A plasticity-fracture constitutive model is presented for prediction of the behavior of confined plain concrete. A three-parameter yield surface is used to define the elastic limit. Volumetric plastic strain is defined as hardening parameter, which together with a nonlinear plastic potential forms a non-associated flow rule. The use of non-associated flow rule improves the prediction of the dil...

Three different samples of Ti -6Al-4V of size 10mm diameter x15mm height compressed at a strain rate of 102 sec -1 in a 100KN servo hydraulic machine (DARTEC, UK make) with three different initial temperatures. First specimen of Ti-6Al-4V was compressed at an initial temp 1123K from initial length 15 mm to 10mm then the temperature was reduced to 1073K and compressed to a length of 7 mm now the...

In this study, the feasibility of predicting surface integrity and residual stresses by using elastoviscoplastic finite element simulations and temperature-dependent flow softening constitutive material modeling is investigated. A friction determination method is proposed to identify friction coefficients in presence of tool flank wear. Serrated and cyclical chip formation has been simulated fo...

Shear instabilities in the form of shear bands are often observed during high speed, plastic deformations of metals. According to one theory, their formation is attributed to eeective strain-softening response, which results, at high strain rates, as the net outcome of the innuence of thermal softening on the, normally, strain-hardening response of metals. In order to test the core instability ...

Strips of rabbit detrusor smooth muscle (DSM) exhibit adjustable passive stiffness characterized by strain softening: a loss of stiffness on stretch to a new length distinct from viscoelastic behavior. At the molecular level, strain softening appears to be caused by cross-link breakage and is essentially irreversible when DSM is maintained under passive conditions (i.e., when cross bridges are ...