LAUSR

Cementitious composites reinforced with conductive nanoparticles, also known as smart composite-based sensors, are emerging as novel sensors for real-time monitoring of structures. The present study deals with the development of embeddable smart composite-based sensor (called as eSCS), for monitoring the damage evolution in large-scale beam-column (B-C) sub-assemblages. Firstly, a systematic approach has been developed to fabricate the sensors through incorporation of functionalized (-COOH) multi-walled carbon nanotubes (MWCNTs). The optimum dosage of CNTs required for developing sensors with maximum conductivity and piezo-resistivity was ascertained by determining the percolation threshold limit. The best performing eSCS was then successfully embedded at the critical locations of full-scale B-C joint specimens. The embedded sensors are used, for the first time, for damage monitoring of the B-C sub-assemblages subjected to reverse cyclic loadings. From the study, it is found that eSCS with 0.50 wt.% COOH-MWCNT shows excellent piezoresistive behaviour and gauge factors are found to be approximately 730, 457 and 396 for the applied compressive stress ranges of 2–4, 2–6 and 2–8 MPa, respectively. The embedded sensors showed the excellent strain sensing capability under reverse cyclic loading. The present study demonstrates the suitability of embedded eSCS sensors for robust structural health monitoring applications.