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Reliability-based analysis and design of quasibrittle structures
Many engineering structures are composed of brittle heterogeneous (quasibrittle) materials, which include concrete, composites, rock masses, and masonry. Quasibrittle structures exhibit an intricate size effect on the overall failure behavior. This effect is now examined from a probabilistic viewpoint. Focus is placed on the structures that fail at the macrocrack initiation from
one material volume element, whose size is related to the size of material inhomogeneities. Based on a finite weakest-link model, the probability distribution of structural strength is shown to depend strongly on the structure size. Such size dependence has important consequences for reliability-based design. For example, the analysis of the failure of the Malpasset dam demonstrated that the direct extrapolation of laboratory- scale test results to full-scale design without considering the size effect would cause the structural failure risk to exceed the tolerable level by orders of magnitude. [82,83]