The acoustic climate of spaces located under overpasses in the context of adapting them for outdoor public events – a pilot case study

Due to the current shortage of traditional public space because of its privatization, commercialization, and securitization, there is an urgent need to reclaim areas affected by motorized traffic in the urbanized areas. On the other hand, the process of adapting them for new purposes should be carefully carried out, addressing several issues, among them environmental acoustics. This study is meant to contribute to our understanding of acoustic conditions of a general model of the bridge underspace. Therefore, the aim of the research was to examine the existing acoustic climate by measuring noise levels and comparing them with equivalent acceptable noise levels for the expected type of space development and Noise Rating curves. In this research, a pilot case study approach was used, as measurements were taken for a chosen space located under an elevated road that represents certain criteria set by the researchers. The results allowed us to: (1) verify the relationship between the geometry of the bridge underspace and the noise levels, (2) assess the initial acoustic conditions in terms of possibilities of acoustic adaptation of the examined space for outdoor public events, and (3) formulate hypotheses and preliminary assumptions for the planned further and broader studies of the issues raised in this article. The presented results and their analysis show that it is possible to bring the acoustic conditions in the studied space to the state required for public or cultural meeting spaces. In comparison with earlier findings, the research undertaken appears to be pioneering and the results can be used as valuable input for further research on this topic.

Reform and Practice of Immersive Teaching in Environmental Acoustics

Environmental Acoustics is a professional course that educates students majoring in Acoustics. Affected by practical equipment and other factors, the teaching effect of knowledge points relevant to subjective auditory perception contained in the course is poor. Taking the course of Spatial Hearing and 3D Stereo as an example, this study develops a virtual simulation experiment system for the topic of subjective hearing perception in order to carry out the reform and practice of immersive teaching. Combined with the virtual simulation experiment project with high sense of presence, students are supported by the actual auditory perception effect in the whole learning process and have achieved good learning effect.

Proacustica Handbook: noise and vibration control in building installations

Proacústica is a nonprofit entity created in 2010 to congregate companies and professionals willing to leverage the development of acoustics in Brazil. Three technical committees (TCs): Environmental Acoustics, Building Acoustics, and Room Acoustics, contribute to the drafting of laws, standards, production of technical content, and integration between different players of the market. By 2021, the Room Acoustics TC incorporated three Working Groups: Special Rooms, Schools and Noise Control and Vibration Control - the last one dedicated to the Proacustica Handbook: Noise and Vibration Control In Building Installations. The purpose of this publication is to describe the step-by-step measures to implement noise and vibration control strategies in buildings. These strategies are aimed at the particularities of the Brazilian market at the moment and also a way to improve how M/E/P equipment manufacturers, installers, designers, and acoustic consultants approach the subject from the design to the construction, Important technical discussions among participants included: the use of sound pressure versus sound power data for equipment; the sound rating for diffusers, VAVs, and other ductwork devices; vibration isolation guidelines, among other topics. This paper presents the Handbook structure, relevant discussions, and recommendations to be published as a final document by the end of 2021.

Insertion loss (IL) of finite sound barriers of different contours - An introduction to geometrical solutions in 3-D space

The design of finite sound barriers noise sources and control points requires calculations beyond those that are used when the Maekawa formula is applied, since the problem involves polygon sd barriers located in various possible orientations in 3D space. We present here some means that are linked to basic mathematical geometrical tools. Those means are relatively simple, as compared to the physical formulation of the relevant diffraction solutions for sound barriers (e.g. Rosenhouse, 2019, 2020). Such calculations can apply algebraic, trigonometric or vector analysis and their combinations to define the geometries of barrier IL. This approach includes the location of the sources and control points, which are essential as data for finding IL and other issues of environmental acoustics. We will show solutions including results of IL for a common rectangular barrier, as compared to IL of a barrier with a sloped top and side, among other possibilities.

Analysis of the interaction of helmholtz resonators in periodic acoustic metamaterials depending on its orientation with the acoustic source.

Acoustic screens based on sonic crystals constitute one of the most promising technological bets of recent years in the field of environmental acoustics. Sonic crystals are defined as new materials formed by arrays of acoustic scatterers embedded in air. The design of these screens is made using powerful simulation models that provide reliable results without the need of expensive experimental testing. This project applies the finite elements method in order to analise an acoustic barrier that includes (Helmholtz) resonators in its scatterers, and studies the interference of the sonic crystal with the effect of the Helmholtz resonator, depending on its orientation with the acoustic source.

Human Environment Acoustics in Bauman Moscow State Technical University: Yesterday, Today, Tomorrow

The history of "Environmental Acoustics" research area development in the activities of the Bauman Moscow State Technical University’s "Ecology and Industrial Safety" chair in general from the end of the nineteenth century to the present time has been described. Much attention is paid to the activities of E.Ya. Yudin (as the creator of the technical acoustics scientific school at the chair) and his students as well. Have been presented the main areas of carried out at the chair research works (both theoretical and practical), related to problems of noise and vibration reduction. Have been considered the issues of technical acoustics teaching in the framework of the recently created "Environmental Acoustics" master's program, as well as the prospects for this area development at the chair in the near future.

KAJIAN PERUBAHAN RUANG DAN SOUNDMARK KAWASAN WISATA PUSAKA TAMANSARI YOGYAKARTA

Title: Study of Space Changing and Soundmark in Tamansari Heritage Tourism Area, Yogyakarta Tamansari area is an area of historical value. Until now, this region has been conserved and used as a heritage tourism. The Tamansari site, which has not been used anymore since the reign of Sultan Hamengkubuwono III, has caused the growth of residential areas around it. This causes a change in the solid void of the Tamansari area. Changes in the existing building structure create differences in the soundscape of the area that was once the location of the palace retreat and is now a heritage tourism area. In this study will discuss the changes that occur in the mass management of buildings in the Tamansari area that will affect the environmental acoustics of the area. This research method uses qualitative deductive method by comparing the shape of the space during the active period of the building as the resting of the Keraton family with the current building mass discussed with the theory of space and acoustic environment. The results of this study are changes in ground figures and linkages showing changes in the soundmark of the Tamansari area. Changing ground figures make the impact of increasingly diverse activities appear. Soundmark changed from the dominant calm voice to the nois dominant. The soundmark area changes from sounds that support a sacred atmosphere with sounds that are due to building density. This change in soundmark creates a change of sense of place from the Tamansari area.