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Summary: The objective of the present paper is to present a numerical study on the penetration performance of concrete targets with 2 different water contents. Numerical analysis has been performed by using the finite element code Abaqus/Explicit, in which a coupled elastoplastic damage model has been developed for saturated/unsaturated concrete under a wide range of confining pressures. The performance of proposed model has been firstly verified by simulating the triaxial compression tests and penetration tests realized with saturated/dry concretes. Comparisons of available experimental results and numerical simulations show that the proposed model is able to reproduce satisfactorily the mechanical behavior of saturated and dry concretes. A higher failure stress and a more important pores closing are generally obtained in dry concrete samples with respect to saturated ones. Furthermore, the main observed patterns of penetration test realized with saturated concrete targets are also satisfactorily simulated by the numerical results. Therefore, the proposed model is used to numerically predict the penetration performance of dry concrete target, and the penetration performance of dry/saturated concrete target is discussed. We observe that in dry concrete target, the penetration of projectile is strongly declined, and a smaller damage zone is created. The numerical predictions and discussions can help engineers to enhance their understandings on the influence of hydraulic conditions on structural vulnerability of concrete structures subjected to near‐field detonations or impacts. [ABSTRACT FROM AUTHOR]

To better understand the microstructure parameters controlling grain crushing and how the microstructure evolution influences the crushing characteristics of rockfill particles, the emphasis of the present study focuses on the size effects on the crushing strength of rockfill particles, with special attention to internal flaws. Single‐particle crushing tests are performed on rockfill particles with four different size fractions. By combining these results with the experimental results from the literature, the suitability of the Weibull model to describe the size effects on the breakage strength of rock grains is discussed. To understand why larger grains possess lower strength, a bonded particle model (BPM) is established in YADE to simulate the particle crushing tests. Model parameters are calibrated against the obtained force–displacement curve. The failure and deformation behaviors of studied rockfill particles are satisfactorily reproduced by the numerical simulation. The size effects are then studied using the agglomerates with different flaw characteristics (e.g., sizes, numbers, volume ratios, distributions, and locations). Numerical results exhibit that for the studied rockfill particles, when the ratio of flaw size to agglomerate size is less than 0.186, the flaw volume ratio is the key factor for size effects, and the breakage strength of particles is slightly related to the flaw size. In contrast, the breakage strength of particles depends not only on the flaw volume ratio but also on the flaw distribution/location when the flaw size is large. Microscopic analysis and DEM modeling can improve the understanding of crushing and deformation behaviors of rockfill particles. [ABSTRACT FROM AUTHOR]