Signal-Level Fusion Approach for Embedded Ultrasonic Sensors in Damage Detection of Real RC Structures

Abstract

This paper presents a novel methodology to fuse signals from multiple ultrasonic sensors and detect cracks in the reinforced concrete reference structure using nondecimate discrete wavelet transform. The behaviour of a reinforced concrete structure subjected to operational changes is considered. The changes/damage detection procedure is based on a novel sensor fusion method. Several advantages of the proposed approach using the sensor fusion method with respect to features from single pair of sensors were shown and discussed based on the tested objects. A CWT feature-based approach is considered to extract damage-sensitive features. Experimental results using the proposed approach show a probability of detection greater than 94% when detecting cracks due to quasistatic load. Due to the comprehensive effectiveness and low computational complexity, the proposed approach could be performed in large real structural damage assessment problems as well.

Keywords

• ultrasonic NDT
• signal processing
• signal level fusion
• reference reinforced concrete structures
• damage detection
• wavelet transform