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111.
青岛市区道路交通噪声及其控制对策研究   总被引:4,自引:0,他引:4  
本文介绍了青岛市区道路交通及其噪声特点,分析了构成青岛市区道路交通噪声的主要影响因素,指出必须在合理规划道路、科学效能管理的基础尖的降噪技术措施,才能确定达到控制道路交通噪声的目的。  相似文献   
112.
城市房屋基本数据库在城市综合防灾对策研究中是一个最基本的依据。它对于评估城市的抗灾能力,预测灾害损失是必不可少的,同时,数万栋房屋基本情况的调查又是一项工作量极大,费力耗时的工作。因此,必须事先对房屋数据库的生成作周密细致的总体安排,以取得事半功倍的效果。本文拟就汕头市房屋基本数据库要达到的目标,调查内容,实施方法以及数据库的特色等方面作一综合介绍。  相似文献   
113.
针对超高层建筑火灾探测器的优化布点问题,引入斯塔克尔伯格模型的思想,在不同长、宽空间结构内提出了一个更经济的布点方法--矩形、三角形优选法,并从布线难度、工程量及布线成本三个维度对矩形、三角形优选法进行了分析研究。  相似文献   
114.
Human factors play an indispensable role in process safety during fire risk process. Fire evacuation of underground comprehensive buildings is a critical consideration for practical importance. Here, evacuation experiments were conducted in the Guangzhou East Railway Station Plaza, a large underground comprehensive building in Guangdong, China, with the plaza occupants as the participants. The evacuation factors, namely evacuation time and evacuee-selected evacuation routes, were evaluated using empirical equations (the Togawa model and the Melinek and Booth model) and evacuation modelling software (EVACNET 4 and composite occupant evacuation model). The experimental data were used to verify the empirical equations and evacuation models and to modify specific empirical parameters. The effect on escape route judgement and selection under emergency situations was analysed. The results demonstrated that direct access to outdoor exits could considerably reduce evacuation time. The experimental N and ts were 1 person/m·s and 28 s, respectively. The total evacuation time was 281 s, and the EVACNET 4 and composite models’ simulations of safe evacuation were 285–290 s, which was consistent with the experimental data—validating the high accuracy and applicability of the models.  相似文献   
115.
Because of climatic reasons and of reduced concentrations of SO2, ground-level ozone (O3) is one of the main air pollutants in Southern Europe. Ozone levels are very high both in rural and urban locations. In the cities, O3 can affect human health and materials. Regarding materials, most relevant is the exposure to pollutants of cultural heritage buildings. In particular, monuments registered on UNESCO's list of the world heritage require special monitoring. In Italy 34% and 97% of the territory is exposed to corrosion risk higher than the tolerable level for limestone and copper, respectively. The tolerable corrosion level for limestone and copper was also exceeded in the central area of Milan. In this area the tolerable O3 concentration for copper was calculated. These concentrations (ranging between 30 and 40 μg/m3) cannot be exceeded at unchanged concentration of other pollutants to maintain corrosion levels below the tolerable ones.  相似文献   
116.
粉煤灰膏体充填是目前最为有效的建筑物下采煤技术,料浆运送是实现充填开采的重要环节。结合数学和弹塑性力学对粉煤灰膏体流变特性进行了理论推导,完成了实验研究,从粒径、比重、颗粒形状和膏体浓度等方面对输送机理进行探讨,结果可为粉煤灰膏体充填开采技术应用提供重要技术支撑。  相似文献   
117.
基于结构安全的高层建筑理论计算模型所确定的结构动力特性与实测值往往有较大差别,这会使结构动力响应的计算及风振舒适度的评价产生较大误差。针对此问题,基于风振舒适度评价的目的,考虑填充墙、楼板装饰面层、楼梯和活荷载取值四种精细化模型修正因素,提出了基于舒适度评价的高层建筑精细化计算模型的一般构建方法。通过实测和理论分析对某沿海高层建筑的精细化计算模型进行了研究,对精细化模型的修正因素进行了探讨。结果表明:精细化模型修正因素中填充墙对结构动力特性的影响最大,精细化计算模型的动力特性与实测值更吻合,更准确地反映了结构真实的振动特性。精细化计算模型的研究工作可为此类高层建筑的风振舒适度评价提供借鉴。  相似文献   
118.
BACKGROUND: Most historical buildings in Bordeaux city are made of limestone. This yellowish-white rock is rather porous and highly sensitive to pollution. As a consequence of local weathering conditions, these buildings present a dark appearance due to the development of a superficial dark grey to black crust. METHODS: For the last decade, a campaign has been underway to clean these buildings. Eleven techniques of surface treatment have been used, including laser beam technology. As a contribution to the study of laser beam effects on stone buildings, two analytical methods have been used on clean versus unclean surfaces: Cathodoluminescence (CL) and Electron Paramagnetic Resonance (EPR), in addition to SEM-EDX and XRD. RESULTS: The black crust is composed of different types of particles: carbon porous micro-particles of industrial origin, atmospheric dust due to the erosion of soils and rocks, alumino-silicate particles from urban pollution; all these particles being cemented by gypsum. DISCUSSION: As far as heritage conservation is concerned, the laser surface treatment not only preserves the original patina of the stone, but also leaves surface smoothness unaltered. CONCLUSIONS AND PERSPECTIVES: CL and EPR data confirm that lasers--with highly controlled parameters--only get rid of the black crust and, thus, reveal the underneath layer, the so-called patina. This patina shows no luminescence, whereas the limestone on which it has grown shows a bright orange emission of CL. This indicates CL to be a fast and easy way to provide a high quality control for the restoration of polluted ancient stones.  相似文献   
119.
既有建筑节能改造核心实施主体——ESCO市场行为直接影响既有建筑节能改造市场发展,分析了EPC模式下既有建筑节能改造ESCO市场行为的目标性、利他性、有限理性、环境适宜性等特征,揭示了EPC模式下ESCO行业规模扩张、发展趋于规范、市场细分多元化、服务业务整体化的行为演变规律,以期为既有建筑节能改造市场治理研究奠定分析...  相似文献   
120.
建筑物外墙清洗技术综述   总被引:1,自引:0,他引:1  
对于暴露在大气中的建筑物外墙进行定期的高效清洗,有利于保护建筑物、延长装饰周期、美化环境等.为了了解在建筑物外墙清洗技术领域中的进展,利用中国期刊全文数据库、维普中文科技期刊全文数据库和万方数据库, 对近10多年来我国在建筑物外墙清洗技术领域的研究成果进行了检索和分析, 在此基础上提出了发展我国清洗技术的一些观点.  相似文献   
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