Carbon nanotubes (CNTs) are principal constituents of nanocomposites and nano-systems. CNT size-dependent response assessment is therefore a topic current interest in Mechanics Advanced Materials Structures. CNTs modeled here by variationally consistent nonlocal strain gradient approach for Timoshenko nano-beams, extending the treatment [Int. J. Eng. Science 143 (2019) 73-91] confined to slender structures. Scale effects described integral convolutions, conveniently replaced with...

The nonlocal strain gradient theory of elasticity is the focus numerous studies in literature. Eringen's integral convolution and Lam's model are unified by a variational methodology which leads to well-posed structural problems technical interest. proposed Lam approach presented for functionally graded (FG) beams under torsion. Static dynamic responses shown be significantly affected size effects that assessed terms length parameters. Analytical elastic rotations natural frequencies...

The aim of this paper is to propose a fractional viscoelastic and viscoplastic model asphalt mixtures using experimental data several tests such as creep recovery performed at different temperatures stress levels. From best fitting procedure it shown that both the one curve follow power law model. It suitable for dashpot element arranged in series. proposed also available outside linear domain but case parameters depend on level.

A consistent nonlocal viscoelastic beam model is proposed in this paper. Specifically, a Timoshenko bending problem, where size- and time-dependent effects cannot be neglected, investigated. In order to inspect scale phenomena, stress-driven formulation used, whereas simulate effects, fractional linear viscoelasticity considered. These two approaches are adopted develop new model. Analytical solutions application samples of the presented. Moreover, show influences size on mechanical...

The simplest elasticity model of the foundation underlying a slender beam under flexure was conceived by Winkler, requiring local proportionality between soil reactions and deflection. Such an approach leads to well-posed elastostatic elastodynamic problems, but as highlighted Wieghardt, it provides elastic responses that are not technically significant for wide variety engineering applications. Thus, Winkler’s replaced Wieghardt himself assuming deflection is convolution integral reaction...

In this paper a novel method based on complex eigenanalysis in the state variables domain is proposed to uncouple set of rational order fractional differential equations governing dynamics multi-degree-of-freedom system. The traditional appropriately modified be applicable coupled equations. This done by expanding dimension problem and solving system variable domain. Examples applications are given pertaining systems under both deterministic stochastic loads.

Recently, a displacement-based nonlocal bar model has been developed. The is based on the assumption that forces can be modeled as viscoelastic (VE) long-range interactions mutually exerted by nonadjacent segments due to their relative motion; classical local stress resultants are also present in model. A finite element (FE) formulation with closed-form expressions of elastic and matrices obtained. Specifically, Caputo's fractional derivative used order interaction. static quasi-static...

Abstract The research of a formulation to model non-local interactions in the mechanical behavior matter is currently an open problem. In this context, strong based on fractional calculus provided paper. This derived from analogy with long-memory viscoelastic models. Specifically, same kind power-law time-dependent kernel used Boltzmann integral stress-strain relation as Fredholm relation. leads space Riesz and derivative order. For unbounded domain, proposed can be defined stress-...

The dynamic behaviour of micro- and nano-beams is investigated by the nonlocal continuum mechanics, a computationally convenient approach with respect to atomistic strategies. Specifically, size effects are modelled expressing elastic curvatures in terms integral mixture stress-driven local phases, which leads well-posed structural problems. Relevant equations motion slender beams formulated integrated an analytical approach. presented strategy applied simple case-problems nanotechnological...