Robust evaluation of self-healing efficiency in cementitious materials – A review

Measurement of fracture mechanics parameters of concrete containing fly ash thanks to use of Digital Image Correlation (DIC) method

Using digital image correlation to evaluate fatigue behavior of strengthened reinforced concrete beams

Concrete structures with various reinforcements, such as steel bars, composite material tendons, and recently steel plates, are commonly used in civil infrastructures. When an external force overcomes the strength of the bond between the reinforcement and the concrete, bond-slip will occur, resulting in a relative displacement between the reinforcing materials and the concrete. Monitoring bond health plays an important role in guaranteeing structural safety. Recently, researchers have recognized the importance of bond-slip monitoring and performed many related investigations. In this paper, a state-of-the-art review on various smart sensors based on piezoelectric effect and fiber optic technology, as well as corresponding techniques for bond-slip monitoring is presented. Since piezoelectric sensors and fiber-optic sensors are widely used in bond-slip monitoring, their principles and relevant monitoring methods are also introduced in this paper. Particularly, the piezoelectric-based bond-slip monitoring methods including the active sensing method, the electro-mechanical impedance (EMI) method and the passive sensing using acoustic emission (AE) method, and the fiber-optic-based bond-slip detecting approaches including the fiber Bragg grating (FBG) and the distributed fiber optic sensing are highlighted. This paper provides guidance for practical applications and future development of bond-slip monitoring.

https://www.mdpi.com/1424-8220/19/5/1231/pdf

Bond-Slip Monitoring of Concrete Structures Using Smart Sensors-A Review.

Crack monitoring is crucial for safety, cost-effective design and maintenance of concrete structures. Most stand-alone crack monitoring techniques have some limitations in characterizing concrete c...

Improved crack monitoring in structural concrete by combined acoustic emission and digital image correlation techniques

Use of digital image correlation technique in full-scale testing of prestressed concrete structures

Summary

Prestressed concrete (PC) bridge girders have extra flexural strength due to embedded prestressing tendons. The level of strength depends on the integrity of the concrete-tendon bond in pretensioned PC structures, and this bond can be degraded in the presence of an adequately large mechanical force or over time because of accumulated damage. Bond degradation is characterized by the bond slip of the tendon from the host concrete, and in regards to PC structures, bond slip has only been measured from a global perspective. In this paper, a novel method was developed to measure for the first time the local strain of a prestressing tendon during bond slip. Fiber Bragg grating-based strain sensors were installed directly onto prestressing tendons within a PC girder to provide a local perspective of bond slip as the girder was loaded to failure. Measurement of the local strains in selected tendons, from the beginning of bond slip to the complete loss of the concrete-tendon bond, and the failure of the girder was enabled by the method. Copyright © 2014 John Wiley & Sons, Ltd.

Aadit Kapadia

Papers

Use of digital image correlation technique in full-scale testing of prestressed concrete structures

Inference of bond slip in prestressed tendons in concrete bridge girders