Experimental Study And Numerical Analysis Of Vibration Isolation Barrier Under Impact Load

At present,China is gradually promoting the process of urbanization and industrialization,during which a series of engineering construction and environmental impact problems will inevitably be brought,such as the environmental vibration problem which attracts more and more attention.The most common vibration sources of environmental vibration in daily life are traffic,construction and power machines,and the vibration caused by the most is low frequency.Nowadays,people have studied more vibration problems in traffic lines,but the vibration of impact load is ignored relatively.The impact load produced in pile foundation sinking construction,forging hammer forging operation,dynamic compaction foundation treatment,earthwork or foundation pit blasting will often bring immeasurable harm to nearby sites,buildings or equipment.In this context,it is necessary to study the vibration isolation and vibration reduction measures under impact load.As a kind of vibration isolation measure for the transmission path,the vibration isolation barrier has the advantages of good vibration isolation effect and strong applicability.Therefore,this paper mainly conducts systematic experimental research and numerical simulation analysis on the vibration isolation effect of the barrier from three aspects,including theory,test and numerical simulation analysis.The main contents of this paper are as follows:1.According to the wave theory,the wave and wave equation in elastic medium are introduced briefly,and the vibration response under the vertical concentrated force in elastic half space is discussed;the propagation and attenuation law of vibration wave in the foundation soil are introduced,and the mechanism of vibration barrier is also described.2.Through the field test of the vibration barrier,the law of the propagation and attenuation of the vibration wave formed by the impact load in the foundation soil is studied.On this basis,the vibration isolation mechanism and vibration isolation effect of the air channel barrier are discussed.The different influence of the different geometric dimension factors on the vibration isolation effect of the barrier is studied.3.The Midas GTS,a large general geotechnical engineering finite element software,is discussed in detail The basic methods of NT in the analysis of dynamic action are also discussed,including eigenvalue analysis,dynamic time history analysis,time step control,soil constitutive model selection,material damping determination,mesh size division and model boundary determination methods.At the same time,the modeling process and parameter selection are introduced in detail,and the above methods are used to analyze and introduce the modeling process and parameters selection The three-dimensional finite element model is used to simulate the numerical simulation under different space dimensions.Finally,the field test results and numerical simulation results are compared and analyzed,which proves the feasibility,rationality and accuracy of the numerical simulation method.4.After the numerical simulation method is proved to be feasible and effective,the paper analyzes several important parameters of vibration barrier under impact load,including the four factors,such as vibration source location,filling material,soil properties and vibration source frequency,and summarizes the rules,which provides reference for the actual engineering construction and design.