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It is essential to obtain shear modulus reduction and damping ratio curves to perform dynamic analyses of earth-cored embankment dams. Many studies have been performed for dynamic properties of clayey soils, but they have been limited for earth core materials of dams. This study conducted resonant column tests to obtain shear modulus reduction (G/[G.sub.max]) and damping ratio (D) curves for 31 specimens (17 undisturbed and 14 remolded specimens) from 13 earth-cored embankment dams. Empirical G/[G.sub.max] and D curves are proposed for dynamic properties of clayey earth core materials. Fitting curves are provided by using the functional forms of the Ramberg-Osgood and Darendeli models. The observation shows that the undisturbed earth cores yield relatively higher G/[G.sub.max] and lower D curves than the remolded cores. G/[G.sub.max] curves of compacted earth cores are relatively higher than those of Vucetic and Dobry curves for a similar level of plasticity index. Uncertainty and bias are calculated by performing residual analysis, which shows that there is no clear bias in predicting G/[G.sub.max] and the uncertainties between undisturbed earth core materials and natural deposits are at a similar level. A proposed empirical relationship of G/[G.sub.max] and D curves for earth core materials can be utilized for dynamic analyses of embankment dams for cases where there is insufficient in situ data.Key words: modulus reduction, damping ratio, earth core, resonant column, dynamic analysis, embankment dam.Il est essentiel d'obtenir des courbes de reduction du module de cisaillement et d'amortissement pour effectuer des analyses dynamiques des barrages en remblai a noyau en terre. De nombreuses etudes ont ete realisees sur les proprietes dynamiques des sols argileux, mais elles ont ete limitees aux materiaux de noyau de la terre des barrages. Cette etude a compris la realisation des tests de colonne de resonance pour obtenir des courbes de rapport de reduction de module de cisaillement (G/[G.sub.max]) et d'amortissement (D) pour 31 specimens (17 specimens non perturbes et 14 remanies) de 13 barrages en remblai a noyau en terre. Des courbes G/[G.sub.max] et D empiriques sont proposees pour les proprietes dynamiques des materiaux de noyau de terre argileuse. Les courbes d'ajustement sont facilitees par le biais des formes fonctionnelles des modeles Ramberg-Osgood et Darendeli. L'observation montre que les noyaux de terre non perturbes donnent des courbes G/[G.sub.max] relativement plus elevees et des courbes D plus faibles que les noyaux remoules. Les courbes des noyaux de terre compactes G/[G.sub.max] sont relativement plus elevees que les courbes de Vucetic et Dobry pour un indice de plasticite similaire. L'incertitude et le biais sont calcules au moyen d'une analyse residuelle, ce qui montre qu'il n'y a pas de biais clair dans la prediction de G/[G.sub.max] et les incertitudes entre les materiaux du noyau de terre non perturbee et les depots naturels sont dans un degre similaire. Une relation empirique proposee des courbes G/[G.sub.max] et D pour les materiaux de noyau de terre peuvent etre utilises pour des analyses dynamiques de barrages en remblai en cas de manque de donnees in situ. [Traduit par la Redaction]Mots-cles : reduction du module, rapport d'amortissement, noyau de terre, colonne resonnante, analyse dynamique, barrage en remblai., 1. IntroductionShear modulus reduction (G/[G.sub.max]) and damping ratio (D) curves are essential to perform dynamic analyses of earth-cored embankment dams (Gazetas and Dakoulas 1992). Earth core materials are mostly classified [...]

This paper presents an innovative digital twin dam and watershed management platform, K-Twin SJ, that utilizes real-time data and simulation models to support decision-making for flood response and water resource management. The platform includes a GIS-based geospatial digital twin of the entire Sumjin dam and river water system in Korea, with high-precision geospatial topography and facility information for dams and rivers (watershed area 4913 km2, river length 173 km, and 91 water infrastructures). The platform synchronizes real-time data such as rainfall, dam and river water levels, flow rate, and closed-circuit television (CCTV), and incorporates three hydraulic and hydrological simulation models for efficient dam operation considering the river conditions. AI technology is also used to predict the river water level and suggest optimal dam discharge scenarios. Additionally, the platform includes a geotechnical safety evaluation module for river levees, advanced drone monitoring for dams and rivers, and an AI CCTV video surveillance function. The digital-twin-based platform supports efficient decision-making for smart flood responses and contributes to reducing flooding damage and optimal operation through better smart water management. [ABSTRACT FROM AUTHOR]

In a seismic hazard analysis (SHA), the earthquake loading level should be predicted for one or more ground motion intensity measures (IMs) that are expected to relate well with the engineering demand parameters (EDPs) of the site. In this study, the goal was to determine the IMs that best relate to embankment dam deformations based on nonlinear deformation analysis (NDA) results of two embankment dams with a large suite of recorded ground motions. The measure utilized to determine the "best" IM was standard deviation in the engineering demand parameter (e.g., deformation) for a given IM, also termed "efficiency." Results of the study demonstrated that for the NDA model used, Arias intensity (AI) was found to be the most efficient predictor of embankment dam deformations. In terms of pseudo-spectral acceleration (PSA)-based IMs, the PSA at short periods and then in the general range of the natural period of the dams was seen to be the most efficient IM, but was in almost all cases not as efficient as AI. [ABSTRACT FROM AUTHOR]