Experimental Study On Early Strength And Crack Repair Of Concrete Based On Piezoelectric Sensing Method

It has been more than 10 years since the application and research of smart aggregate in engineering structures.In addition to satisfactory results in structural damage detection,its monitoring of concrete curing and crack repair also has promising prospects.In this paper,the study on monitoring of the strength of concrete and the effect of crack repair based on smart aggregate is carried out,and the main content is as follows(1)This paper introduces the background and significance of this research,and then describes the study of the research on the smart aggregate in the concrete age strength and crack repair monitoring.(2)This paper introduces the characteristics of the smart aggregate used in the experiment,the advantages and disadvantages of wavelet packet energy analysis and power spectral density analysis.(3)In this paper,an experimental scheme for monitoring the change of concrete strength based on piezoelectric smart aggregate is proposed.A reinforced concrete specimen is designed and fabricated,and the smart aggregate is embedded in the specimen.In this paper,the signal of sensor reception in the target age of 0-28 d is analyzed by using wavelet packet energy analysis and power spectral density analysis.By comparing the two methods of analysis,the trend of the strength of concrete is reflected.The accuracy of wavelet packet energy analysis and power spectral density analysis in the analysis of concrete strength change signal is proved.At the same time,it also shows that it is feasible to monitor the development of concrete strength based on smart aggregate.(4)In this experiment,the analysis of the signals from sensors received by the sensor in three states with cracks,complete and crack repair were analyzed by the time domain analysis and the wavelet packet energy analysis.The results show that the time domain analysis can clearly show that the amplitude of the concrete in the complete state is larger than that of the concrete under the condition of cracks.Second,through the analysis of wavelet packet energy,it is found that the energy received by the sensor is better than that of concrete under the condition of crack.However,the energy values of both are far less than the value of the complete state of concrete.The results show that the monitoring of the concrete age strength and crack repair based on the smart aggregate is feasible.