도시 소음 관리하기: 더 조용한 도시를 위한 전략

### 건전한 도시를 위한 디자인: 소음 공해를 완화하기 위한 전략
* 🔊 "소음을 덮는다고 해서 소음을 잠재울 수는 없습니다."라고 말하며 **도시 소음 공해를 효과적으로 관리하는 것이 얼마나 어려운 일인지** 설명합니다.
* 🏙 뉴욕과 같은 도시는 시끄럽기로 악명이 높으며, 개인의 청력 문제보다는 **설계 결함**으로 인해 음향 환경이 열악해지는 경우가 많습니다.
* 🌳 전문가들은 교통 소음을 줄이기 위한 최선의 방법은 **센트럴 파크 설계에 적용된 원칙인 번잡한 도로와 주거 지역을 분리하는 것**이라고 제안합니다.
* 🛠 역사적으로 조용한 공간에서 소리를 반사하기 위해 표면을 재구성하고 장벽을 추가하는 등의 기술을 사용해 **공원을 주변 거리보다 훨씬 덜 시끄럽게 만들었습니다.**
* 🚆 지하철 시스템에서 열차의 진동은 지면과 건물을 통해 전달될 수 있지만 엔지니어는 **탄력 있는 소재를 사용하여 선로를 단열**함으로써 이를 완화할 수 있습니다.
* 🎧 기차역의 흡음 처리는 **소음을 줄이고 안내 방송의 명료도를 개선**하여 승객의 편안함과 의사소통의 명확성을 모두 해결합니다.
* 🏗 도시 환경이 밀집되고 다양한 소음이 증가함에 따라 **공사 및 기타 방해가 되는 활동으로 인한 소음을 관리하는 것**은 매우 중요합니다.
* 📏 건물과 공공장소의 사전 예방적 설계는 삶의 질을 높이기 위해 음향을 고려해야 하며, **도시가 소음 기준을 채택하고 시행**해야 할 필요성을 강조합니다.

도시는 더 나은 건강과 삶의 질을 위해 소음 공해를 관리할 수 있도록 선제적으로 설계해야 합니다.

(music box clicking) - [Narrator] You can't silence a noise by covering it up. You can still hear the music box; that's because the vibration is still traveling into the table. - [Narrator] It's much better to cover it

and insulate it from the table, but you may still hear it because it's much harder to silence noise without removing the source. From trains to traffic, planes, and more, cities are incredibly loud. Often, people will blame themselves for not being able to hear correctly in a space,

but it's often the result of poor design. (upbeat band music) - [Narrator] New York City is one of the loudest cities in the world, so we asked acoustics expert Raj Patel to explain how Metropolis, like New York City,

can actually quiet noise pollution, and whether it could ever stop being so loud. (rhythmic music) If you could design a city from scratch, the best solution to traffic noise would be to separate busy roads from areas where people live or work.

Since that usually isn't an option, a more practical option is to separate these areas by reshaping the city's surface or adding barriers, like designers used in the 1850s when they built New York's Central Park. As you come into the park,

you drop quite significantly, by about 10 feet. This wall helps to reflect the sound from the street back away from the park itself, to try and create a calm environment in the park. - [Narrator] Because of this, the park is much less noisy than the street.

Historically, experts recommended limiting environmental noise exposure to 70 decibels, averaged over a 24-hour period. It isn't enough to just line roads with a thin layer of trees or plants; sound can go straight through.

It's important to modify the terrain. We improve over the at-grade flat scenario by creating some sound mitigation here where we both absorb the sound and reflect some of it back out over the highway. It still means that some of our sound sources

travel straight through here.  You can even take this a step further. In this scenario, we changed the grades between the road and the building. We've improved the situation of the barrier, which is sending sound back out towards the street.

But sometimes the situation is much more complicated, like when Raj's team helped design Little Island, a park directly off Manhattan's West Side Highway. It's located right next to an industrial site

adjacent to a large construction site; you have four lanes of highway running all the way through. So they planned the shape of the island and its plants to block sound from reaching key areas of the park, like its main lawn, playground,

and performance spaces. The wind coming through the trees creates a backdrop that starts to mask the sound of the West Side Highway, and the sound levels reduce further as you move towards the west. It was an opportunity to bring some of the key learning

From the design of Central Park, we use similar principles to try and achieve optimum sound conditions in the new park. - [Narrator] Fixing a city's noise problem also has to consider sound below street level, (train whizzing)

In public transit systems, as carts move at high speeds on these rails, the whole system creates noise.  It's not just a problem for people on the train platforms. - The wheel-rail interaction in a subway system results in vibration traveling through the tunnel.

It then travels through the ground to the footings of nearby buildings, and then travels up through the building as vibration, and then that energy converts into sound. - [Narrator] This is why some people who live above subways can hear and feel rumbling as trains go by,

but it doesn't have to be this way. Engineers can counteract the loudspeaker effect by insulating the tracks from the ground. Raj works for a firm that helped design New York City's Second Avenue Subway Extension.

What they did was attach the rails to resilient fasteners that minimize how much vibration reaches the wider system. - It's a squishy material designed to absorb the vibration of the rail before it travels into the surrounding track slab.

When completed, it looks like this. - [Narrator] Another important fix is adding sound-absorbing treatment to stations. Train platforms are typically constructed with concrete and tile to make them durable and easy to clean, but these materials also reflect sound,

and make track noise significantly worse. So this project, the 96th Street station at the Second Avenue Subway, incorporates sound-absorbing treatment located between all of the beams here. So any sound that reflects from the walls is directed towards the ceiling,

and any noise from the trains themselves also gets absorbed in that location. - [Narrator] Improving train acoustics is also important so passengers can understand announcements. - [Raj] In an ideal world, speech is clear and intelligible

- [Announcer] Please allow all passengers to exit the train. - As we add reverberation in a room, that word becomes harder and harder to understand. - [Announcer] Please allow all passengers to exit the train.

