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Investigations on the liquefaction resistance of an open-cast lignite mine soil under loading by earthquake-typical signals For the embankments of the planned opencast mining lakes in the Rhenish mining area, the proof of the stability under earthquake action must be provided. According to the guideline for the investigation of the stability of slopes in lignite opencast mines (RfS - Richtlinie f & uuml;r Standsicherheitsuntersuchungen [1]), the permanent slopes must be designed and constructed in such a way that a soil liquefaction is not to be expected. For the proof, in which actions and soil resistances are locally compared with each other, the irregular earthquake signal is converted into a regular signal with an equivalent number of cycles and constant amplitude. In this paper, this conversion is investigated for a typical earthquake signal of the Rhenish area, which was obtained from a dynamic finite element calculation. Triaxial tests with vertical cyclic loading and hollow cylinder triaxial tests with cyclic torsional loading are performed to investigate the liquefaction behaviour of an opencast mine soil under the influence of this earthquake signal. The results of these tests are compared with data from further tests with constant amplitude. It can be shown that the factor beta for converting irregular to regular signals depends on the type of loading and the magnitude of the static shear or deviatoric stress. On the basis of the experiments, recommendations for the choice of beta for the Rhenish mining area are given.

来源平台：GEOTECHNIK