع شهری (نمونه موردی: شهر قزوین)

هدف از انجام مطالعه آلودگی صوتی، بررسی رابطه آلودگی صوتی با خصوصیات ترافیکی و محیطی است. بدین منظور با استفاده از روش مدلسازی رگرسیون خطی چندگانه روابطی به دست می‌آیند که بتوانند میزان شدت صوت را بر اساس خصوصیات ترافیکی وسایل نقلیه نظیر حجم، سرعت، فاصله و زمان‌بندی چراغ‌های راهنمایی برآورد کنند. داده های فوق با استفاده از آماربرداری در محل و همچنین استفاده از داده های ترافیکی حاصل از نرم افزار مدیریت چراغ (scats) و دوربین های نظارتی مرکز کنترل ترافیک شهر قزوین بدست آمده است. همچنین تاثیر هر یک از متغیرها و اهمیت آن در آلودگی صوتی بررسی شده و بر اساس آن راه حل‌هایی برای کاهش آلودگی صوتی به دست می‌آید. در این مطالعه که در یکی از تقاطعات مهم شهر قزوین صورت گرفت، داده‌ها شامل تراز صوت معادل، حجم وسایل نقلیه به تفکیک نوع آن‌ها، زمان‌بندی چراغ راهنمایی در زمان برداشت، فاصله نقطه برداشت تا مرکز تقاطع، و تعداد بوق خودروها در زمان برداشت بودند که این داده‌ها در 94 نقطه طی دو برداشت یک‌دقیقه‌ای در هر نقطه به دست آمدند. نتایج مدلسازی نشان داد که مهم‌ترین متغیرهای تاثیرگذار در تراز معادل صدا شامل حجم وسایل نقلیه به‌خصوص وسایل نقلیه سنگین و نیمه سنگین با تاثیر مثبت (با تاثیر میانگین 0.025، 0.125، 0.525، و 0.489 به ترتیب برای سواری شخصی، موتور، کامیونهای نیمه سنگین و سنگین)، زمان سبز رویکرد نزدیکتر به تقاطع و تعداد بوق‌هایی که در این زمان به صدا درمی‌آیند با تاثیر مثبت (به ترتیب 0.04 دسی‌بل بر ثانیه و 0.08 دسی‌بل بر هر بار به صدادرآمدن) در این تقاطع هستند. 

modelling noise in an urban intersection (a case study: qazvin)

recent advances in technology of all disciplines bring some disadvantages, such as environmental problemsjust to name one among many. environmental consequences of modernization could appear in different formsbut generally speaking they are categorized to five major classes of air pollution, water contamination, soilcontamination, warming and noise pollution. there has been a significant increase in noise pollution fromman-made sources over the past 100 years, which now doubles every 10 years. therefore, a rigorousevaluation of problem, useful engineering approaches as well as a thoughtful and meticulous planningdecisions to control noise pollution and its harmful effects is an essential agenda for each community. noisepollution that is different from other types of pollution due to its source and emission characteristics. in urbanareas, the engine and exhaust system of cars, light trucks, buses and motorcycles is an important source ofnoise pollution, that have major environmental impacts. traffic noise pollution is the most important sourceof environmental noise pollution in cities. the main objective of the paper is to find the relationships betweennoise and traffic characteristics, and also to examine the impact of each one separately, so that we can findout the importance of each variable in noise pollution we will find suitable solutions to reduce the noisepollution. in this study, which was carried out at one of the important intersections of qazvin, data includingequivalent sound level, the volume of vehicles by type, traffic light timing at picked up time, distance frompicked up point to intersection center, number of honks at the time of picked up which is heard, that data wasestimated at 94 points, points were located at 10 m distance on the edge of the street and if there was an openspace, points were expanded, and there were two picked up for each point. the followings are some of themost important results of the modeling: distance has a great effect on the amount of sound received. byincreasing the distance from the center of the intersection, the amount of noise received and as a result, noisepollution is drastically reduced. proximity of intracity bus terminal as well as being at the entrance of thecity, the number of heavy and semi-heavy vehicles passing through this intersection has worsened thesituation of noise level. the green phase timing of each approach, and the use of horn by some drivers ingreen time to inform the driver closer to the intersection is one of the effective factors in noise pollution. ina nutshell, the results of modeling showed that the most important variables affecting the sound equivalentlevel includes the volume of vehicles, especially heavy and semi-heavy vehicles (with the impacts of 0.025,0.125, 0.526, 0.489 for cars, motors, semi-heavy vehicles and trucks, respectively,) the green time of theapproach 1 and the number horns honked in this period (with the impact of 0.05 db per second, and .08 dbper honk, respectively), are the variables that influence the equivalent sound level at this intersection. forimprovement of the intersection in terms of noise level, the intersection schedule can be changed in favor ofthe passage of heavy vehicles and buses, which of course requires the presentation and implementation ofaccurate planning of buses and heavy vehicles. it is also possible to provide traffic restrictions for the passageof heavy and semi-heavy vehicles during the day or during peak hours, as well as restrictions for motorcycletraffic in urban areas depending on the type of vehicle and its pollution standards.