Studies of An Innovative Nonlinear Actuator for the Semiactive Control of Dispersed Civil Structures

用于分散土木结构半主动控制的创新非线性执行器的研究

• 批准号: 9703805
• 负责人: Sami Masri
• 金额: $ 23.78万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-10-01 至 2001-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9703805&HistoricalAwards=false
• 关键词: Studies; Innovative; Nonlinear; Actuator; Semiactive

9703805 Masri Presently used actuators to generate control forces are generally inadequate for limiting the response of civil structures under strong earthquake shaking. There is a critical need for a new generation of actuators that have the capability of adequately performing under strong ground motion which may induce significant nonlinear deformations in structures. The objective of this research is to develop an innovative semi- active damping augmentation device for controlling the seismic response of dispersed civil structures. The control procedure uses nonlinear auxiliary mass dampers with adjustable (adaptive) motion-limiting stops, located at selected positions throughout the structure, to inject an optimum amount of "chaos" in the structures dynamic response by disorganizing the orderly process of amplitude buildup. The degree of the structure's oscillation in the vicinity of each semiactive nonlinear actuator determines the actuator's actively-controlled gap size and activation time. By using control energy to adjust the actuator's critical parameters instead of directly attenuating the motion of the structure (which conventional active control methods do), a significant improvement is achieved in the total amount of energy expended to accomplish a given level of vibration control. A sequence of analytical and experimental studies by means of a bridge model to be provided with several innovative nonlinear actuators and subjected to multiple-support earthquake excitation by seismic shakers will also be conducted. ***

9703805 Masri 目前使用的致动器来产生控制力通常不足以限制土木结构在强烈地震摇动下的响应。 迫切需要新一代执行器能够在强烈的地面运动下充分执行，这可能会引起结构的显着非线性变形。 本研究的目的是开发一种创新的半主动阻尼增强装置，用于控制分散土木结构的地震响应。 控制程序使用非线性辅助质量阻尼器，其具有可调节（自适应）运动限制挡块，位于整个结构的选定位置，通过扰乱振幅积累的有序过程，在结构动态响应中注入最佳量的“混沌”。 每个半主动非线性致动器附近结构的振荡程度决定了致动器的主动控制间隙大小和激活时间。 通过使用控制能量来调整执行器的关键参数，而不是直接衰减结构的运动（传统主动控制方法所做的），可以显着改善完成给定水平的振动控制所消耗的总能量。 还将通过配备多个创新非线性致动器并通过地震振动台承受多支撑地震激励的桥梁模型进行一系列分析和实验研究。 ***