Nonlocal Stress Field Research Articles

Nonlocal interaction of a dislocation with a crack

Based on the classical stress analysis, the stress field of a screw dislocation near a semi-infinite crack is investigated by a conformal mapping method. The classical image force on the dislocation due to the crack is presented by the obtained classical image stress. To eliminate the singularity of the stress field at the crack tip, the nonlocal elasticity theory is adopted. A maximum of the image stress is found near the crack tip and the nonlocal image force is then acquired by the obtained nonlocal stress field. Both the stress and the image force show much difference from the classical ones and seem to be more reasonable physically.

A nonlocal theory for brittle fracture

In this paper, a nonlocal theory of fracture for brittle materials has been systematically developed, which is composed of the nonlocal elastic stress fields of Griffith cracks of mode-I, II and III, the asymptotic forms of the stress fields at the neighborhood of the crack tips, and the maximum tensile stress criterion for brittle fracture. As an application of the theory, the fracture criteria of cracks of mode-I, II, III and mixed mode I–II, I–III are given in detail and compared with some experimental data and the theoretical results of minimum strain energy density factor.

Antiplane eigenstrain problem of a circular inclusion in nonlocal elasticity

The antiplane eigenstrain problem of a circular inclusion is investigated in nonlocal elasticity. The nonlocals tress fields are obtained analytically by generalizing the classical line force concept to the case of nonlocal elasticity. The nonlocal effects, stress concentration and nonlocal surface residual, are exhibited for the first time.

A Line-force loading on the surface of a nonlocal elastic half-infinite medium

Transmission of a concentrated force into a half-infinite nonlocal elastic medium is examined. A nonlocal concentrated force boundary condition which is different from that of Nowinski is derived from the nonlocal principle. The nonlocal stress field is obtained analytically. The result eliminates the stress singularity which occurs in the classical stresses and also the nonlocal stresses derived by Nowinski. A theoretical cut-off strength Pc is discussed.