Integrated structural design methodology for agricultural protecting structures covered with nets

The use of agricultural nets is increasing rapidly in a similar manner to the increase in greenhouse plastic covering materials. The expansion of nets in agriculture is expected to have a strong impact on the economy by improving the cost effectiveness of low-input agriculture. A methodology is proposed to support the design of new optimised net-supporting structural systems, fully exploiting the advantages offered by novel agricultural nets. The first step in the design procedure concerns the determination of loads and load combinations. The determination of wind loads, other actions and load combinations are briefly presented, based on a critical analysis and synthesis of available research results on the aerodynamic and airflow characteristics of nets and the special characteristics of the net-structural systems and on appropriate adaptation of relevant standards for design actions, when available. The design criteria on loads and load combinations are combined with the design criteria governing the analysis and design of nets and the functional design requirements. All design criteria are integrated into a methodology for the structural design of net-supporting structural systems. The proposed design methodology is expected to allow for the design of low cost optimised structures.

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