Research On Dynamic Stiffness Of Power Machine

With the rapid development of industry, great quality, high-power, high-speed,high-precision power machine has been widely applied in many industry domains,and also, the requirement for controlling vibration of structure has become more andstricter. Dynamic load force (inertia disturbing force), which generated by runningmachine, can make structure-foundation-pile-soil system vibrate. However, theabnormal vibration occurs frequently in recent years. Therefore, how to control thedynamic machine foundation vibration problems is a very urgent task.The major factor of controlling structure-foundation-pile-soil system vibration istwo: excitation force and dynamic stiffness. For the operating requirement of amachine, it’s a bad choice to adjust the working speed. On the one hand, thefoundation spread upper load to the soil and provide reliable support for the wholestructure; On the other hand, the dynamic stiffness of foundation affect the dynamicresponse of the structure. So, in order to control the structure vibration, this articlemainly focuses on the factors that affect the dynamic stiffness of a foundation.This paper discusses two different dynamic stiffness theory of dynamic machinetheoretical model calculation (mass-spring-damper model and elastic half-spacemodel) and also introduces the theory of dynamic stiffness of pile foundation, whichprovides the theoretical calculations for the engineering design.The research object of this paper is the foundation of DZQ-1600-D18hydrauliclock pillar stone cutting machine in one factory in Hengyang Area, Hunan. Thedynamic characteristics of a stone cutting machine foundation are obtained by modaltest under different operating conditions, and test results reveal that the main cause ofabnormal vibration lies in lower dynamic stiffness of the whole structure and pointengineering reinforcement to the right direction.Using the ABAQUS finite element software to analyze the factors affecting thedynamic stiffness of the structure-foundation-pile-soil system, it can provide guidancefor engineering design and engineering reinforcement; at the same time, their resultsare also suitable to other structure-soil interaction problems.