Viscoelastic behavior of hybrid building materials

Abstract

The objective of this experimental work is the investigation of the viscoelastic behavior of a hybrid matrix, fiberreinforced building material. Hybrid matrix consisted of epoxy resin mixed with fine marble sand, whereas short steel fibers were used as reinforcement. The experimental procedure involved, first, the manufacturing of specimens using different hybrid matrix types and different reinforcement by weight ratios. Subsequently, bending relaxation experiments at room temperature were executed, under three-point bending test experimental configuration, at different strain levels and the variation of stress of the hybrid matrix material with time was monitored. The data obtained were used to (i) investigate the effect of reinforcement mass fraction contained in the composite on the viscoelastic behavior and (ii) to apply existed and newly developed viscoelastic models for the description of the observed viscoelastic behavior. More precisely, the four-parameter (Burgers) viscoelastic model and the modified Residual Property Model were calibrated and used to simulate the relaxation behavior of the materials manufactured and tested. Experimental results exhibited a clear influence of both reinforcement ratio and initial displacement on the viscoelastic behavior of the materials manufactured and tested, whereas the models proposed and used can adequately reproduce the variation of relaxation stress with time.

A comparative study between epoxy/Titania micro‐ and nanoparticulate composites thermal and mechanical behavior by means of particle–matrix interphase considerations

“…Property prediction model (PPM) is a semiempirical model developed by the first author and is used to predict the property variation with filler-volume fraction. It is the improved version of the modulus prediction model (MPM), already presented in previous works [59,60], after it was found by others that it can predict more material properties in addition to the elastic modulus [61]. The PPM model is described by the following equation:…”

“…where P c is the current property value of the composite, P f and P m is the filler and matrix property value respectively, k is the dispersion parameter and j the adhesion parameter. Finally, the filler volume fraction is denoted by V f. As it is explained in details [60], the model application is taking into account the fact that at low filler concentrations the composite behavior is mainly manifested by the filler-matrix adhesion and in a lesser extent by the filler dispersion, while at high filler volume fractions dispersion of the filler into the matrix is the most important parameter dictating the overall behaviour. Knowing only two experimental points, specifically one at a very low filler concentration and a second one at a high filler concentration, one can determine the parameters j and k. Then, through Eqs.…”

Elastic Electrically Conductive Composites Based on Vapor-Grown Carbon Fibers for Use in Sensors

“…Viscoelastic parameters from these models can be used to predict polymer creep deformation mechanisms. One of these models is the four-parameter model, known as the Burgers model, which can separate viscoelastic behavior into several components: an instantaneous elastic response, a retarded elastic response and a viscous response (Figure 4) [21][22][23].…”

Creep resistance of linear low density polyethylene/carbonaceous hybrid nanocomposites: Experiments and modeling

“…Additionally, in polymer composites, the creep response is strongly affected by polymer matrix/particle or fiber interaction. In a series of works [6][7][8][9][10][11] extended creep testing has been executed and analyzed by micromechanics modeling, on the basis of the viscoelastic feature of the matrix and its effect on the debonding mechanism of fiber reinforced polymers.Over the last decades, the thermomechanical performance of polymeric structure has been enhanced by the incorporation of nanosized fillers. The main nanofiller types entail silicon dioxide (SiO 2 nanoparticles, clays as nanolayers, and several types of carbonaceous nanofillers, such as carbon nanotubes (CNTs), carbon nanofibers (CNFs), and graphene nanoparticles.…”