ISSN:0003-8628    

DOI:10.1080/00038628.1999.9696871

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

On low-rise buildings the damage to and destructive removal of small roofing elements forming a porous roof membrane, such as tiles, shingles and shakes, is largely controlled by the heal mean andpeak wind speeds that exist just above the roof surface. Some typical high speed regions have been identified by the selective removal of cladding elements during high wind events [Refs. 1 and 2]. Frequently these high speed regions close to the roof surface are comer or ridge vortices. This study endeavours to map the mean surface wind speeds in the wind tunnel on some typical house geometries at a scale of 1:25 with a robust hot-probe anemometer. In one configuration these data were confirmed by full-scale measurements. Some peak wind-speed data were also collected at selected locations with a highly responsive hot-film anemometer. Both sloped and near-horizontal roofs have been investigated. In all geometries, a locally increased mean wind speed of up to sixty percent above the approach flow value was found for particular wind azimuths at critical locations on the roof surface. The peak gusts close to the roof surface varied significantly with the flow regime present, but a useful design gust factor of 2.5 times the approach mean velocity was found to be an upper bound for most roof-surface wind speeds.

ISSN:0003-8628    

DOI:10.1080/00038628.1999.9696872

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

To calculate dynamic solar heat gain in buildings, one must know solar optical properties, namely, incidence-angle-dependent solar-transmittance, absorptance and hence -reflectance of window systems. The properties may be estimated using procedures which use Fresnel equations and ray-tracing technique or matrix multiplication method. This paper presents a simple generalized procedure to estimate incidence-angle-dependent solar optical properties of clear, tinted and coated glass of any thickness. Knowing the solar optical property of a glass at normal incidence, incidence-angle-dependent solar optical property may be estimated from corresponding relative solar optical property. The estimated results for different window systems are compared with measured values of incidence-angle-dependent solar-transmittance and—absorptance and are discussed. It is observed that the calculated results are quite close to the corresponding measured ones (with maximum relative error of 11.18%) up to 70° incidence angle for various types of glazings considered. However, this relative error increases beyond this angle up to 80° and then starts decreasing.

ISSN:0003-8628    

DOI:10.1080/00038628.1999.9696873

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Various authors have documented classifications for structural timber joints. These represent different approaches according to the interest and professional background of the authors. This paper aims to set the knowledge accumulated through centuries from personal views and/or confined classifications into a more general order of a taxonomy.

ISSN:0003-8628    

DOI:10.1080/00038628.1999.9696874

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

This study investigated the change in glazing daylight transmittance due to the deposition of urban airborne pollutants using a seven-sided glazed building model in a large city centre. The model was constructed with four vertical surfaces, two surfaces inclined at approximately 45° and one horizontal surface in order to examine the effect of orientation and inclination on the rate of deposition. The model remained at the site for two consecutive annual runs. The main feature affecting the loss in glazing transmittance due to deposition was found to be extreme weather conditions, which in this context implies thunderstorms (heavy rains) and snow. Other meteorological factors, such as relative humidity and wind, also affected the deposition of airborne pollutants on the glazing, but to a lesser extent. The effect of seasonal changes was minimal. Glazing transmittance was seen to decrease (due to deposition of airborne pollutants) with the change in the angle of inclination of the glazing from the vertical to the horizontal.

ISSN:0003-8628    

DOI:10.1080/00038628.1999.9696875

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

To overcome the inconvenience of sunlight testing of building models with tripods and sundials (Robbins 1986), sunlight heliodons extended from the concept of Dufton and Beckett heliodon (Dufton & Beckett, 1931) have been developed. These developed heliodons include an earlier tailored-made light duty heliodon (Cheung 1996a), and a heavy duty heliodon assembled from commercially available precision machining tools (Cheung 1996d). This heavy duty heliodon is developed on the same principle as the earlier light duty me. This paper reports on the detailed construction and operation of this heavy duty heliodon.

ISSN:0003-8628    

DOI:10.1080/00038628.1999.9696876

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The reported study is based on the assumptions that intimacy is a concept that is interconnected with managing interactions within our social environment, and that different types of environmental contexts promote different levels of group intimacy and social interaction. To investigate these assumptions, the reported study tested the effect of both environmental structure (i.e., design and arrangement of interior space), and seating location (near entrance, next to window, in the middle and at the corner) on both group intimacy and social interaction. The study was conducted in two different eating environments (university student cafeteria, and an off campus restaurant), the customers of which, were mostly students. The results indicated the effect of environmental context on both group intimacy and social interaction. Moreover, results revealed a positive correlation between intimacy and social interaction, which was conditioned by the environmental context.

ISSN:0003-8628    

DOI:10.1080/00038628.1999.9696877

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The amount of daylight entering a building and its distribution depend an both interior and exterior factors. In Hong Kong, most buildings are built close to each other and hence the external environment plays a significant role in the daylighting designs. A study of the local and overseas Building Regulations indicates that the existing statutory documents in Hong Kong and Britain may not be conductive to effective daylighting. Key building parameters affecting daylighting performance in Hong Kong are presented. The quality and quantity of daylight for typical interior rooms have been assessed in terms of room depth, no-sky line and average daylight factor. It has been found that the daylight level of residential flats can be severely reduced due to neighbouring buildings. Without any sky obstruction, the average daylight factor ranges from 0.5% for kitchen to 3–5% for bedroom. Sky blockage would be critical for obstruction angles greater than 60°. These imply that many residential flats in Hong Kong would have to rely on supplementary electric lighting.

ISSN:0003-8628    

DOI:10.1080/00038628.1999.9696878

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:0003-8628    

DOI:10.1080/00038628.1999.9696879

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:0003-8628    

DOI:10.1080/00038628.1999.9696880

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor