Abstract. Mixed assumed stress finite elements for elastic-perfectly plastic materials require the solution of a Closest Point Projection (CPP) involving all element parameters integration constitutive equation. Here, dual decomposition strategy is adopted to split CPP at level into series CPPs points and in nonlinear system equations over element. The tested with four nodes mixed shell element...

Abstract—In this paper, a one-dimensional (1d) Parallel ElastoPlastic Model (PEPM), able to simulate the uniaxial dynamic behavior of seismic isolators having a continuously decreasing tangent stiffness with increasing displacement, is presented. The parallel modeling concept is applied to discretize the continuously decreasing tangent stiffness function, thus allowing to simulate the dynamic b...

in this research, softening and ratcheting behaviors of ck20 alloy steel cylindrical shells were studied under displacement-control and force-control cyclic axial loading and the behavior of hysteresis curves of specimens was also investigated. experimental tests were performed by a servo-hydraulic instron 8802 machine. the mechanical properties of specimens were determined according to astm e8...

This paper presents the development and experimental validation of a multizard bridge pier concept, i.e., a bridge pier system capable of providing an adequate level of protection against collapse under seismic and blast loading but not acting simultaneously . A multicolumn pier-bent with concrete-filled steel tube CFST columns is the proposed concept, and the adequacy of this system is experim...

[1] Oceanic lithosphere undergoes permanent deformation during subduction once the stresses exceed the elastic limit. Departures from elastic behavior occur by brittle failure in the shallow lithosphere and by a combination of lowand high-temperature creep at greater depths. We combine laboratory-based rheological models with estimates of slab shape from earthquake hypocenters to quantify the b...

A novel method to perform nanoscale mechanical characterization of highly deformable nanofibers has been developed. A microelectromechanical system (MEMS) test platform with an on-chip leaf-spring load cell that was tuned with the aid of a focused ion beam was built for fiber gripping and force measurement and it was actuated with an external piezoelectric transducer. Submicron scale tensile te...

In this paper, we investigate the effects of the non-singular stress (T stress) on the mode I near-tip fields lbr elastic perfectly plastic pressure-sensitive materials under plane-stress and small-scale yielding conditions. The T stress is the normal stress parallel to the crack faces. The yield criterion for pressure-sensitive materials is described by a linear combination of the effective st...

expansion equal channel angular extrusion (exp-ecae) is a severe plastic deformation (spd) operation for processing bulk materials. in the current study, aa7075 al was spd-processed by expansion equal channel angular extrusion (ex-ecae) at various temperatures and ram velocities. then, using split hopkinson pressure bar (shpb), the severely deformed products were compressed at room temperature ...

Plastic deformation in the form of slip lines is observed in front of notches in pure epoxy and robber-toughened epoxy specimens under four-point bending. In contrast to the case for pressure-insensitive materials, the angles between two families of slip lines emanating from notch surfaces are not 90°: they are smaller than 90 ° under tension, but they are larger than 90 ° under compression. Fo...

Strain localization is often a precursor to the ductile failure of materials. This paper investigates plastic strain phenomena in case random microstructures, namely cubic cells made an elastic-perfectly matrix embedding distribution identical non-overlapping spherical voids. The consideration microstructures allows for better representation interaction between voids and greater diversity modes...