Characterisation of OSB properties for application in gridshells

In order to establish the viability and efficiency of orientated strand board (OSB) for use in bending active gridshells, the relevant material properties need to be established. Standard test methods for OSB assume the material will be used in large panel form. However, gridshells are made from long, relatively narrow and thin strips. To characterize the material properties of OSB for use in bending active gridshells, bending, torsion and compression tests were carried out to determine material strength and material stiffness properties. Test methods different to those in the standards were developed. Relatively high variations were observed in the material properties compared to those given in the standards. In addition, relatively high variations in product thickness were also observed in OSB sections. The variation in material and section properties identified should be considered when formulating design rules. This study shows that, in addition to a thorough understanding of the overall structural behaviour, in order to use OSB in bending active gridshells, application-specific material tests need to be carried out.