Experimental Study On Electrial-mechanical Response And It's Damage Of 1-3 Cement Based Piezoelectric Composites Under Impact Loading

With the development of social economy,on-line health monitoring and forecasting by using the intelligent sensor monitoring system have been widely used in important concrete construction projects.Cement-based piezoelectric composite material have the advantages of low acoustic impedance,high electromechanical coupling coefficient and low mechanical quality factor.This new kind of functional material which can effectively solve the compatibility problem of general intelligent materials and concrete structural materials.Not sensitive to humidity,can be used in concrete environment for long time.The failure of an intelligent material means that it has lost its due functions.The intelligent sensors embedded in the concrete structure will be subjected to static or dynamic loads along with the structure.The sensor signal is abnormal and even fails.The research on the coupling performance of intelligent sensing materials has attracted widely attention.In this paper,specimens of 1-3 cement based piezoelectric composites were fabricated with the method of cutting-casting,in which PZT5 H is used as a function of body,Portland cement is used as matrix.The electro-mechanical responses and damage law of the PZT5 H and 1-3 cement based piezoelectric composites are researched under quasi static loading and dynamic loading respectively.The quasi-static compressive experiment and impact compressive experiment of PZT5 H and 1-3 cement-based piezoelectric composites were carried out by using MTS servo testing machine and Split Hopkinson Pressure Bar(SHPB)device.The experimental results have shown that the electric displacement and stress of the two kinds of materials have good electro-mechanical responses under impact loading.The stress or the electric displacement increased with the increase of strain rate at same strain or same stress respectively.At the same time,during a certain strain rate range,the failure electric displacement increased with the increase of strain rate under impact loading.Under the quasi-static loading,due to the phenomenon of domain reversal,the amplitude of the electric displacement of the materials decreased with the increase of the cycles of loading.With the increase of the number of loading cycles,the residual strain of the material increased,but contrary changed in electric displacement amplitude and the residual electric displacement.With the increased of the repeated cycles,the piezoelectric properties of the piezoelectric material became weaker and weaker until failed on the response of mechanical and electrical.