Wind loads on a full-scale film-plastic clad greenhouse: With and without shelter from a windbreak

Abstract Full-scale measurements of the surface pressures on a sheltered and an unsheltered “tunnel” greenhouse were made in natural wind flow. The film-plastic cladding and curved arch construction were typical of single-span greenhouses found in the U.K. A windbreak of approximately 50% permeability was erected parallel to the building ridge for two spacings of 7.5 and 15 m between the building and the windbreak. At each location the windbreak was also raised to investigate the effect of a gap beneath it on the pressures acting on the film-plastic clad building. The pressure distributions for the sheltered and unsheltered greenhouse are compared and the relative merits of the various windbreak/building configurations are discussed. A shelter factor is proposed to be used in conjunction with the quasi-static procedures of the British Standards Institution Code of Practice, or codes of similar type, used for the assessment of design wind load.