结构阻尼模型及系统时域动响应

Structural Damping Model and System Dynamic Response at Time Domain

振动界对经典的非频变结构阻尼模型一直有种种争议,本文检查了它的前提并指出将该模型推广到系统时域动响应分析时导致的悖论.为了提供结构阻尼系统的时域动响应实用分析方法,文中分别提出了基于响应优势谱成份的粘性阻尼近似模型和基于粘弹性理论的三参数频变结构阻尼模型;它们既可逼近结构阻尼缓频变的特性,又可保证系统的时域动响应具有因果性.

The classical frequency-invariable model of the structural damping has recieved great attention and arguments for several decades. The paper examines its presupposition and points out the paradox of the model extension to dynamic analysis at time domain. To simplify the dynamic analysis of the structural damped system at time domain, the paper presents two frequency-variable models, which are respectively based on the viscous damping equivalence to the structural damping for the dominant spectrum of dynamic response and the standard linear solid model in visco-elasticity theory. The two models not only approximate to the classical structural damping in frequency behavior, but also guarantte the response causality of the system at time domain.