Dynamic study of the behavior of a flexible material
Suez Environnement wanted to study the mechanical resistance of a new safety net system use to protect a technical zone against projectiles.
The aims of the service were:
- To verify that the elements used for the protective net are capable of absorbing the energy from the projectile (that the net is sufficiently deformed).
- To verify that the elements used for the protective net have the correct dimensions with regard to the dynamic forces generated by the projectiles.
- Potentially offer other ways to optimise or strengthen the system in case of non-compliance with the first two objectives.
The safety net is composed of fittings and cordage elements.
To bring the best solution to Suez Environnement, our company Calcul-Meca modelized the safety net and realized calculations in non-linear dynamic to check th faisability of the protection system and its resistance.
The modelization of the net and cordage use techniques of homogenization from the field of composite materials. In this way, the non-linear calcul can be performed with a orthotropic material.
Then, our experts in calculs have determined the velocity of the projectile based on the kinetic energy corresponding to the bursting of a pipe element.
Impact calculations on the net were performed in dynamic by direct integration using an implicit scheme. The stresses in the cordages could be detected during the phase of propagation of the wave.
The calculations obtained enabled MECA to submit an analysis and recommendations to Suez-Environnement.