An axial piezoelectric stress sensor that can isolate lateral restraints is researched and developed

to meet the needs of concrete defect damage detection and uniaxial stress monitoring.The sensing mechanism and working performance of the new type stress sensor under quasi-static loading conditions with a strain rate of 10

-5

～10

-1

/s are studied.The studies show that the PZT element in traditional piezoelectric stress sensor is affected by the lateral restraint

and the measured uniaxial compressive stress cannot correspond to the collected charge; the proposed sensor has good sensitivity and stable working performance under quasi-static loading

and is not affected by the loading rate and loading type; the new type sensor has wider

range than the traditional sensor.