In this book a systematic discussion of crack problems in elastic-plastic materials is presented. The state of the art in fracture mechanics research and assessment of cracks is documented, with the help of analytic, asymptotic methods as well as finite element computations. After a brief introduction to fracture mechanics, the two-parameter concept for stationary cracks is studied in addition to the issues in three-dimensional crack fields under coupling with strong out-of-plane effects. Cracks along interfaces and crack growth problems under mixed mode conditions are also treated. A systematic study of stress singularities for different notches is accompanied by detailed finite element computations.

This volume constitutes the Proceedings of the IUTAM Symposium on 'Nonlinear Analysis of Fracture', held in Cambridge from 3rd to 7th Septem ber 1995. Its objective was to assess and place on record the current state of understanding of this important class of phenomena, from the standpoints of mathematics, materials science, physics and engineering. All fracture phenomena are nonlinear; the reason for inclusion of this qualification in the title was to reflect the intention that emphasis should be placed on distinctive aspects of nonlinearity, not only with regard to material consti tutive behaviour but also with regard to insights gained, particularly from the mathematics and physics communities, during the recent dramatic ad vances in understanding of nonlinear systems in general. The expertise represented in the Symposium was accordingly very wide, and many of the world's greatest authorities in their respective fields participated. The Symposium remained focussed on issues of practical significance for fracture phenomena, with concentration on aspects that are still im perfectly understood. The most significant unifying issue in this regard is that of scale: this theme was addressed from several perspectives. One important aspect is the problem of passing information on one scale up or down, as an input for analysis at another scale. Although this is not always the case, it may be that the microscopic process of fracture is understood in some particular class of materials.

My wife Tatyana, daughter Mariya, son Alexandr It is well known that the mixed-mode conditions appear when the direction of the applied loading does not coincide with the orthogonal K,-Kn-Km space. In general, in the industrial practice the mixed-mode fracture and the mixed-mode crack growth are more likely to be considered the rule than the exception. Miller et al. considers that cracks can grow due to a mixture of processes (ductile and brittle), mechanisms (static, fatigue, creep) and loading modes (tension, torsion, biax ial/multiaxial). Additionally mixed-mode crack-extension can be affected by many other considerations such as artifact geometry (thin plates, thick shells, and the size, shape and orientation of the defect), environmental effects (temperature, gaseous and liquid surroundings), material state (crystallographic structure, heat treatment and route of manufacture) and stress conditions (out-of-phase and ran dom loading effects). The main feature of the mixed-mode fracture is that the crack growth would no longer take place in a self-similar manner and does not follow a universal trajec tory that is it will grow on a curvilinear path. There are various fracture criteria, which predict the behavior of cracks in brittle and ductile materials loaded in combined modes. Linear elastic fracture mechanics (LEFM) criteria predict basi cally the same direction for crack propagation. Cracks in brittle materials have been shown to propagate normal to the maximum tangential stress. In ductile ma terials yielding occurs at the crack tip and LEFM is no longer applicable.

Covering the whole of Asia and the Pacific region, this text provides both an analytic overview and specific data for each of the 60 countries. Introductory chapters cover regional issues, including: a regional review with the year's trends, developments and key events' analysis of the threat of terrorism in the region; the effects of deflation on the economy; the water crisis and its impact on the poor; and the successes and failures of micro-credit in the region.

From a leading expert in fracture mechanics, this text provides new approaches and new applications to advance the understanding of crack formation and propagation.