Measurement and simulation of room acoustics parameters in traditional and modern bath buildings

This paper presents the results of a number of case studies concerning measurement and simulation of room acoustical parameters in both historical and contemporary instances of bath spaces. Historical instances of such spaces are, in our study, traditional hammam (bath) buildings in Mediterranean and north-African countries (Algeria, Morocco, Syria). Modern instances include a modern hammam, a spa, and an indoor swimming pool in central Europe (Austria). The analysis is based on data obtained from measurements and simulations of pertinent indicators of room acoustic quality in such spaces. The results of the analysis permit the identification of certain salient features of room acoustics in highly humid spaces and corresponding technical challenges (e.g., excessive reverberation and high noise exposure). Moreover, the results allow for the statistically grounded estimation of uncertainties in simulation of room acoustics in architectural spaces.     

Measurements and predictions of room acoustics in atria

This study compares the acoustical measurements and simulation results of five atria with different designs. In each, atrium reverberation times and sound distribution patterns were obtained via measurements. Independently, we modelled these spaces using a room acoustics simulation application. The comparison of measurements and simulation results support the formulation of recommendations toward a more reliable use of modelling tools for proper acoustical design and analysis of atria.     

音乐厅的音质与建筑

本文对音乐厅音质设计中几项主要的音质参量及其主观属性间的关系进行分析研究。综合比较矩形和环绕形两类音乐厅的音质,探讨大厅音质设计与建筑设计间的密切关系。     

广州白云国际会议中心世纪大会堂声学设计综述

对广州白云国际会议中心D幢2600座世纪大会堂的建筑声学设计做了相关的综述,着重介绍了大会堂观众厅的形体调整、室内声学设计、建筑机电设备的噪声与振动控制等内容。室内声学设计过程中,利用室内声学计算机模拟分析这一辅助设计工具,对大会堂观众厅的声场特性及其对应各项音质的物理参量进行了模拟分析计算,对声学初步设计所提出的音质设计方案进行了论证,为厅内的室内声学设计提供了优化和调整的依据。文中对完工后的声学测试结果和使用后的主观音质效果也进行了阐述。     

重庆大学建筑城规学院多功能厅室内建筑声环境研究

重庆大学建筑城规学院多功能厅是学院师生进行会议、学术报告的主要场所。本文介绍了该多功能厅的室内概况以及主要建筑声学评价参数的测量结果,并用ODEON软件对厅堂室内音质参数进行模拟分析研究;同时分析了报告厅室内建筑声学环境特点,提出建筑声学改造措施。     

Ecotect软件在音乐厅改造中的模拟声学设计研究

以旧有体育建筑改造成音乐厅为例,本文通过分析原建筑的声学缺陷,初步设定可行的声学改造方向,然后应用Ecotect软件进行计算机辅助设计。通过模型的建立及各种声学环境的模拟之后,对所得数据进行比较分析,最终得到声学效果最为理想的改造方案。本文是一次对建筑设计新技术应用的探索,也为音乐建筑的前期设计提供切实的理论和数据依据。     

上海东方艺术中心交响乐厅室内声场计算机模拟分析

通过室内声场计算机模拟这一厅堂音质辅助设计工具，对现阶段交响乐厅的声场特性及对应各项音质的物理参量进行了分析计算，对声学初步设计所提出的音质设计方案进行了论证，以便与后续的缩尺模型实验结果进行对比分析，为本厅的建筑声学设计提供优化和调整的依据。     

中国古代声学在建筑中的应用

对建筑声学进行了介绍,对中国古代音质设计和中国古代的隔声进行了探讨,以提高人们对古代声学的认识和研究,从而促进现代建筑声学的发展,使声学技术更好地为建筑服务。     

Interaction formulae for members subjected to bending and axial compression in EUROCODE 3—the Method 2 approach

The final version of EN1993-1-1, EUROCODE 3 [EN1993-1-1. Eurocode 3. Design of steel structures, general rules and rules for buildings. 2005] for Steel Structures provides two alternatives for the buckling check of members subjected to axial compression and bending by interaction formulae, which are called there Method 1 and Method 2. This paper presents the characteristics, the background and the use of Method 2. The analogous presentation of Method 1 has already been given in [Boissonnade N, Jaspart J-P, Muzeau J-P, Villette M. New Interaction formulae for beam-columns in Eurocode 3. The French-Belgian approach. Journal of Constructional Steel Research 2004;60;421-31].The Method 2 formulae have been derived on the basis of the general format of the interaction concept of existing codes, e.g. the ENV-rules; however with advanced numerical background and consistent classification of the buckling modes. In this respect new improved interaction factors were developed from a wide scope of numerical simulations and the concept of the formulae was focussed distinctly on describing the modes of in-plane and out-of-plane buckling for members susceptible to fail either in flexural buckling or in lateral-torsional buckling. As result two sets of formulae are provided, which each cover a clear scope of physical member behaviour. Hereby, the specific effects of intermediate lateral restraints—as often found in steel structures—have also been included.The Method 2 formulae aim at providing buckling rules with compact simplified interaction factors and transparent application for standard cases.     

