Why old tires are still being preferred as dock bumpers in harbours

TL;DR

This paper investigates why old tires are still widely used as dock bumpers, analyzing their mechanical properties and energy absorption capabilities to understand their effectiveness in maritime docking safety.

Contribution

It provides a detailed mechanical analysis of old tires as dock bumpers, highlighting the features that make them effective and informing future bumper design.

Findings

Reaction force is due to elastic deformation of the tread

Most energy absorption occurs after tread buckling

Tires' mechanical properties explain their effectiveness as bumpers

Abstract

The usage of old tires as dock and tugboat bumpers has been a common practice from long ago, proving to be safe for docking even the largest freighters. The reaction force and stored energy of an axially compressed tire is studied in order to determine the specific features of these variables that make tires so adequate as docking protections. The reaction force is attributed to the elastic deformation of the tread, which is modeled as a not too thin cylindrical shell. Most energy absorption takes place after tread buckling, which bends tread and increases its circumference, inducing strong tensile forces that contribute to stabilize the buckled structure. Results shed light on the mechanical properties that a designed dock bumper should exhibit.