An intelligent and multifunctional composite for drainage pipeline monitoring based on deformation and temperature sensitivity

Digital twins are widely used in structural health monitoring, but their application in underground drainage pipelines is limited due to the harsh environment. This study presents a smart pipeline composite based on ultraviolet cured-in-place pipe (UV-CIPP) technology, integrating multi-walled carbon nanotubes (MWCNTs) with glass fibers to enhance both mechanical strength and sensing capabilities. Mechanical and electrical tests examined the effects of MWCNTs concentration, sensor layer configuration, and resin content on the material’s properties. The composite achieved a bending strength of 574.14 ± 23.84 MPa and demonstrated high sensitivity to real-time damage monitoring, with pre- and post-damage sensitivity reaching 14.76 and 46.40, respectively, at 0.2 wt% MWCNTs. In addition, the material exhibited a water temperature sensitivity of −10.67 % °C⁻¹, with good stability. It also demonstrated the ability to monitor water levels and provide heating for pipe de-icing. In summary, this composite material holds great potential for applications in pipeline structural health monitoring and multifunctional systems.