块状基础动态参数分析

摘要

机械工厂中有许多振动设备.结构设计时,对于这些动力机器基础和地基土体系可以按集总质量的方法来简化,即可以视其为质弹阻体系的力学模型.再由振动理论就可以得到该体系的频响函数.结合现场实体基础振动试验测试的结果,把幅频响应函数中的质量、刚度、阻尼比和固有频率等作为未知量,根据最小二乘加权逼近原理来识别系统中的动态参数.这种幅频响应加权最优参数识别技术与双峰法和多项式拟合法相比较,振动响应分析结果更为准确,用幅频响应参数识别法计算出来的残余误差最小,是计算分析的最佳参数.其中获取的动态参数与实际结构有明确的对应关系,这项技术已经在许多实际工程中应用.%There are many vibration machines in manufacturing industry. Their foundation on the ground can be regard as mass-springs-damp system. According to vibration theory, the function of its dynamic response can be sot up. To consider natural frequency, damp ratio and mass as unknown parameter, they are identified by weighting parameter optimization. It is a practical method, and has higher degreed of accuracy. The results of comparison of three methods calculation show weight optimization is hotter than double peaks method and Basavanna's.