Shakedown and ratchetting under tension–torsion loadings: analysis and experiments

Abstract

SUMMARYStructural design analyses are conducted with the aim of verifying the exclusion of ratchetting. To this end it is important to make a clear distinction between the shakedown range and the ratchetting range. The performed experiment comprised a hollow tension specimen which was subjected to alternating axial forces, superimposed with constant moments. First, a series of uniaxial tests has been carried out in order to calibrate a bounded kinematic hardening rule. The load parameters have been selected on the basis of previous shakedown analyses with the PERMAS code using a kinematic hardening material model. It is shown that this shakedown analysis gives reasonable agreement between the experimental and the numerical results. A linear and a nonlinear kinematic hardening model of two-surface plasticity are compared in material shakedown analysis.

Ambient multiaxial creep: shakedown analysis of structures using stereo digital image correlation

“…One reason for this is the lack of full-field cyclic displacement and strain information that will convince designers to adopt shakedown criteria as a safe-state beyond first-yield, which is the focus of this article. Notable exceptions where shakedown designs are utilized include: vessels for demilitarization of munitions [8,9], tribology [10][11][12], multilayer semiconductor devices [13], pavement design [14,15], shape memory alloy components [16,17], and nuclear pressure vessels [1][2][3][4][18][19][20][21][22].…”

“…limited or unbounded strain accumulation) under axial torsional loadings. A similar experimental approach to Heitzer et al [18] is followed with the addition of full-field measurements. The authors Heitzer et al used an INSTRON 1343 test rig to subject hollow cylindrical ferritic steel samples (commonly used in the nuclear industry) to cyclic tension with nonzero mean stress and constant torque under ambient conditions.…”

“…The authors Heitzer et al used an INSTRON 1343 test rig to subject hollow cylindrical ferritic steel samples (commonly used in the nuclear industry) to cyclic tension with nonzero mean stress and constant torque under ambient conditions. In Heitzer et al [18], the thickness of the cylinder was choosen in order to induce a shear stress distribution through the hollow tube wall and create structural effects. In this paper, to increase the structural effect, solid specimens are used.…”

Prediction of asymmetric cyclic‐plastic behaviour for cyclically stable non‐ferrous materials

“…The considered non‐ferrous materials depict CS behaviour like that for the CS ferrous materials in strain‐controlled cycling, but in contrast, these materials exhibit shakedown phenomena at low stress levels unlike that observed for the CS ferrous materials in stress‐controlled cycling. Commonly, materials with different microstructures under asymmetric cyclic loading exhibit an increase in ratcheting strain (in stress‐controlled cycling) with increase in the number of cycles, but the rate of ratcheting appears to stabilize. The phenomenon of shakedown is a specialized case of ratcheting phenomena, where growth in the ratcheting strain is not observed after a few cycles, and the ratcheting rate is almost zero .…”

“…Simulation of the shakedown phenomenon considering combined hardening models typically demands the use of linear hardening rule in the KH component . But the earlier investigators have dealt with this problem by incorporating a small amount of nonlinearity in the third backstress of the KH component in the original Chaboche model to achieve simulations for the stabilized rate of ratcheting.…”