PROBAMAT-21st Century: Probabilities and 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.

Klappentext

The materials dealt with in this volume include wood, concrete, various metals, composites, ceramics, and porous geological media. Obviously, the properties and serviceability of such materials vary widely, and an almost universal theme in their testing is that the properties depend on the scale at which the analysis or observation is made. At each scale, probability' plays an important role, where the wordprobability' is used in a wider sense than the classical one. br/ The book begins with a review of progress over recent years, identifying key questions that remain open. One point is how to observe/measure material properties at different scales, and whether a probabilistic approach, at each scale, is always applicable and advantageous. Obstacles to the identification of a universal approach include the wide range of materials and the diversity of applications. br/ The hierarchical nature of materials and implications for modelling, testing and application are discussed extensively. Modern mathematical tools show considerable promise in attacking the multiscale nature of materials in modelling and testing, such as wavelet analysis, intersection methods for random sets, and truncated series expansion of random fields. Multiscaling is also discussed in the context of nonlinear dynamics. Furthermore, the concepts of scaling and criticality and their applicability in materials science create interesting points of view. br/ Most contributions present both experimental and analytical/numerical results. A few are purely theoretical, and some are purely numerical.

Inhalt
I Contributions.- 1. Material structure, description and application.- Simultaneous failures in fiber bundles.- Synergetical models of fatigue-surface appearance in metals: the scale levels of self-organization, the rotation effects, and density of fracture energy.- Lacunarity of the contact domain between elastic bodies with rough boundaries Numerical analysis and scale effects.- How far can we control the heterogeneity of wood and wood based materials through design?.- Crack roughness.- Common characteristics of damage accumulation and fracture of solids.- 2. Scaling, fracture and applications.- Mechanical response of disordered media/patterns, measurements and modelling.- Failure scaling as multiscale instability in defect ensemble.- A statistical-probabilistic approach to microstructure-structure relations in failure and damage of ceramic composites.- Kinetic models of brittle crack growth: crack pattern statistics and longevity of solids.- From classic to fractal mechanics of disordered media: self-consistency versus self-similarity.- 3. Structures and structural components.- Probabilistic models of structures.- A new model for inter-fibre-failure of high-strenght uni-directionally reinforced plastics and its reliability implications.- Probabilistic approach to dimensioning of structures exposed to stochastic operating loads.- Modeling of material uncertainties using the nonlinear stochastic finite element method.- Structural approach in contimuun modeling of damageable particulate composites.- Finite element and reliability: combined methods by response surface.- Probabilistic design of performance in glued laminated timber.- 4. Numerics, simulation techniques and design processes.- Scale effect for concrete specimens: a numerical model.- Numericalmodelling of concrete elements of increasing size.- Multiscale material characterization and applications.- Probailistic aspects in shape memory alloy modelling Constitutive law for energy dissipators.- Homogenization of random granular media.- Towards quantitatively correct micromechanics models.- 5. Porous and granular media.- Multiscale permeability and dispersion in randomly heterogeneous geologic media.- Probabilistic modeling of granular media anisotropy.- A unique model for the sand and clay behavior.- A comparison between measured and calculated values in geotechnics An application to settlements.- Informational methods in optimization of tools.- 6. Fracture, fatigue.- Stochastic modeling of fatigue crack growth in metals.- Two plasticity models considering microinechanics of observed phenomena.- Statistical kinetics of fracture of heterogeneous solids.- Deterministic and stochastic aspects of strain localization in the fatigue of metals.- II Synthetic papers and round table discussions.- Scales!.- Introductory remarks to session C: structures and structural components.- About the use of probabilities in material response prediction and material design.- Natural materials and composites.- Crack growth and damage accumulation A review of five papers for PROBAMAT 21st CENTURY.- Round Tables.