Experimental Study On Damage Of Beam And Slab Members Based On EMI Technology

With the continuous development of national economy,the field of civil engineering in our country has made great progress.Large and complex structures are everywhere,and their design life is usually about 100 years.In order to ensure that the structure can meet its predetermined function within the design service life,it is necessary to carry out health monitoring on the structure.The traditional monitoring method has many disadvantages:it can not monitor the early damage of the structure;the sensing system and the excitation system are usually separated.Piezoresistance method is a kind of structural health monitoring method which combines sensing and excitation.It can detect the early damage of the structure under high frequency excitation.In this paper,one-dimensional steel beam structure and two-dimensional aluminum plate structure are tested and studied based on piezoresistance method and AD5933 data acquisition board.For the steel beam structure,the cutting machine is used to cut the damage of the same length,height and width on the steel beam at the same distance to simulate the impact of the damage distance on the conductance nano impedance spectrum,and the specific location of the damage is determined with the help of BP neural network;similarly,the cutting machine is used to cut the damage of the same height,width and length on the steel beam at the same distance to simulate the impact of the damage degree on the impedance spectrum.For the aluminum plate structure,the weight of the same mass is pasted in different positions and different mass is pasted in the same position to make the structure damage,and the quantitative analysis of the structure damage is realized by the arc positioning method.At the same time,the concept of data credibility is put forward,and the obtained data is optimized.Finally,a new method of PZT layout of the plate structure is put forwardIn this paper,particle swarm optimization(PSO)is introduced,the basic principle of PSO is introduced in detail,and it is applied to the damage location of two-dimensional plate structure.The influence of learning factor,inertia weight coefficient,particle number and other parameters on the accuracy of damage locationPiezoelectric ceramic chips used for health monitoring of practical engineering are in a complex natural environment,which are easily affected by various "variable forces".Therefore,this paper studies the influence of temperature,output voltage and conductor length on the impedance spectrum,and corrects the influence of temperature by means of translation compensation method and root mean square difference method.Finally,the conclusion and innovation of this paper are summarized,and the problems to be studied in this field are prospected.