A Feasibility Study on EMI Techniques and Disk-Shaped PZT Sensors for Strength Monitoring of Cement-Stabilized Loess

This article investigated the feasibility of electromechanical impedance (EMI) techniques, employing a developed disk-shaped (DS) piezoelectric sensor, for strength monitoring of cement-stabilized loess (CSL), a base material for pavement foundations. Through a series of experiments, the DS sensor was tested on CSL specimens under varying moisture conditions and applied loads. The results demonstrated that the DS sensor could precisely identify the optimal initial moisture content for achieving the maximum dry density in CSL, closely aligning with the conventional Proctor tests. Moreover, the EMI techniques were proven capable of monitoring the strength development of CSL during hydration. They also showed high sensitivity to changes in post-hydration moisture content, thus validating their feasibility for strength monitoring of CSL. However, the sensors exhibited limited sensitivity to applied loads on hardened CSL specimens. The findings demonstrated the potential of EMI techniques, facilitated by DS sensors, as a promising approach for the strength monitoring of CSL in fields.