Development of self-sensing engineered cementitious composite sensors for monitoring flexural performance of reinforced concrete beam

In this paper, self-sensing engineered cementitious composite (ECC) was prepared and post-processed to obtain self-sensing ECC sensors. The sensor piezoresistive effect was modified considering the constraint of concrete. Then the sensor was embedded in the reinforced concrete beam to analyze the sensing performances under different conditions. The results show that the modified piezoresistive effect formulas were obtained by introducing correction coefficients, the formulas can describe the relationship between strain and impedance well. Sensors embedded in concrete beams cannot affect the bending performance and the development of cracks. The sensor can be used to monitor the strain in the compression under loading and unloading process of the beam and its sensing performance has good linearity, repeatability and accuracy. In the tension, when cracking, the sensors maintain the monitoring ability, but the accuracy needs to be improved. The gauge factor of the sensor applied in the beam is above 130.