Aging-Induced Dynamics for Statically Indeterminate System

TL;DR

This paper reveals that statically indeterminate systems exhibit slow, aging-induced dynamics at the microscopic level, affecting their macroscopic behavior and allowing for simplified analytical solutions.

Contribution

It demonstrates the aging effect in statically indeterminate systems and introduces a heuristic method to determine saturated weight without detailed material properties.

Findings

Aging causes slow dynamics in indeterminate systems.

Microscopic contact evolution influences macroscopic behavior.

A simple analytical method for saturated weight is proposed.

Abstract

Statically indeterminate systems are experimentally demonstrated to be in fact dynamical at the microscopic scale. Take the classic ladder-wall problem, for instance. Depending on the Young's modulus of the wall, it may take up to twenty minutes before its weight saturates. This finding is shown to be shared by other statically indeterminate systems, such as a granule silo and a beam with three support points. We believe that the aging effect is responsible for this surprising phenomenon because it can be correlated with the evolution of microscopic contact area with the wall and floor. Finally, a heuristic and simple method is introduced that can uniquely determine and analytically solve the saturated weight without invoking detailed material properties.