Treats odour penetration from garages etc. into connected room, caused by wind pressure on windward side openings. Discusses measures to prevent overpressure e.g. by a leeward side grill oran exhausting ventilator. Explains with mollier diagrams.
Reviews current status of research in North and South America relevant to the prediction of tall building behaviour in response to wind. Four main headings are considered a)meteorological research-wind structure and climate, b) full- scale investigations of wind action on tall buildings, c) development of wind tunnel techniques for building aerodynamics, d) simplified theoretical models of wind effects on tall buildings.
Presents some results not previously published of the full-scale loading project carried out at the post office tower, London. Autocorrelations and pressure spectra were determined for all the pressure transducers, and the variations of these around thestructure as well as vertically are discussed.
Reports results of surface wind pressure measurements made simultaneously at thirty-two points on a 57-storey office tower in Toronto. In addition to readings taken at half-second intervals during high winds, mean and root-mean square pressures were recorded for a five-minute interval once each hour, and pressure coefficients referred to the free stream dynamic pressure at 286 m were computed for comparision with wind tunneltest information.
Describes the philosophy and formulation of the simple and detailed procedures for wind loading of the Canadian National Building Code of 1970. Defines design pressure in terms of the exposure of the building, its response to gusts, the mean velocity pressure and the structural shape of the building. Compares predictions of dynamic drag response and cladding pressures with full scale measurements on several tall buildings. Concludes that the predictions of drag response and windward pressure are satisfactory. Discusses area requiring further definition.
Reviews wind research prior to 1958, which was based on the simple concept of a smooth air flow resulting in static design loads for most structures. States that research for the past ten years has benefited from three innovations. These are theimplementation of a statistical theory of turbulence, experimentation with turbulent boundary layers and the collection of full-scale measurements to identify and evaluate the real wind structure.
After a general introduction on the cause of wind, the dependence of wind speed increase with height on surface roughness and atmospheric stability is discussed. For the purpose of wind load calculation on structures this speed increase is often approximated by the pth power of height where the exponent p varies both with roughness, stability and the height of the layer in question. The last mentioned variation implies that extrapolations of p above its determination height cannot be depended upon.
States that to obtain accurate estimates of wind induced natural ventilation of buildings the pressure distribution over the building is required. Reviews the available information for isolated buildings and groups of buildings. Gives the results of wind tunnel measurements made on a cuboid when surrounded by buildings of the same shape. Results are presented statistically and indicate that the pressure distribution on a building can be fairly accurately determined provided the density of the built form and the roughness fetch are known.
Describes a research project undertaken at the Building Research Station to measure wind pressures on the G.P.O. tower, London, and dynamic strains in the tower shaft. The development of a suitable pressure transducer which used strain gauges as sensors is described, together with the installation at the tower. some othe problems of strain gauging large civil engineering structures are outlined. NOTE Final results of this project are given in "Wind pressure and strain measurements at the Post Office Tower" Newberry C.W. Eaton K.J. Mayne J.R. abstract no.229. B.R.E. C.P. 30/73
Full scale measurements were made of wind pressures on the 177m high post office tower, London. The variation of pressure with height was studied from recordings made at nine different levels between 49m and 168m above ground level. It is suggested that wind speeds of greater magnitude than those at the top of the tower sometimes occurred at lower levels.
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