FEM Analysis And Optimization Design Of0-3Cement-based Piezoelectric Composite Materials

Cement-based piezoelectric composite materials,not only having goodcompatibility with concrete material, high interface bonding strength, but alsomaintaining higher piezoelectric properties and sensory sensitivity, are widely applied incivil engineering structures.The large-scale finite element software ANSYS10.0will bewell on piezoelectric coupling field simulation, and then comprehensively explore thedrive and sensing properties of piezoelectric ceramics and of cement-based piezoelectriccomposites.In terms of driving performance of piezoelectric ceramics, ordinary cement-basedpiezoelectric composite materials and interdigitated cement-based piezoelectriccomposite materials (ICPCM),systematic ANSYS simulation was carried on with staticanalysis,modal analysis, harmonic analysis, transient dynamic analysis and designoptimization in turn.The main conclusions are as follows,1.For piezoelectric ceramics and ordinary cement-based piezoelectric composites,maximum displacement and stress of z direction are present in the surface of the edgeposition, compared to piezoelectric ceramics, maximum displacement of z direction ofordinary cement-based piezoelectric composite materials increases up to10.9%,indicating that the piezoelectric strain constant d33of cement-based piezoelectriccomposite materials is increased.And using a series arrangement of a stacked structuremade of piezoelectric element that can increase its maximum displacement.For ICPCM,its x maximum displacement and stress and strain are two times larger than maximumdisplacement and stress and strain of y direction, showing a significant orthotropicproperties.2.Piezoelectric ceramics and ordinary cement-based piezoelectric compositematerials both have frequency phenomenon, showing no orthogonality.The ICPCMshow no repetition frequency phenomenon, further illustrating its unique characteristicof orthogonality.3.Piezoelectric ceramics and cement-based piezoelectric composite materials havea larger response frequency,the displacement and stress results of y and z direction getto response extreme in about400kHz, but still show the characteristics of steadyresponse.For the ICPCM, the strain of x and y direction are the same responsefrequency, and the response frequency range is smaller. 4.Piezoelectric ceramics and ordinary cement-based piezoelectriccomposite materials exist hysteresis effect, but the waveform has no effect,so thehysteresis effect is acceptable.while the hysteresis effect of ICPCM is moreapparent,and the waveform is tactless, showing that loading area of driving voltage hasgreat impact on the hysteresis effect, when making the ICPCM,we should ensurethat the positive and negative electrodes are symmetrical on the upper and lowersurfaces.5.For piezoelectric ceramics and ordinary cement-based piezoelectric compositematerials,the optimization design was carried on about the radius R and thickness H,the optimization scheme is similar, the optimization design is best when the radius Ris0.005m and the thickness H is0.0008m.For the ICPCM,the optimization design wascarried on about the thickness H and electrode center distance P and electrode width W,the optimization design is best when the thickness H is0.006m, the electrode centerdistance P is0.001m, the electrode width W is0.0007m.Finally, in terms of sensor performance, the static analysis and modal analysis ofpiezoelectric ceramics and ordinary cement-based piezoelectric composite materialswere carried on initially using ANSYS, obtaining the size and distribution of electricpotential and making the comparative analysis.For a particular piezoelectric element,when the amount of displacement (pressure) is constant, the voltage value increaseswith the increasing thickness of the piezoelectric element,for piezoelectric ceramics andcement-based piezoelectric composite materials,the repetition frequencyphenomenon still exists, although the first few frequencies are small, they are still notwithin the common engineering vibration frequency range,some measures are needed tomeet the requirement of vibration frequency.