An Analysis of the Restitution Behavior of Strings Considering Mechanical Properties in Diametral Direction

Abstract

The restitution behavior of fiber strings was analyzed with considering the tensile and compressive properties. An impact test device in which the strings were tensioned and struck with a hammer was used and the impact speed and restitution coefficients were measured. A special string which the contact part was covered by a steel pipe was also used to examine the effect of diametral compressive deformation of strings. In ordinary test, the coefficient becomes small with increase of impact speed, while that becomes slightly large in the covered string test. Accordingly, this phenomenon is caused mainly by the compressive deformation. A dynamic restitution model considering diametral viscoelasticity of materials was suggested with approximating it by Voigt model. The restitution behavior was simulated by numerical computation. The calculation results showed good agreement with the experimental ones. © 1999, The Japan Society of Mechanical Engineers. All rights reserved.