LAUSR

In centrifuge modelling, in-flight soil conditions can vary horizontally depending on the location, i.e., from the center of model to a point close to the rigid wall. Moreover, loading history and earthquake shaking events affecting the particle contact force can influence the in-flight soil conditions. For reliable centrifuge modelling, therefore, it is important to evaluate the in-flight soil properties in a soil model at specific locations before target experiments are performed. A series of centrifuge model tests were undertaken on a uniform dry sand to investigate the in-flight soil parameters by measuring shear wave velocity (Vs) via bender elements (BE), as the Vs of the soil is directly related with soil properties. Three plausible conditions likely to influence the soil parameters were discussed in this paper: (i) boundary condition (location from the container boundary), (ii) load history (sequence of spinning up and down in the centrifuge), and (iii) earthquake shaking events. The Vs measured in the centrifuge was verified through comparison with resonant column (RC) test results. The results showed that the Vs is different in horizontal plane with locations within the model as well as with different loading events. The results also confirmed that the evaluation of in-flight soil properties before performing the test is important for interpreting the soil behavior accurately.