Bi-linear energy dissipating and shock absorbing device for cable subjected to tension

A method for configuring an energy dissipating device, comprising:

• providing a cylindrical shell;
• providing a first spring encased inside the cylindrical shell;
• providing a second spring encased inside the cylindrical shell;
• placing a separator in the cylindrical shell separating the first and second springs;
• providing a first end plate on a first side of the separator and a second end plate on a second side of the separator;
• providing a first rod and a second rod passing openings provided at each end of the cylindrical shell, with the first rod connected to the first end plate and the second rod connected to the second end plate;
• and
• placing a spacer inserted between the first end plate and the first spring, wherein the first spring has a smaller stiffness and the second spring has a larger stiffness, wherein the ratio of the smaller stiffness and the larger stiffness is approximately 0.05-0.2.

A system, comprising:

• a net;
• two posts spaced apart;
• horizontal cables hanging the net to the two posts with each end of the horizontal cable connected to a post;
• retaining cables with one end connected to the post and the other end connected to ground;
• and
• at least one energy dissipating devices installed on the retaining cables, the energy dissipating device including:
• a cylindrical shell;
• a first spring encased inside the cylindrical shell;
• a second spring encased inside the cylindrical shell;
• a separator in the cylindrical shell separating the first and second springs;
• a first end plate on a first side of the separator and a second end plate on a second side of the separator;
• a first rod and a second rod passing openings provided at each end of the cylindrical shell, with the first rod connected to the first end plate and the second rod connected to the second end plate;
• and
• a spacer inserted between the first end plate and the first spring, wherein the first spring has a smaller stiffness and the second spring has a larger stiffness, wherein the ratio of the smaller stiffness and the larger stiffness is approximately 0.05-0.2.