Triboelectrification of nanocomposites using identical polymer matrixes with different concentrations of nanoparticle fillers
In this study, we investigate triboelectrification in polymer-based nanocomposites using identical polymer matrixes containing different concentrations of nanoparticles (NPs). The triboelectric surface charge density on polymer layers increased as the difference in nanoparticle filler concentration between the two triboelectric layers escalated, despite the fact that the polymer matrix was the same in both layers. This effect was observed in tests of various polymer types and filler NPs. Our mechanical experiments and finite element analysis simulations confirmed that polymeric triboelectrification is related to the surface viscoelastic deformation that occurs during mechanical contact and …
Finite element modelling of slipage between FRP rebar and concrete in pull-out test
The paper presents numerical results of direct pull-out test of glass fiber-reinforced polymer (GFRP) rebars embedded in concrete. Rebars of three different cross-sections are considered: circular without longitudinal ribs and with two and four ribs. The design analyses of the rebar configurations embedded in concrete are investigated by the 3D finite element method (FEM), which takes into account the non-linearity using ANSYS software. The results of the numerical model with two ribs were compared with the experimental results. Then, the effect of different rebar geometries to the load-slip pull-out curves was studied. It is concluded that the influence of rib height and width on the pull-…