Piezoelectric sensor for monitoring internal unidirectional stress of component and application thereof

Abstract

The invention relates to a piezoelectric sensor for monitoring internal unidirectional stress of a component and application thereof. The piezoelectric sensor comprises a die body, a piezoelectric ceramic piece and a shielding wire, wherein an inner core at the front end of the shielding wire is fixedly connected with the piezoelectric ceramic piece, the piezoelectric ceramic piece is buried in the die body, the die body is provided with an annular groove in the periphery of the piezoelectric ceramic piece, so that only the upper portion and the lower portion of the piezoelectric ceramic pieceare contacted with the die body, and the periphery of the piezoelectric ceramic piece is not contacted with the die body; and the front section of the shielding wire and the inner core connected withthe piezoelectric ceramic piece are buried in the die body along with the piezoelectric ceramic piece, and the rear section of the shielding wire extends out of the die body. The pressure sensor is beneficial to accurately measuring the unidirectional stress in the component.

Description

technical field [0001] The invention belongs to the technical field of stress sensors, in particular to a piezoelectric sensor for monitoring unidirectional stress inside a component and its application. Background technique [0002] The monitoring of internal stress of structures under external loads has always been one of the important issues in the field of civil engineering. Research and development of reliable stress monitoring methods are of great significance to failure mechanism research and structural performance evaluation. There are some stress sensors, such as piezoresistive sensors, strain gauges, fiber optic sensors, etc. However, these sensors have disadvantages such as high price and poor compatibility with concrete, which lead to high monitoring costs and inaccurate monitoring results. Piezoelectric ceramic materials (such as lead zirconate titanate, Lead Zirconate Titanate, PZT for short) have the advantages of low price, fast response speed, and stable pe...

AI Technical Summary

Problems solved by technology

[0003] The existing piezoelectric stress sensor is in a three-way stress state when it is embedded in the component, while the sensor is in a one-way stress state when it is externally calibrated. The states of the two are inconsistent, resulting in the inability to accurately measure the internal stress of the component.

At present, most of the piezoelectric stress sensors are only externally calibrated, and have not been embedded in the component for verification

Moreover, the existing method for verifying the reliability of the sensor is to equate the stress at a local point into the stress of a plane. This method is suitable for ideal homogeneous materials, but for heterogeneous materials such as concrete and mortar, the equivalent method, that is, there is a large error in representing the stress of a section by the stress of a single point

Images