Center for Concrete and Geomaterials, Northwestern University, Tech-241 0, Evanston, I L 60208 A recent nonlocal damage formulation, in which the spatially averaged quantity was the energy dissipated due to strain-softening, is extended to a more general form in which the strain remains local while any variable that controls strain-softening is nonlocal, In contrast to the original imbricate no...

An efficient formulation for dynamic analysis of planar Timoshenko’s beam with finite rotations is presented. Both an inertial frame and a rotating frame are introduced to simplify computational manipulation. The kinetic energy of the system is obtained by using the inertial frame so that it takes a quadratic uncoupled form. The rotating frame together with the small strain assumption is employ...

We introduce models for static and quasi-static damage in elastic materials, based on a strain threshold, and then investigate the relationship between these threshold models and the energy-based models introduced in [17] and [15]. A somewhat surprising result is that, while classical solutions for the energy models are also threshold solutions, this is not the case for nonclassical solutions, ...

optimal balancing is a new approach based on optimal control a which modes, controls and the amount of equilibrium scale are calculated simultaneously. this approach has a significant effect on increasing performance of industrial robots which causes maximum decreasing of energy consumption. despite many applications of robotics such as welding and gluing, the path is predefined , but other unk...

The structural evolution of Pb(Mg(1/3)Nb(2/3))O(3) (PMN) has been reviewed in terms of characteristic temperatures, length scales and timescales, with a view to considering the overall relaxor behaviour from the perspectives of strain and elasticity. A conventional analysis of lattice parameter data in terms of spontaneous strain and strain/order parameter coupling shows that even though a norm...

To characterize the thermomechanical response, especially the superelastic behavior of NiTi shape-memory alloys (SMAs) at various temperatures and strain rates, we have performed a series of both quasi-static and dynamic uniaxial compression tests on cylindrical samples, using an Instron servohydraulic testing machine and UCSD’s enhanced Hopkinson technique. Strain rates from 10 /s to about 420...

in this study, the turbulent kinetic energy redistribution process is investigated. to this aim, the direct numerical simulation (dns) of incompressible flow of a newtonian fluid through a channel at a shear reynolds number of reτ = 180 is used to produce a flow data base. then, these data are statistically analyzed. the turbulent kinetic energy redistribution is studied using the pressure-stra...

The need of polygonal elements to represent the domain is gaining interest among structural engineers. The objective is to perform static analysis and topology optimization of a given continuum domain using the rational fraction type shape functions of six node hexagonal elements. In this paper, the main focus is to perform the topology optimization of two-dimensional plate structures using Evo...