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Name of experiment：application of high voltage amplifier based on piezoelectric ceramics to the interface damage identification of double block sleeper and ballast bed

Research direction：nondestructive testing

Content of experiment：according to the typical interface states of sleeper and ballast bed, such as health condition, local crack, partial debonding, complete debonding and no contact, five kinds of composite specimens corresponding to the working conditions were designed and made. A method was proposed to detect the interface damage of sleeper and track bed by placing piezoelectric ceramic pairs near the interface for stress wave measurement.

Test equipment：piezoelectric driver, data acquisition card, signal generator, high voltage amplifier ATA-2022H, specimen, etc.

Experimental process：

1.The layout of piezoelectric ceramic plate and the construction of platform

According to the position of the interface and the vibration mode of the transducer, the appropriate position of the specimen was selected to post the piezoelectric ceramic plate.

schematic diagram of piezoelectric ceramic division

 2.Test setup: the signal is amplified by the high voltage amplifier and excited to the driver. The data acquisition system is used to collect the stress wave response received by the sensor, and the monitoring terminal can store and analyze the data.

3.Test procedure

The input voltage amplitude and frequency of the excitation signal were selected to test the specimens under 5 working conditions. Based on the A-Al path, B-BI path and CCl path, five completely separate tests were carried out on five different bonding states of sleeper and ballast bed composite specimens.

test path

Result of experiment：

Both sinusoidal and sweep excitation tests can identify health conditions, local cracks, partial disbonding, complete disbonding and no contact, and the results are related to the symmetry of the arrangement of specimens and piezoelectric ceramic pieces.

time domain amplitude of response signal under sinusoidal excitation of different frequencies

total energy of response signal in 5 working conditions under sweep excitation on path