Design of a Large Dual – Structure Rainout Shelter1

Abstract

AbstractIn locations subject to rainfall during the cropping season, a rain excluding device must be employed to impose water stress for drought studies. A rainout shelter facility that covers 0.09 ha has been constructed for plant water stress research in central Texas. The shelter consists of twin structures connected to a single drive system and linking cable. The dual structures, which move together to cover the plot, incorporate permanent side and end walls thereby completely excluding driving rain. Minimum ground clearance of the wall allows some air movement under the closed shelter. Wind loading during shelter movement is neutralized as the structures move in opposite directions. The shelter is clad with fiberglass transmitting 70% of global radiation which allows continuing energy interception by the crop when the plots are covered. Movement of the building is controlled by a tipping bucket rain gauge, a local manual switch, and through telephone answering equipment connected electronically to the drive motor. The position of the building may be checked and changed by telephone. The sheltered area is large enough for replicated experiments with a satisfactory range of treatments. Several features have contributed to the successful operation of this shelter which is larger than any described previously.