Invited international contributions to this exciting new research field are included in this volume. It contains the specially selected papers from 45 key specialists given at the Symposium held under the auspices of the prestigious International Union of Theoretical and Applied Mechanics at Turin in October 1994.

This volume is a collection of the papers given at the workshop on Fracture Scaling, held at the University of Maryland, USA, 10-12 June 1999, under the sponsorship of the Office of Naval Research, Arlington, VA, USA. These papers can be grouped under five major themes: Micromechanical analysis Size effects in fiber composites Scaling and heterogeneity Computational aspects and nonlocal or gradient models Size effects in concrete, ice and soils . This workshop is the result of a significant research effort, supported by the Office of Naval Research, into the problems of scaling of fracture in fiber composites, and generally into the problems of scaling in solid mechanics. These problems, which are of interest for many materials, especially all quasibrittle materials, share similar characteristics. Thus, progress in the understanding of scaling problems for one material may help progress for another material. This makes it clear that a dialogue between researchers in various fields of mechanics is highly desirable and should be promoted. In view of this, this volume should be of interest to researchers and advanced graduate students in materials science, solid mechanics and civil engineering.

Fracture and Size Effect in Concrete and Other Quasibrittle Materials is the first in-depth text on the application of fracture mechanics to the analysis of failure in concrete structures. The book synthesizes a vast number of recent research results in the literature to provide a comprehensive treatment of the topic that does not give merely the facts - it provides true understanding. The many recent results on quasibrittle fracture and size effect, which were scattered throughout many periodicals, are compiled here in a single volume. This book presents a well-rounded discussion of the theory of size effect and scaling of failure loads in structures. The size effect, which is the most important practical manifestation of fracture behavior, has become a hot topic. It has gained prominence in current research on concrete and quasibrittle materials. The treatment of every subject in Fracture and Size Effect in Concrete and Other Quasibrittle Materials proceeds from simple to complex, from specialized to general, and is as concise as possible using the simplest level of mathematics necessary to treat the subject clearly and accurately. Whether you are an engineering student or a practicing engineer, this book provides you with a clear presentation, including full derivations and examples, from which you can gain real understanding of fracture and size effect in concrete and other quasibrittle materials.

There are numerous technological materials - such as metals, polymers, ceramics, concrete, and many others - that vary in properties and serviceability. However, the almost universal common theme to most real materials is that their properties depend on the scale at which the analysis or observation takes place and at each scale "probabilities" play an important role. Here the word "probabilities" is used in a wider than the classical sense. In order to increase the efficiency and serviceability of these materials, researchers from NATO, CP and other countries were brought together to exchange knowledge and develop avenues for progress and applications in the st 21 century. The workshop began by reviewing progress in the subject area over the past few years and by identifying key questions that remain open. One point was how to observe/measure material properties at different scales and whether a probabilistic approach, at each scale, was always applicable and advantageous. The wide range of materials, from wood to advanced metals and from concrete to complex advanced composites, and the diversity of applications, e.g. fatigue, fracture, deformation, etc., were recognized as "obstacles" in identifying a "universal" approach.

In this volume a survey of the most relevant nonlinear crack models is provided, with the purpose of analyzing the nonlinear mechanical effects occurring at the tip of macrocracks in quasi-brittle materials - such as concrete, rocks, ceramics, polymers, high-strength metallic alloys - and in brittle-matrix fibre-reinforced composites. Such local effects, as, for example, plastic deformation, yielding, strain-hardening, strain-softening, mechanical damage, matrix microcracking, aggregate debonding, fibre bridging, fibre slippage, crazing, and so on, are properly described through different simplified models, representing the peculiarities of the phenomena involved. The models are introduced and described separately and then compared in the last part of the book. This volume will be of interest to students, professionals and researchers in the field of nonlinear fracture mechanics.