Zhejiang University benchmark centrifuge test for LEAP-GWU-2015 and liquefaction responses of a sloping ground

摘要

A dynamic centrifuge model test of mildly sloping ground was conducted at Zhejiang University according to the LEAP-GWU-2015 experiment specifications. A 5-degree slope consisting of a saturated medium dense Ottawa F-65 sand was prepared by air pluviation method in rigid container, which simulated a prototype with a 20m length and 4m depth under 26g centrifugal acceleration. The model was subjected to three smaller and two destructive motions. Test data and preliminary analyses of model responses during multiple shakings are presented. In-flight measurement of shear wave velocity by bender elements was used to characterize the evolution of soil state. Acceleration response spectra were presented and site amplification effects were observed. Shear stress-strain loops were calculated from acceleration records, and asymmetric dilatancy in the sloping ground was observed during liquefaction. Generation and dissipation of excess pore pressure were depicted. Large liquefaction-induced ground displacements were measured and analyzed. This study provides valuable data and delivers some important observations of liquefaction responses of a sloping ground.