A new elasto-plastic constitutive model for jointed rock mass, which can consider the persistence ratio in different visual angle and anisotropic increase of plastic strain, is proposed. The proposed the yield strength criterion, which is anisotropic, is not only related to friction angle and cohesion of jointed rock masses at the visual angle but also related to the intersection angle between ...

Combined high pressure phase transformations (PTs) and plastic flow in a sample within a gasket compressed in diamond anvil cell (DAC) are studied for the first time using finite element method. The key point is that phase transformations are modelled as strain-induced, which involves a completely different kinetic description than for traditional pressure-induced PTs. The model takes into acco...

Transformation induced plasticity (TRIP) assisted steels contain a small quantity of carbon enriched retained austenite, which transforms into martensite during the course of plastic deformation. Transformation of this kind can be induced by both stress and plastic strain. The detailed mechanism by which the martensite is induced is different for these two scenarios. An attempt is made here to ...

This report presents a formal approach for optimizing the shape of freely supported isotropic plates to withstand air blast loading. Unique difficulties are presented by the nature of shortduration dynamic loading, viz. transient dynamic response, monitoring of maximum plastic strain failure at every point in the panel over time, optimizers that can handle non-differentiable, nonconvex and comp...

A line integral is exhibited which has the same value for all paths surrounding the tip of a notch in the two-dimensional strain field of an elastic or deformation-type elastic-plastic material. Appropriate integration path' choices serye bOlh to relate Ihe integral to the near tip deformatiot~s and, in many cases. to permit its direct e:tlalutllion. This (l.t'eraged measure of the near tip fie...

Indentation hardness has been used extensively for material characterization and many recent computational studies have established quantitative relationships between elasto-plastic mechanical properties and the response in instrumented indentation. In contrast, very few studies have systematically quantified the effect of the plastic deformation characteristics on the frictional sliding respon...

A procedure for efficient three-dimensional nonlinear time-history analysis of steel framed buildings is derived. It incorporates two types of nonlinear beam elements—the plastic hinge type and the elastofiber type—and nonlinear panel zone elements to model yielding and strain-hardening in moment-frames. Floors and roofs of buildings are modeled using 4-node elastic diaphragm elements. The proc...

Production of lightweight metals with a higher strength to weight ratio is always the main goal of researchers. In this article, equal channel multi angular pressing (ECMAP) process as one of the most appealing severe plastic deformation (SPD) methods on production of ultra-fine grained (UFG) materials studied. Two main routes A and C investigated by FEM and compared with each other from differ...

S U M M A R Y A number of field observations suggest that sliding on fault planes may occur at very shallow dip in the brittle field. The existence of active low angle normal faults is much debated because (1) the classical theory of fault mechanics implies that faults are locked when the dip is less than 30 and (2) shallow dipping fault planes do not produce large earthquakes (M > 5.5). To rec...

Current studies on the fatigue lifetime of ceramics are mostly focused on the relation between the stress amplitude (or maximum stress) and cycles to failure. For a more compliant and plastic ceramic which has a pronounced nonlinear stress-strain relation, the role of plastic strain in the fatigue damage is investigated for the first time in this study using a 12 mol% Ce-TZP. By testing at diff...