In a preceding paper (Pampolini and Del Piero in JMech Mater Struct 3:969-981, 2008), the response of blocks made of a polymeric open-cell foam subject to uniaxial compression was analyzed. The hysteretic behavior exhibited in cyclic tests was interpreted within the context of nonlinear elasticity, as an effect of strain localization due to the non-convexity of the energy. Here we study some inelastic aspects of the response, such as rate dependence, strength decay after repeated loading, and memory effects. The analysis of some key experiments led us to the conclusion that viscous effects prevail over plasticity and damage. Consequently, we propose here a visco-elastic model, obtained by adding linear visco-elastic elements to our previous chain of nonlinear elastic springs. The paper is completed by the description of a series of experiments and of numerical simulations. © 2012 Springer-Verlag.
The influence of viscosity on the properties of open-cell polymeric foams in uniaxial compression: experiments and theoretical model
DEL PIERO, Gianpietro;PAMPOLINI, Giampiero
2012
Abstract
In a preceding paper (Pampolini and Del Piero in JMech Mater Struct 3:969-981, 2008), the response of blocks made of a polymeric open-cell foam subject to uniaxial compression was analyzed. The hysteretic behavior exhibited in cyclic tests was interpreted within the context of nonlinear elasticity, as an effect of strain localization due to the non-convexity of the energy. Here we study some inelastic aspects of the response, such as rate dependence, strength decay after repeated loading, and memory effects. The analysis of some key experiments led us to the conclusion that viscous effects prevail over plasticity and damage. Consequently, we propose here a visco-elastic model, obtained by adding linear visco-elastic elements to our previous chain of nonlinear elastic springs. The paper is completed by the description of a series of experiments and of numerical simulations. © 2012 Springer-Verlag.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