Noise impact caused by electrical energy substations in the city of Curitiba, Brazil

This survey is intended to characterize the noise impact due to electrical energy substations in the city of Curitiba over the population living in their vicinity. This impact has been studied with the aid of a computational tool capable of mapping the acoustical field of substations and their vicinity. Several factors have been considered in this survey: (1) sound power of the transformers; (2) vehicle flow on the surrounding roads; (3) positioning of the firewalls, buildings and walls; and (4) terrain topography. Four substations have been analyzed, and an acoustical map has been traced for each of them. With these maps it was possible to visualize what was the incident noise level on the building facades. The predicted noise levels have been compared to the environmental legislation of the noise emissions in effect in the city.     

清末中英基督教堂建筑比较研究

随着国内中西建筑文化交流研究的拓展与深化,近代西方基督教会在华营建活动及其建筑渐为学术界所关注。通过对近代中国以及西方教会宗主国—英国（为例）同期教堂建筑样式进行对比,阐释近代中西建筑文化交融中错综复杂的建筑现象,揭示近代教堂建筑发展的特征、规律。     

基于极值相关性的超高层建筑风荷载组合研究

为研究不同长宽比超高层建筑三维风荷载组合,通过高频测力天平风洞试验得到了5种长宽比的矩形超高层建筑基底剪力、弯矩和扭矩时程。基于试验数据和计算结果,分析了三维风荷载效应的分布及其极值相关性。在此基础上,对比分析了不同长宽比的超高层建筑顺风向与横风向、顺风向与扭转向以及横风向与扭转向之间的风荷载效应极值分布规律和统计参数。最后,采用概率统计方法评估了不同长宽比对结构三维风荷载组合系数的影响,并给出了一组基于极值相关性分析的结构三维风荷载组合系数推荐值。结果表明：对于超高层建筑,虽然不同方向风荷载效应之间相关系数可能很低,但其三维风荷载效应极值相关性不可忽略;以横风向或扭转向为主方向进行组合时,其余方向同步比值存在明显的非高斯分布特性;对于不同长宽比超高层建筑,其极值相关性的差异会导致组合系数存在差别,在确定风荷载组合方法时,应考虑长宽比的影响。     

Thermal performance evaluation of domed roofs

Domed roofs have been used in Iran and many other countries to cover large buildings such as mosques, shrines, churches, schools. They have been also employed in other buildings like bazaars or market places in Iran due to their favorable thermal performance. The aim of this research is to study about domed roofs thermal performance in order to determine how they can be helpful in reducing the maximum air temperature of inside buildings during the warm seasons considering all parameters like air flow around them, solar radiation, radiation heat transfer with the sky and the ground as well as some openings on the building. The results of the study show that the thermal performance of the investigated domed roof is better than the building with flat roof, particularly when the dome is covered with glazed tiles. In addition to their aesthetic values, domes covered with glazed tiles have thermal benefits of keeping the inside air of these buildings relatively cool during the summer. Moreover, openings cause passive air flow inside building, which is helpful for human comfort.     

Die Raumakustik in Atrien

The room acoustics in atria This article describes the room acoustic features of atria. The work was forced by several inquiries of designers and architects concerning simplified methods to design the room acoustic in lobbies and atria in response to advanced acoustical requirements of atrium users. The described results of measurements in several atria proved that in most cases the room acoustical properties were not satisfied. Starting with acoustical features of concert halls, typical room acoustical behaviours of atria as well as limits in the acoustical properties were developed. Up to now the acoustic perception of speaking and music performances is strongly constricted in most atria.     

A comparison of occupant comfort and satisfaction between a green building and a conventional building

It has been argued that “green” buildings have a better indoor environmental quality (as measured by the comfort perceptions of occupants) than conventional buildings and that this translates into a more satisfying workplace for the building's occupants and, in turn, a more productive workforce. To test this we measured the comfort and satisfaction perceptions of the occupants of a green university building and two conventional university buildings with a questionnaire that asked occupants to rate their workplace environment in terms of aesthetics, serenity, lighting, acoustics, ventilation, temperature, humidity, and overall satisfaction. The university buildings at the centre of the study are located in Albury-Wodonga, in inland southeast Australia. The green building, which is naturally ventilated, is constructed from rammed earth and recycled materials. The conventional buildings have heating, ventilating, and air-conditioning (HVAC) systems and are of brick veneer construction. We found no evidence to believe that green buildings are more comfortable. Indeed, the only difference between the buildings was that occupants of the green building were more likely to perceive their work environment as warm, and occupants who felt warm were more likely to describe their work environment as poor. However, the hydronic cooling system of this building was malfunctioning at the time of the study and hence this result cannot be generalised as a difference between green buildings and conventional HVAC buildings. All other aspects of comfort, including aesthetics, serenity, lighting, ventilation, acoustics, and humidity, were not perceived differently by the occupants of the two types of building.     

