| 0-3 cement-based piezoelectric composites exhibit reasonable piezoelectric activities as well as similar acoustic impedance to concrete stucture. Besides, the cement-based composites have the advantage of outstanding interfacial combination and excellent interface compatibility with civil engineering structures because of the utilization of cement as matrix. These are easily prepared with low cost, along with stable properties. Especially their piezoelectric property is pretty satisfying for the application, in order to be made into cement-based transducer in the concrete structure.In this paper, PZT piezoelectric ceramics were mixed with cement to fabricate cement-based composites with excellent piezoelectric properties.0-3 cement-based piezoelectric composites were prepared by compressing process, which adopted different kinds of PZT piezoelectric ceramics as a functional phase, Portland cement and white cement as matrix, and were reinforced and modified by a small quantity of carbon black and CNTs. The main content and results are as follows.0-3 cement-based piezoelectric composites were prepared in this research, employing P41, P43, P51 and P52, four types of piezoelectric ceramic composite materials as functional phases and Portland cement as matrix, and the piezoelectric and dielectric properties of piezoelectric composites were also studied. The results showed that the composites adding P51 and P52 held better piezoelectric properties and higher dielectric constant but more dielectric loss and impedance accordingly. Piezoelectric properties of piezoelectric composites increased with the growth of the content of piezoelectric ceramic. Furthermore this paper analyzed different kinds of cement influencing the properties of the composites, which showed that Portland cement made slightly huge contribution, and the composites possessed almost the same dielectric properties among the three cement matrix.In this study, the effect of particle size on the piezoelectric and dielectric properties of 0-3cement-based piezoelectric composites was investigated. The piezoelectric composites were prepared by mixing and pressing the white cement and PZT powder with different average particle size ranged from 3μm to 482μm. It was found that the piezoelectric strain factor(d33), dielectric constant(εr), and electromechanical coupling coefficient(Kt) increased with the growth of the PZT particle size. However, the composites with larger PZT particles had higher dielectric loss(tanδ) than those with smaller particles. According to the results of XRD, SEM and MIP, the inferior d33,εr and Kt values of the composites with small PZT particle size were believed to due to the increase of porous interface between PZT particles and cement matrix. Whereas, the low value of the composites with small PZT particle size was attributed to its compacted microstructure.Lead zirconate titanate (Pb(Zro.52Ti0.4s)O3) nanopowder was prepared using a sol-gel process. The results of the DTA/TGA, XRD, laser particle size analysis and SEM studies indicated that the PZT powder calcined at 700℃had perovskite structure with an average crystallite diameter of 26.4 nm and an average agglomerate diameter of about 200 nm. The 0-3 cement/nano PZT composite were fabricated by pressing the mixture of white cement and nano PZT powders. The piezoelectric properties of the cement/nano PZT piezoelectric composites have been measured. Comparing to the cement/PZT composite made by incorporating the ground PZT particles, the cement/nano PZT composite showed a better piezoelectric activities.0-3 cement-based piezoelectric composites, fabricated from white cement, PZT powder and small amounts of carbon black, were exploited for potential applications in civil engineering. The nature of the aging and poling behavior of the carbon black/PZT/cement composites was investigated. It was shown that the use of a conductive carbon black phase can facilitate the poling process at room temperature. The influences of the carbon black on the piezoelectric and dielectric properties were studied as well. It was demonstrated that the piezoelectric sensitivities of the composites can be dramatically enhanced by incorporation of small amounts of carbon black, due to its conductivity. With a poling field of 4kV/mm and poling time of 20min, the d33,εr, tanδand Kt values of the composites containing 70vol.% PZT and 1.0vol.% carbon black were 28.5 pC/N,202.6,0.19 and 12.2%, respectively. In this research, the influence of the dispersion of carbon nanotubes to PZT/cement piezoelectric composites had been investigated.0-3 CNTs/PZT/cement piezoelectric composites were fabricated with the PZT powders, cement and a spot of CNTs utilizing the compacting method. The behaviors of cement-based piezoelectric composites embracing different contents of MWCNTs, and several methods of dispersion and purification of them were investigated on the piezoelectric and dielectric properties. The results showed that the CNTs influenced the piezoelectric properties of cement-based piezoelectric composites to certain extent. The Fenton/UV method was a better method to disperse the CNTs. Fenton/UV method could remove the amorphous impurities inside the CNTs thoroughly. And HNO3 oxidation and Fenton method both enable the introduction on CNTs surface of functional groups such as-C=O,-COOH,-OH and so on. There was a conductive network in PZT/cement piezoelectric composites with CNTs dispersed to improve the conductivity among them. It could improve the polarization efficiency of PZT particles and strengthen the piezoelectric and dielectric properties of PZT/cement piezoelectric composites. When CNTs content reached 0.10 wt.%, d33 of the composites could become 46 pC/N for the HNO3 oxidation method, but d33 of the composites could come to 54 pC/N for the Fenton/UV method at 0.15 wt.% CNTs.
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