Research On Floor Vibration Analysis And Vibration Reduction Reinforcement Scheme Caused By Ground Source Heat Pump

In recent years,with the development of science and technology,in order to improve production efficiency,the working environment of mechanical equipment is inevitably transferred from outdoor to indoor.The vibration of mechanical equipment will inevitably have a certain impact on the building,which will easily lead to poor vibration of the structure.It will affect the safety and stability of the equipment and structure and threaten the physical and mental health of the operator while affecting the normal production work.Although the vibration caused by mechanical vibration can not be eliminated,we can control the vibration within the allowable range through various vibration control measures to reduce the impact on the building.Therefore,how to suppress the vibration response and reduce the structural vibration is an important research direction related to building safety.When a ground source heat pump in a L'Oreal R&D center building is running,the staff in the second-floor production operation feels obvious shaking,and the vibration response of the second floor slab is too large.On the basis of completing the on-site vibration test of the structure,the finite element software is used to analyze the vibration characteristics of the floor,to find out the cause of the vibration of the floor,and several possible vibration reduction schemes are proposed.Considering the rationality and feasibility of these several schemes,find out the optimal vibration reduction and reinforcement scheme,and provide reference for the vibration reduction projects of similar projects in the future.The main achievements of this paper are as follows:(1)The principle and method of dynamic performance test are introduced.The dynamic performance test of the structure is carried out to obtain the acceleration response of different positions of the structure under the same working condition.As the vibration of the pump causes ground vibration and pipe vibration,the ground vibration is transmitted upward through the columns,walls and other components,and the pipe vibration is transmitted to the second floor and above along 27 rigid support points.At the same time,the actual frequency of the floor vibration is 50 Hz,which is consistent with the ground source heat pump disturbance frequency.It is presumed that the resonance caused the vibration of the two floors to be too large.The vibration test results show that the acceleration of each measuring point exceeds the specification limit,and does not meet the requirements of human comfort.The vibration control of the structure is required.(2)According to the existing project data,the ANSYS finite element model is e stablished by selecting the appropriate material parameters and unit types,and the mod al analysis is performed to obtain the mode vibration frequency of each structure.The simulation results are compared with the results of the dynamic measurement.The si mulation results are consistent with the dynamic measurement results.It is considered t hat the finite element model can accurately reflect the dynamic parameters of the struc ture and can be used for further vibration reduction analysis.Through the harmonic res ponse analysis,the displacement-frequency response curve of the maximum vibration of the vertical vibration of the floor is obtained,and the frequency segment where the maximum displacement of the structure occurs is found.The reason for the final deter mination of the excessive vibration of the second floor slab is that a resonance effect occurs.(3)Combined with the results of finite element analysis,in order to solve the vibration problem of structural slabs,three kinds of vibration reduction schemes are proposed to increase the reinforcement of secondary beam section,vibration isolation of vibration isolator and vibration control of MTMD system.The parameters are designed and optimized for different schemes,and the finite element model is established to calculate the dynamic performance parameters of each scheme for different schemes.The vibration damping efficiency of the three schemes is analyzed.It is found that all three schemes can weaken the vibration response to a certain extent.Under the condition of considering various factors,the vibration isolation scheme is determined as the optimal solution,and reasonable suggestions for vibration damping and reinforcement of such engineering are given.