LEAP-ASIA-2019 Centrifuge Tests at University Gustave Eiffel

Abstract

AbstractIn the framework of the LEAP-ASIA-2019 exercise, two dynamic centrifuge tests on a gentle slope of saturated Ottawa F-65 sand have been performed at the centrifuge of University Gustave Eiffel. These tests were conducted in parallel with other tests performed in nine other centrifuge centers. In addition to the objectives of the LEAP-UCD-2017 (comparison of the experimental results, e.g., effect of the experimental procedure or of test parameters on the results, and providing of a database for numerical modeling), the new objective was to evaluate, through the tested configuration, the generalized scaling approach described by Iai et al. (Géotechnique 55(5):355–362, 2005). In this framework, all the centrifuge teams have performed two types of tests. Considering the same prototype geometry, the first test was performed following the classical approach used in centrifuge modeling, and the second test was performed considering the generalized scaling law (GSL). Following the test matrix and test specifications of LEAP-ASIA-2019, University Gustave Eiffel has performed two model tests (test A2 renamed UGE-1/50-62 and test A3 renamed UGE-2/25-62). The two tests have been performed on a slope sand with the same relative density (62%) considering a target motion PGAeff = 0.3 g (1 Hz ramped sine at the prototype scale).In this paper, the test setup and the deviations from the specifications such as the experimental setup improvement that have followed the LEAP-UCD-2017 tests are presented in detail. The results obtained from the two tests are then provided at the prototype scale for comparison. The obtained input base motions are first presented followed by the characterization of the soil through CPT profiles. The responses of the saturated sand slopes for both tests are then detailed through the analysis of the pore pressure buildup, the accelerations in the soil, and the displacements measured through surface markers and embedded sensors. Some preliminary results of the global scaling approach are then discussed.