Plan for participatory research project on soil liquefaction under multiple earthquakes

Abstract

In recent large-scale earthquake events, such as the 2011 off the Pacific coast of East Japan Earthquake, large foreshocks and aftershocks as well as the main shock had been observed at short interval. For instance, the following key factors can be considered in the soil liquefaction under multiple earthquakes: 1) intensity and interval of earthquake ground motions, 2) drainage capacity of the ground, 3) residual pore water pressure, 4) soil properties during water pressure dissipation process and after liquefaction, 5) damage status of pile foundation and embedded pipeline due to previous large motion. Soil liquefaction and associated damage from a single earthquake can be assessed by using existing assessment approach and the initial conditions, such as investigation results. However, for liquefaction caused by multiple earthquakes, it is important to estimate the ground properties including recovering due to pore water dissipation and damage status of foundation at the time of the next large earthquake motion. Because soil conditions are considerably different at each site, it is significant to collect any kind of data including experiments, numerical analysis, soil investigation, reconnaissance results under various conditions to make comprehensive estimation. To develop their dataset available for various purposes, National Research Institute for Earth Science and Disaster Resilience are planning to perform participatory research project. In this project, one of the core works is E-Defense large-scale shaking table test and the test data will be available for any participant and for any kind of researches. In this paper, contents, schedule of this project are described.