Abstract
Self-sensing concrete materials, also known as smart concretes, are emerging as a promising technological development for the construction industry, where novel materials with the capability of providing information about the structural integrity while operating as a structural material are required. Despite progress in the field, there are issues related to the integration of these composites in full-scale structural members that need to be addressed before broad practical implementations. This article reports the manufacturing and multipurpose experimental characterization of a cement-based matrix (CBM) composite with carbon nanotube (CNT) inclusions and its integration inside a representative structural member. Methodologies based on current–voltage (I–V) curves, direct current (DC), and biphasic direct current (BDC) were used to study and characterize the electric resistance of the CNT/CBM composite. Their self-sensing behavior was studied using a compression test, while electric resistance measures were taken. To evaluate the damage detection capability, a CNT/CBM parallelepiped was embedded into a reinforced-concrete beam (RC beam) and tested under three-point bending. Principal finding includes the validation of the material’s piezoresistivity behavior and its suitability to be used as strain sensor. Also, test results showed that manufactured composites exhibit an Ohmic response. The embedded CNT/CBM material exhibited a dominant linear proportionality between electrical resistance values, load magnitude, and strain changes into the RC beam. Finally, a change in the global stiffness (associated with a damage occurrence on the beam) was successfully self-sensed using the manufactured sensor by means of the variation in the electrical resistance. These results demonstrate the potential of CNT/CBM composites to be used in real-world structural health monitoring (SHM) applications for damage detection by identifying changes in stiffness of the monitored structural member.
Highlights
It is a fact that materials and structures degrade withCastañeda‐Saldarriaga et al Int J Concr Struct Mater (2021) 15:3 reliability of structures in their long lifetimes
The aim of this paper is to present a multipurpose study that includes the characterization of cementitious composites with inclusions of carbon nanotube (CNT), different test procedures, and a proof-of-concept demonstration in a supported beam made of reinforced concrete of the suitability of these types of sensors for strain-based structural health monitoring (SHM)
The novelty of this study focuses on the effective integration of the self-sensing concrete sensors in a structural member and in using information from them for damage detection based on strain, demonstrating their suitability for future practical SHM applications
Summary
It is a fact that materials and structures degrade withCastañeda‐Saldarriaga et al Int J Concr Struct Mater (2021) 15:3 reliability of structures in their long lifetimes. Some NDT methods include visual testing (both direct and remote) Agnisarman et al (2019), ultrasonics Zhao et al (2018), acoustic emissions Meo (2014), infrared thermography Yamazaki et al (2018), ground penetrating radar techniques, and electrical resistivity tomography Salin et al (2018). These methods commonly require human intervention that increases uncertainty and implies costly equipment and personnel. SHM can reduce costs by providing valuable information for maintenance management, improve reliability by the possibility of finding damages at incipient stages, and improve future designs by making available valuable information about the performance of the current ones Ogai and Bhattacharya (2018)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
