A Feasibility Study on GFRP Tubular Concrete Column Damage Detection Using Piezoceramic-transducer-enabled Active Sensing

Cai Gaojie,She Yanhua

doi:10.11648/j.ajma.20190703.15

Abstract

Aiming at the crack damage of concrete in GFRP tubular concrete column, a method based on piezoelectric wave method was developed to monitor the crack damage. By transmitting and receiving stress waves from a pair of piezoelectric ceramic sensors embedded in GFRP tubular concrete, the damage degree of GFRP tubular concrete columns was evaluated by using wavelet packets to obtain the stress wave energy and damage index under different load levels. By analyzing the change of stress wave energy and damage index of concrete with different strength under different loads, the time-domain signal response, load-energy curve and load-damage index curve were obtained. In this test, four test pieces were designed according to different concrete strength grades. Two piezoelectric ceramic sensors were placed in the test piece and used to monitor the test piece under static loading. After the static loading was completed, the GFRP tube was severely broken and peeled off from the concrete. A large number of cracks appeared on the concrete surface. The results show that: The test results were consistent with the actual damage of the specimen. The development trend of concrete damage in GFRP tubular concrete columns was well revealed by the wave method.

Highlights

GFRP tubular concrete column was a combined structure formed by pouring concrete into the GFRP tube
The wall thickness (T) was 6 mm, the column height (H) was 250 mm, the cross section was a square with side length (L) of 100 mm, and the two sensors are 150mm apart, as shown in figure 2.A pair of piezoelectric ceramic sensors were embedded in the concrete of the GFRP tube
The results showed that the damage degree of the test piece was different, and the signal received by the sensor would be different

Summary

Introduction

GFRP tubular concrete column was a combined structure formed by pouring concrete into the GFRP tube. Compared with other confined concrete members, it had the advantages of strong bearing capacity, good integrity, high ductility, excellent corrosion resistance and easy construction. Due to factors such as the environment and age, cracks in concrete could seriously affect the safety of the structure. Health monitoring of concrete columns was crucial. Xiao et al [15] considered the influence of temperature on piezoelectric ceramic sensors. Huang et al [16] mentioned how piezoelectric ceramic sensors were placed in concrete so that energy could be better accepted. Yan [17] buried piezoelectric ceramic sensor in concrete structure for damage monitoring

Methods

Results

Conclusion