Describes a covariance integration method for the determination of fluctuating overall structural loads due to wind and their effects on low rise buildings. The required aerodynamic information can be obtained from boundary-layer wind tunnel tests: static structural influence coefficients are also required. Themethod is an alternative to the direct on-line weighting technique, but is less demanding on wind tunnel instrumentation and data acquisition facilities. To obtain peak values, Gaussian probability distributions have been assumedfor the loads or their effects.
Gives a brief historical review of the development of wind engineering as a discipline. Discusses the simulation of wind loads on buildings, the development of boundary layer wind tunnels and problems in modelling the natural wind. Describes modelling of the aerolastic behaviour of buildings andof stack gas diffusion. Describes instrumentation and measurement techniques. Indicates areas requiring further development.
Describes a mechanically ventilated roof structure serving several different purposes. The proposed roof design consists of a hollow beam structure of concrete, insulation, air gap and finally an outer cladding layer of metal sheet or roofing felt. When the air handling equipment is in operation, an airflow is set up through the roof airgap and hollow beam structure, consisting either of external air alone, or of alternating external and exhaust air. This enables:<
Presents an evaluation of three proposals for the town plan for the Bulltofta district in Malmo in relation to the wind-induced energy losses. Analyses the wind statistics for the particular region and assesses the effects on energy consumption of winds from different directions. Evaluates the suitability of the various town plan proposals in relation to particular high energy loss inducing winds, making allowance for the overall exposure to sun and wind, the surface/volume ratio, building density and building heights.
Presents a review of the literature and a survey of the various types of window insulation systems and methods which are available, together with notes on experience of their use. The potentials of selective coatings on glass are discussed and comparisons between triple-glazed windows and window insulation are presented.< The survey serves as a feasability study for a larger project of which the object is to investigate the size of the savings which are possible with insulation of windows under varying conditions.
Reports an investigation of the effects of temperature differences, pressures, sun and wind conditions on a thermal image produced by thermography. This investigation is concerned mainly with measurement points associated with air leakage. Reports measurements on a single-storey timber-framed house under a pressure difference of 5,-2,-10 and -20 Pa.
Reviews existing models of air infiltration. Presents the basic formulations of the Institute of Gas Technology model. Outlines the data required by the model. Reports the refinement of the model by incorporating new subroutines. Describes testing of the model using data from IGT test homes, Princeton, Ohio and Canada. Comparison between model and test data shows that the model gives estimates of the rate of air infiltration with resonable accuracy.
Reports an experiment to assess the magnitude of air flow through the brickwork of one of the ECRC test houses. Describes apparatus and method and gives results. Also describes smoke and tracer gas tests to detect air flow within the wall structure. Concludes that under average wind pressures ventilation through the wall is negligible but that air from outside may penetrate the building envelope and extract heat from the house without contributing to the ventilation. This heat loss could be as much as 50 to 100 Watts per day.
Describes further experiments from the wind tunnel simulation of wind pressures on the Aylesbury housing estate. These experiments are not concerned with the acquisition of further data, but are designed to examine the validity of measurements.< Discusses the effect of varying observation and averaging times. Reports results of experiments, varying these times, but finds no observable trends in the dispersion results.
Reports root mean square and extreme pressure measurements made on a model of the Aylesbury housing estate in the Oxford wind tunnel. Also presents a complete set of measurements on the test house alone, corresponding to the varied roof pitch records. Presents extreme value data in the form of a Fisher-Tippett type probability function.< Discusses design of the experiments, experimental procedures and results. Gives 47 tables comparing full scale with wind tunnel results. Includes results of wind tunnel measurements made at Bristol University.
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