Analysis and Design of Low-density Polyethylene Greenhouse Films

In the present paper, the mechanical behaviour of low-density polyethylene (LDPE) films under various combinations of pre-tension and uniform pressure schemes is investigated experimentally and numerically using the finite element method of analysis. The behaviour of the film is simulated by means of numerical models and with the material properties obtained in the laboratory by using standard testing methods. The finite element models used include both a commercial finite element program and a recently developed research non-linear finite shell element, capable of modelling membrane behaviour. The numerical analysis results obtained under appropriate boundary conditions and different analysis options are compared with experimental results obtained from a specifically designed experimental arrangement. For the cases tested experimentally, the two numerical approaches gave results in a good agreement with the experiment results, in the linear elastic region. Subsequently, using the research finite element model, design criteria are developed for the reliable design of LDPE greenhouse films.