Rigidity of hemispherical elastic gridshells under point load indentation

We present results from physical and numerical experiments on the rigidity of hemispherical gridshells under point load indentation. By systematically exploring the relevant parameters of the system, we provide a scaling law for the rigidity of elastic gridshells in terms of the dimension of the structure and the number of rods it contains, as well as the geometric and material properties of the individual rods. Our approach combines a set of precision desktop-scale experiments and discrete elastic rod simulations, which are found to be in excellent quantitative agreement. Our proposed empirical relation for the rigidity also points to the underlying nonlocal nature of the mechanical response of gridshells, in contrast to the local response of isotropic continuum shells. We further assess this nonlocality by quantifying the resulting radial displacement field as well as inspecting the effect of the location of the indentation point on the rigidity. (C) 2018 Elsevier Ltd. All rights reserved.