The Method Of Active Damage Monitoring For Concrete Structures Based On Piezoelectric Smart Aggregate

Construction structure damaged in earthquake will cause significant casualties and property losses, however the health monitor system is expensive and low survival rate in earthquake.So it’s difficulty to knew the procedure of damage in construction.In this paper,I article,I take a way to monitor the damage in earthquake,using Smart Aggregate sensor.In the article,I mainly have the following aspects:(1)The firstl, study the sensor whice send and receive message is always the samliar,with grinate to protect the PZT.Two sensors are sending and receiving message to each other to make sure the sensor’s property,in the same circumstance studies show that the sensor is used in this paper has a good repeatability.(2)The second, this paper compared the performance characteristics of the two kinds of sensors,one is protecetde in granite.the other is protected in cement. Through put the different sonsors at the same circumastance to find the better is SA protected by grintie,whice is better repeatability, higher signal-to-noise ratio and more suitable to monitor structure damage.(3)The third, put forward the concrete structure of small data active damage monitoring method. Using labview program to built concrete structure of small data active damage monitoring system. The system mainly consists of four major parts of NI high frequency signal acquisition instrument, NI signal generator, power amplifier and the SA sensor. The system is based on the analysis of wave sweep frequency of concrete beams, to find out the sensitive to structural damage and the frequency of received signal is larger, and takes the frequency as the active emitting frequency, in fixed time interval, automatically sending and collecting the millisecond frequency of sound waves. Through monitoring amplitude changes of the wave signal in different time, to achieve monitoring of internal damage of concrete structure. Use this method can greatly reduce the receiving the amount of data of SA, and can realize active monitoring of.continuous damage process.(4)The forth,through component damage test verify the effectiveness of the structural damage monitoring method of small amount of data. Damage of concrete beam component and cracking of bent column is researched, established the relationship the received signal amplitude changes with damage degree, study the feasibility and effectiveness of the small amount of data monitoring.