- The other impact is noise. A little bit of noise is okay, but the more noise you have, the more difficult that becomes. - [Announcer] Please allow all passengers to exit the train. Add to that, reverberation,

- [Announcer] Please allow all passengers to exit the train. - [Raj] and you start to get a significant problem. - [Narrator] But lots of the time, the noise that bothers people the most,

doesn't come from permanent infrastructure; it comes from construction or other people. The sounds that people tend to find most disruptive are either repetitive and impulsive (drill thumping) – a beat that keeps on repeating itself over a period of time,

or things that are very tonal. So they have a single pitch and a single sound that continues for a long duration. Our ears are most sensitive to sound, where most of the information in speech is contained, and that's between about 500 hertz and 2 kilohertz,

which is somewhere between the middle and the upper three-quarters of a piano keyboard.  - [Narrator] As cities grow, it's increasingly important to manage noise levels because so many different things are happening in a city block at once,

it's important to understand how a project will affect its neighborhood and how surrounding noise will impact it. Arup simulates the acoustics of future projects with a facility called its Sound Lab. (gentle rhythmic music) It immerses clients in spaces

that haven't physically been built yet. - [Raj] We use this to listen to almost every project that we design now. (paper thumping) - [Narrator] In the case of Brooklyn Steel, a concert venue in New York City, for instance,

it helped the venue figure out how to convert a former steelworks factory into a massive music venue. - Almost all of the wall surface in this building is covered in two-inch-thick sound-absorbing material. By having good room acoustics,

that means the sound engineers in the building don't have to push the sound levels higher than they need to, to combat reverberation in the room. The second really important component here is the sound system. A line array is designed and electronically controlled

To beam sound directly to the audience where you need it, and to ensure that no sound goes where you don't need it. - [Narrator] They also added a one-foot perimeter wall around the performance space, and only one side is an exterior wall.

They also added a roof four feet above the existing roof and covered it in grass and plants, which further insulates noise that could otherwise escape. Similar roofs have been built in many sports arenas, from Barclays Center to the University of Notre Dame Basketball Stadium.

Noise pollution can have a huge impact on health and quality of life, causing stress and increasing the risk for heart disease and other issues. But while engineers have more and more tools to address the problem, some cities may need to write and enforce standards

so these tools actually get used. - It requires a proactive approach to thinking about how buildings and people exist in harmony with each other, and how you make noise and acoustics an integral part of that thinking. (train whizzing)

Acoustic Engineer Fixes NYC Subway, Parks and Buildings to Limit Noise | WSJ Pro Perfected

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소음 제거의 과제와 소스 제거의 중요성

소음원을 덮는다고 해서 소음이 제거되는 것이 아니라 진동이 계속 전달됩니다.

도시는 다양한 소스로 인해 엄청나게 시끄럽고, 잘못된 설계로 인해 소음 문제가 발생하는 경우가 많습니다.

뉴욕시의 소음 공해와 잠재적인 해결 방안에 대해 논의합니다.

소음 저감을 위한 도시 설계 전략

번잡한 도로와 주거 지역을 분리하는 것이 이상적이지만 현실적으로 불가능한 경우가 많습니다.

센트럴 파크의 디자인에서 볼 수 있듯이 도시 표면을 재구성하거나 장벽을 추가하면 소음을 완화하는 데 도움이 됩니다.

지형을 변경하고 효과적인 방벽을 사용하는 것이 중요하며, 단순히 나무를 심는 것만으로는 충분하지 않습니다.

도로와 건물 사이의 경사도를 변경하면 소음 저감 효과가 더욱 향상됩니다.

리틀 아일랜드의 디자인처럼 복잡한 상황에서는 소리가 주요 영역에 도달하지 않도록 차단하는 통합 계획이 필요합니다.

대중교통 시스템의 소음 공해 문제 해결

고속철도 시스템은 지면을 통과하여 건물로 이동하는 소음과 진동을 발생시킵니다.

트랙을 지면으로부터 절연하면 라우드스피커 효과를 상쇄할 수 있습니다.

탄력적인 패스너는 뉴욕시 2번가 지하철 연장선에서 진동 전달을 최소화합니다.

스테이션의 흡음 처리는 소음 반사를 줄이고 음향을 개선합니다.

열차 음향을 개선하면 안내 방송이 명확하게 전달되고 승객의 이해도가 높아집니다.

반복적이고 충동적인 소리와 음조 소리는 특히 방해가 됩니다.

사람의 귀는 말소리 범위 내의 소리 주파수에 가장 민감합니다.

도시 프로젝트의 음향 시뮬레이션 및 설계

프로젝트가 이웃에 미치는 영향과 그 반대의 영향을 이해하는 것은 매우 중요합니다.

Arup의 사운드 랩은 향후 프로젝트의 음향을 시뮬레이션하여 선제적으로 조정할 수 있습니다.

브루클린 스틸의 디자인은 흡음 소재와 정교한 사운드 시스템을 통합했습니다.

라인 어레이 사운드 시스템은 청중에게 정확하게 소리를 전달하여 원치 않는 소음을 최소화합니다.

외곽 벽과 식재된 지붕을 통해 추가적인 소음 차단을 구현했습니다.

노이즈 제어의 광범위한 영향과 필요성

소음 공해는 건강과 삶의 질에 부정적인 영향을 미칩니다.

조화로운 환경을 조성하려면 소음 제어를 통합하는 사전 예방적 도시 계획이 필수적입니다.