Tranquillity by design Architectural and landscape interventions to improve the soundscape quality in urban areas exposed to aircraft noise Marinus (Martijn) Cornelis Lugten Supervisor: Professor Dr Koen Steemers Clare College Department of Architecture and History of Art Martin Centre for Architectural and Urban Studies Date of Submission: 12 December 2018 This dissertation is submitted for the degree of Doctor of Philosophy ii This dissertation is the result of my own work and includes nothing which is the outcome of work done in collaboration except as declared in the Preface and specified in the text. It is not substantially the same as any that I have submitted, or, is being concurrently submitted for a degree or diploma or other qualification at the University of Cambridge or any other University or similar institution except as declared in the Preface and specified in the text. I further state that no substantial part of my dissertation has already been submitted, or, is being concurrently submitted for any such degree, diploma or other qualification at the University of Cambridge or any other University or similar institution except as declared in the Preface and specified in the text. It does not exceed the prescribed word limit for the relevant Degree Committee Word count: 54.653 words (72.331 words including the abstract, preface, contents, literature and appendices) iii iv Abstract Title: Tranquillity by design - Architectural and landscape interventions to improve the soundscape quality in urban areas exposed to aircraft noise Name: Marinus Cornelis (Martijn) Lugten The noise emissions from aircraft negatively impact the quality of life for those in areas around airports. Excess noise levels can cause stress-related complaints, leading to adverse health effects. Although newer aircraft are significantly quieter than older models, aircraft noise pollution remains a problem. Literature suggests that the level of aircraft noise annoyance people experience is equally dependent on the level of disturbance induced by the sound and individuals’ perceived level of their own ability to cope with and control it. Traditionally, noise prediction models are used to determine the noise load around airports. If levels are deemed too high, building restrictions are put in place, and house owners are either bailed out or receive funding for acoustic insulation. However, literature on road traffic noise shows that the design of the environment that surrounds individuals has a great impact on their perception of noise annoyance. For instance, the design of buildings, streets and cities influence the propagation of sound around buildings. This can reduce or amplify the sound levels locally. Furthermore, the presence of natural features, such as trees and moving water, can evoke a more positive auditory sensation in areas exposed to traffic noise. Without changing the sound exposure levels, the sight and proximity of vegetation improves the individuals’ assessment of the soundscape quality and reduces the level of noise annoyance. Like landscapes, the perception of the acoustic environment, or soundscape, is the result of design choices. Nevertheless, the question remains as to whether the design of the built environment can yield a similar effect for aircraft noise. The doctoral research focused on this question, from both an acoustic and soundscape-perception perspective, and comprised four separate studies. The first study presents the results of a systematic in-situ measurement study, in which the sound attenuating effects of buildings exposed to aircraft noise were assessed. In the second chapter, the results from the first study were used to develop and test a method to predict the propagation of aircraft noise around buildings in a numerical acoustic model. The third study used the numerical model to compare the noise attenuation effects of building design parameters, namely height, form and cladding. The fourth chapter explored the perception of aircraft noise in urban areas with or without moving water and vegetation, using virtual-reality. Together, the four studies provide tools that can be used by architects and urban designers to improve the soundscape quality in areas affected by aircraft noise. Depending on the location and local acoustic situation, different alternatives are possible, which are supported by the results presented in this thesis. v vi Preface As a frequent traveller between Amsterdam and Cambridge, each time I travel to an airport I am amazed by the coming and going of the airplanes. Inevitably, the closer you get to the airport, the harder it is to escape from the noise. By arrival at the airport, the traveller is met by a cacophony of sounds from horns, car engines, trains, humans and airplanes. Although the sound levels are acceptable inside the airport’s terminals and gates, the levels are far less enjoyable outside the airport’s premises, especially when standing close to the runway. The rapid growth of civil aviation, , partly driven by the rise of low-cost carriers, has dramatically increased the number of flight movements above (European) cities. Unfortunately, flying comes at a price and erodes the quality of living in areas close to airports, not to mention the adverse impact of flying on our planet’s climate. Over the past three years, I have focused on the question what can be done to reduce aircraft noise in such areas. This dissertation presents the findings of this journey and shows that architectural and urban design can make strides forward in improving the quality of soundscapes exposed to aircraft noise. Moreover, the results could help airports and governments to amend and improve noise abatement strategies. However, in my opinion, the findings should not be simplified to a dull argument to legitimize the expansion of air traffic without further debate and scrutiny. Neither will the results lose their credibility and applicability if the number of air traffic movements would stabilize or fall. In the first place, I hope that the research will be used in good faith, with the intention to serve the interests of those who face the negative side of air traffic day by day. Secondly, I hope that the research will contribute to the quality of life in airport regions. Finally, I declare that this dissertation is my own work and contains nothing which is the outcome of work done in collaboration with others, except as specified in the text and acknowledgements. The work in this thesis is not substantially the same as any that I have submitted, or, is being concurrently submitted for a degree or diploma or other qualification at the University of Cambridge or any other University or similar institution except as declared in the Preface and specified in the text. I further state that no substantial part of my dissertation has already been submitted, or, is being concurrently submitted for any such degree, diploma or other qualification at the University of Cambridge or any other University or similar institution except as declared in the Preface and specified in the text. The dissertation does not exceed the prescribed word limit for the relevant Degree Committee. Cambridge, 7 December 2018 vii Nomenclature SPL sound pressure level in dB OASPL overall A-weighted sound pressure level in dB(A) 1/3-OB 1/3-octave band p air pressure in Pa -5 pref reference air pressure (2∙10 Pa) Lden sound pressure level day-evening-night, European noise metric Lmax maximum sound pressure level in dB Leq equivalent sound pressure level in dB LAmax A-weighted maximum sound pressure level in dB(A) LAeq A-weighted equivalent sound pressure level in dB(A) LA50 median A-weighted sound pressure level in dB(A) (i.e. based on dB(A) levels, not the sound pressure) SEL Sound Exposure Level IL Insertion Loss in dB FFT Fast Fourier Transform NPD Noise Power Distance ADS-B Automatic Dependent Surveillance-Broadcast VCNS Virtual Community Noise Simulator ICAO International Civil Aviation Organization FAA Federal Aviation Administration ECAC European Civil Aviation Conference INM Integrated Noise Model (FAA’s aircraft noise prediction model) doc.29 document 29 (ECAC’s aircraft noise prediction model) nLOS building side facing away from the flight path (no line of sight) dLOS building side towards the flight path (direct line of sight) shielded facade see nLOS (interchangeable) exposed facade see dLOS (interchangeable) AAS Amsterdam Airport Schiphol NLR Netherlands Aerospace Centre viii Contents Abstract ..................................................................................................................................................................................... v Preface ..................................................................................................................................................................................... vii Nomenclature ......................................................................................................................................................................... viii Introduction 1. Introduction and research outline ................................................................................................................................... 1 1.1. Prologue ................................................................................................................................................................. 1 1.2. Introduction ...........................................................................................................................................................