Underground Space Form Design of Large Centrifugal Shaker System and Analysis of Machine Foundation Vibration

Abstract

Centrifugal shakers are accounted the most effective and the most advanced test method of geotechnical earthquake engineering and soil dynamics, for a unique ability of exerting dynamic loads of sine waves and seismic waves on models while the same gravity stress as prototype is produced. Large centrifugal shakers are necessary to countries of frequent earthquake occurrences, but no one has been built in China. As state-of-the-art test equipments, its construction absolutely has many challenges. In the machine foundation design, its underground space employed a narrow rectangle as usual can’t satisfy the required space of facilities, while the imbalance force of equipments against foundation stability is inherently high. For no relevant research findings can be available, the paper states the general layout of a large centrifugal shaker and the fiendish problems between two space forms. By theories of mass-spring-damper and elastic half-space, two foundation vibration mathematical models for large centrifugal shakers are proposed. The calculation results of both underground space forms show that a round space meeting the required space of facilities doesn’t significantly increase foundation vibration, and is more ideal. Moreover the view of a narrow rectangular underground space more stable to large centrifugal shakers by experience is not true.