Kyoto University LEAP-GWU-2015 tests and the importance of curving the ground surface in centrifuge modelling. Issue 124 (September 2019)

• Record Type: Journal Article
• Authors: Tobita, Tetsuo; Ashino, Takayuki; Ren, Jianfei; Iai, Susumu
• Is Part Of: Soil dynamics and earthquake engineering. Issue 124(2019)
• Page Start: 259
• Page End: 267
• Publication Date: 2019-09
• Subjects: Centrifuge modelling -- LEAP-GWU-2015 -- Liquefaction -- Radial gravity; Soil dynamics -- Periodicals; Earthquake engineering -- Periodicals; Sols -- Dynamique -- Périodiques; Génie parasismique -- Périodiques; 624.176205
• DOI: 10.1016/j.soildyn.2018.05.005
• Languages: English
• ISSNs: 0267-7261

Abstract

Abstract: This paper presents a description of testing procedure and results of the LEAP-GWU-2015, and an investigation of the effect of the radial gravity field in centrifuge modelling. Dynamic responses of two models are compared. One had a planar surface with a 5° slope relative to the base of the container; the other had a curved surface to maintain a constant slope angle with respect to the radial g-field. For the centrifuge tests employed in this study, the slope and base excitation are in the tangential direction to spinning centrifuge. Results show that spikes in acceleration records due to cyclic mobility associated with lateral displacements appeared on both models. However, for the plane surface model, acceleration spikes in the negative (upslope) direction are more prominent and the residual downslope ground deformation was larger. Larger lateral displacement was observed in the plane model, while surface displacements in the curved model are smaller and uniform along the length of the model. For the plane model, the radial gravity acting near the slope top is almost constant and gradually increases towards the slope toe which causes a net increase in effective slope angle. Curving the model ground surface is recognized as leading to uniform lateral displacements along the length of the model surface. Highlights: Under the LEAP-GWU-2015, a physical model test under specified conditions is conducted. Dynamic responses of a saturated sloping ground forming either curved or plane surface are compared. Larger upslope acceleration and residual deformation was observed in the plane surface model. In the curved model, displacements were smaller and uniform along the length of the model. For centrifuge modelling, importance of curving the model ground surface was by the comparison.