40g-t水平单向离心振动台总体设计方法研究

Method study on overall design of a 40 g-t horizontal uniaxial centrifugal shaker

离心机上水平单向振动台振动容量大于30 g-t为大型离心振动台,振动容量40 g-t则代表国际当前大型离心振动台最高水平,目前仅美国和日本各有一台,经验少且自装备后一直不断改进。为满足我国岩土地震工程和土动力学对大型离心振动台装备的迫切需求,本文剖析了40 g-t水平单向离心振动台的功能要求与研制难点,论述了其总体设计思想,就动力源与作动器、导轨系统和与离心机接口等几个关键问题进行了讨论,给出了设计方法。研究表明,40 g-t离心振动台因振动容量和振动负载显著提高,与以往中小型离心振动台相比存在很多设计难点。本文提出的总体设计思想:使作动器轴线略高于模型台面以避免较大倾覆力矩;作动器与平台为滑动平面无间隙连接以提高系统固有频率;弹性剪切支座作导向支撑装置以提高运动稳定性;凹形平台以达到整体紧凑性;吊篮与运动平台及负载之间质量比可设计为3。

A horizontal uniaxial shaker with capacity above 30 g-t on a centrifuge is named a large centrifugal shaker.A centrifugal shaker with capacity of 40 g-t reaches the highest level in the present world.Only two such shakers exist in US and Japan respectively,but still are under continuous improvement,so there is exceedingly rare experience.In terms of urgent demand for a large centrifugal shaker in geotechnical earthquake engineering and soil dynamics in China currently,this paper analyzes the functional requirements and design difficulties of a 40 g-t centrifugal shaker,and presents its overall design ideas.Simultaneously the key technologies such as power sources and actuators,rail systems and interfaces to centrifuges are discussed,and the corresponding methods are also proposed.Compared with previous medium and small centrifugal shakers,analysis shows the design of 40 g-t centrifugal shakers under many significant difficulties due to marked increases in shaking capacity and shaking load.The overall design ideas include：the axes of actuators slightly above the shaker surface about models for avoiding large overturning moment;plane sliding interfaces between actuators and platforms without gaps for raising natural frequency;elastic shear bearings as guiding and supporting devices for improving motion stability;recessed shaker surfaces for achieving structure compactness;the mass ratio of buckets to moving platforms with payload is available by 3.