LEAP 2017


Twenty-four centrifuge model tests of liquefaction and lateral spreading, performed as part of a round robin test program, are shared and compared in the DesignSafe archive. Please see the general report section of the published project for an overview comparison and background of all of the experiments.


One document in the report (with “ReadMe” in the file name) describes the organization of the data archive. The comparisons presented in the general report section will serve as an index to help the users find individual experiments of interest. This data from 24 model tests is published as nine separate experiments in this archive (one experiment per centrifuge facility). Each “experiment” includes two or three model tests and each model test includes between one and three destructive shaking events. All of the tests modeled a 4 m thick deposit of Ottawa F-65 sand with a 5-degree surface slope in a rigid box. The tests covered a range of ground motion intensities and a range of relative densities to define the median response and the sensitivity of the response to relative density and shaking intensity. The nine centrifuge facilities involved in this test program included Cambridge University (UK), Ehime University (Japan), IFSTTAR (France), NCU (Taiwan), KAIST (Korea), Kyoto University (Japan), RPI (USA), UC Davis (USA), and Zhejiang University (China).

LEAP-UCD-2017 Workshop

Resource: M. Manzari, B. Kutter and M. Zeghal (2017), “LEAP-UCD-2017 Workshop” Walter Buehler Alumni Center, UC Davis, CA, December 14-15, 2017.

This workshop is a culmination of LEAP-UCD-2017, the first phase of an international phased validation effort involving centrifuge model testing, laboratory testing and numerical simulations. The work by the US PI’s (Manzari, Zeghal, and Kutter) is funded by NSF grants: CMMI 1635307, CMMI 1635524 and CMMI 1635040.

With inspiration drawn from VELACS project (1989-1993 K. Arulanandan and R. Scott), the US LEAP project concept began in 2011 when the PI’s (led by Manzari) submitted their first proposal to NSF to develop a process for benchmark centrifuge testing for validation of numerical simulations. In 2011, the PIs invited collaboration of Professors Susumu Iai and Gopal Madabhushi to join the project. Professor Iai was the first to be funded; hosting workshops in Kyoto in 2013 and 2014. At the 2013 meeting in Kyoto, the acronym LEAP (Liquefaction Experiments and Analysis Projects) was adopted, and other international collaborators from Japan (Ehime U. and Tokyo Tech), China (Zhejiang) and Taiwan (NCU) joined the effort.

A goal of this workshop was to assess the ability of numerical models to predict the lateral spreading of a 4 m deep deposit of uniform sand and also to evaluate the sensitivity of predictions and experiments to selected input parameters (ground motion intensity, frequency content, and soil relative density). Understanding the sensitivity of predictions and experiments to input parameters was a prerequisite to appreciating the significance of discrepancies between experiments and between experiments and simulations, especially in the presence of uncertainties and variability.

This phase of LEAP involved coordinated experiments at nine different centrifuge facilities and numerical simulations from eleven different numerical simulation teams. Each and every team member had made extensive effort and extensive contributions to this LEAP.