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The permanent deformation after earthquakes is an important seismic safety performance indicator for rockfill dams. Based on dynamic triaxial tests, taking grading reduced coarse-grained materials as the test object, the influence of factors including density, particle grading, confining pressure, consolidation stress ratio, and number of vibration cycles on its residual deformation was discussed. On this basis, a numerical model in power function form was established for elaborating the earthquake permanent deformation for rockfill dams, an assumed homogeneous rockfill dam and a practical core rockfill dam were taken as research objects, respectively; by conducting nonlinear dynamic Finite Element (FE) analysis and combining with the single factor sensitivity analysis, the relationship between the main influence factors and dam permanent deformation was explored, which indicated that the influence of above factors on the permanent deformation of rockfill dams is consistent with the relationship between these factors and the residual deformation of coarse-grained materials in the triaxial tests. Finally, a fitting analysis method searching for the maximum permanent deformation of rockfill dams under different seismic intensities was proposed. Then corresponding suggestions were recommended from both design and construction aspects to improve the seismic resistance of super-high rockfill dams, which may have reference significance for similar projects.

A new concept for establishing the damage model for high concrete dams under earthquakes based on damage mechanics is presented in this paper. Unlike the conventional approach of considering the residual deformation by means of plastic-damage coupling, the proposed approach relates the degraded apparent elastic moduli of loading and unloading directly to the material experimental data. As such, the nonlinear analysis of the seismic response of dam-foundation systems is simplified and more reasonable, with no recourse to plastic-damage coupling. To verify the proposed approach of damage–rupture process for high concrete dams, the seismic behaviors of the Koyna gravity dam in India and the Shapai RCC arch dam in China both subjected to strong earthquakes were examined. It is demonstrated that the proposed approach can be reliably used to study the damage–rupture behavior of concrete dams under strong earthquakes.

An analysis of the dynamic response and damage assessment of partially confined metallic cylinders under transverse air-blast loading is presented in this paper. The examination of the blast shock wave load distribution and the consequences of standoff distances on the plastic deformation of cylinders was conducted with meticulous attention in the experimental testing. The charges of TNT were determined to have masses of 16.3 kg and 29.5 kg, while the distances at which they were placed from the target varied between 1.5 m and 4.25 m. Three unique deformation modes were found to exist in the unilaterally supported cylinder, all of which were directly connected to the distribution of the blast load. In order to obtain an improved understanding of the dynamic behaviors exhibited in cylinders, a finite element simulation model was utilized and subsequently validated using an examination of the experimental results. The assessment of shock wave damage was conducted by utilizing the residual deformation of the metallic cylinder as an equivalent characterization under lateral blast shock wave loading. The duration of the positive pressure zone of the shock wave was determined to be between one-fourth and ten times the vibration period of a unilaterally supported cylinder, indicating that the P-I (overpressure-impulse) criterion could be utilized for damage evaluation. The incorporation of the P-I criterion was subsequently employed to evaluate the detrimental consequences, taking into consideration the radial distribution of residual deformation identified in metal cylindrical shell constructions subjected to lateral blast shock wave loading. This research contributed to a better comprehension of the dynamic behavior of partially confined metallic cylinders subjected to lateral blast loading and highlights the significance of the P-I criterion for evaluating and mitigating the damage effects in such scenarios.

Through the dynamic triaxial tests of the tailings material taken from a copper mine, dynamic strength and residual deformation are studied. It is indicated that: the dynamic strength will increase with confining pressure and consolidation stress ratio. The related curves of dynamic shear stress ratio and vibration times have good normalization under different confining pressure. Whether isotropic or anisotropic consolidation, residual axial strain increase with confinng pressure, and the increasing trend are particularly obvious under anisotropic consolidation. The curve of residual axial strain and dynamic shear stress ratio is linear in the log-log coordinate, and the relation can be expressed by a power function.