音乐厅舞台声学设计解读——有利于演奏者的声学条件

舞台是厅堂的重要组成部分。早期的舞台声学设计侧重考虑改善观众席的声学环境,事实上,合理的舞台声学设计不仅可以改善观众厅的听闻环境,更可改善舞台本身的声学环境,创造出有利于演奏者的声学条件,演的高质量才可达到听闻的高质量。本文通过回顾厅堂舞台声学的实践与理论研究成果,解读有利于演奏者声学条件的舞台声学设计方法。     

A study of the daylighting performance and energy use in heavily obstructed residential buildings via computer simulation techniques

The quality and quantity of natural light entering a building depends on both internal and external factors. In Hong Kong, many buildings are high-rise blocks constructed close to each other and hence the external factor plays a significant role in daylighting designs. This paper studies the daylighting performance and energy use for residential flats facing large sky obstructions via computer simulations. Key building parameters affecting daylighting designs are presented. The daylighting performance for typical interior rooms was investigated in terms of illuminance level and daylight factor. The daylight levels of residential flats can be severely reduced by neighboring buildings and hence the externally reflected component would be the main source of natural light. The indoor daylight levels for kitchen and living/dining faced large neighboring building were found always less than the standard maintenance illuminance during daytime period. These imply that many residential flats in Hong Kong would have to rely on supplementary electric lighting.     

Modeling volatile organic compound (VOC) concentrations due to material emissions in a real residential unit. Part I: Methodology and a preliminary case study

High volatile organic compound (VOC) concentrations following building decoration have been observed frequently. In reality, however, residents do not know the indoor VOC concentration levels until the buildings are tested, which seldom provides a preventive measure. While several indoor air quality (IAQ) simulation programs have been developed to predict indoor contaminant levels, case studies in the literature are scarce regarding the predictability of indoor VOC concentrations as well as how such predictions could be performed in real buildings. In this paper, we intended to conduct a proof-of-concept study whether simulations can help to reveal some of the key features of VOC concentrations during indoor decoration process. We conducted a case study, simulated and measured the VOC concentrations of a residential unit during the room decoration process. Results show that while certain agreement was achieved between the measurement and simulation, application of IAQ models to real buildings is challenging under the best of circumstances—single zone spaces with very few emission materials inside.     

Use of artificial neural network to evaluate the vibration mitigation performance of geofoam-filled trenches

Development activities in a city often generate ground vibration that can cause discomfort to the occupants in nearby buildings, disturbances to the activities undertaken in the buildings and possible damage to nearby structures. This ground vibration is caused by construction activities such as pile driving, ground compaction etc., and road and rail traffic. The use of trenches has been an effective way to mitigate the adverse effects of such ground vibration. The effectiveness of the trench depends on many parameters including the properties of the vibration source, soil medium and trench in-fill material, trench dimensions and the requirements of the receiver. The process of selecting an effective trench for vibration mitigation can therefore become complex due to the influence of a number of parameters and their wide range of values. This paper investigates the use of artificial neural network (ANN) as a smart and efficient tool to predict the effectiveness of geofoam-filled trenches to mitigate ground vibration. Towards this end, a database is developed from an extensive study on the effects of the controlling parameters through numerical simulations with a validated finite element (FE) model. At a certain distance from the vibration source, a geofoam-filled trench is introduced to evaluate the efficiency of vibration mitigation with changes in key parameters such as excitation frequency, amplitude of load, trench configuration (i.e. depth and width), soil shear wave velocity, soil density and damping ratio. These were selected as the input parameters for the ANN while amplitude reduction ratio and peak particle velocity (PPV) were considered as outputs. A multilayer feed forward network was used and trained with the Levenberg-Marquardt algorithm. Neural networks with different configurations were evaluated by comparing coefficient of determination (R²) and mean square error (MSE). The optimum architecture was then used to predict previous results, which revealed the accuracy and the effectiveness of the ANN approach. The findings of this study will provide useful information for vibration mitigation using geofoam-filed trenches.     

北京地区浅埋暗挖法下穿施工既有隧道变形特点及预测

 城市地下工程建设中,新建隧道近距离下穿施工对既有隧道造成的扰动不可避免。正确分析及可靠预计既有隧道变形成为目前地下工程建设的热点问题。在预测隧道开挖引起的地表位移的经验法中,Peck公式最简便,应用也最为广泛。搜集北京地区10个近接下穿工程23组数据,对既有隧道实测变形进行拟合,发现绝大多数符合Peck公式分布规律。拟合得到地层损失率为0.116%～1.183%,沉降槽宽度系数为0.93～6.76。讨论新建隧道施工工法、辅助施工方法、新建隧道与既有隧道的埋深、既有隧道刚度、新建隧道双洞间距、变形缝位置等因素对经验参数的影响,给出经验参数的修正公式。将经验参数修正公式与Peck公式相结合,为北京地区受新建隧道下穿施工影响的既有隧道变形提供一个简便、快捷的预测方法,并通过工程实例验证了预测方法的有效性。研究成果可对未来北京同类工程和其他地区近接工程设计和施工提供参考,同时对丰富同类工程数据库具有重要意义。