Tensile properties for netting materials used in aquaculture net cages

In order to perform a strength analysis of a net cage, it is crucial to know the tensile stiffness properties of the netting material. A new method for testing was established in order to determine the tensile properties of knotless netting materials. We applied it to a variety of netting materials and developed stress-strain relations. The stiffness was expressed as a constant value for relatively small strains, while for large strains the stress-strain relation was defined by a third degree polynomial. The average value of the constant stiffness for the tested wet netting materials was 81 N mm−2 with a standard deviation of 9 N mm−2 for strains less than 10%. For netting materials treated with anti-fouling paint, the average constant stiffness value was 131 N mm−2 with a standard deviation of 13 N mm−2 for strains less than 30%. The results are valid for uniaxial static loading of netting.