Fabrication and verification of vertical graphene-based strain sensor

The purpose of structural health monitoring in civil and mechanical engineering infrastructure is to make a structure safer at a lower cost. Strain, one of the crucial monitoring variables, has an innate relationship with deformation and is sensitive to the degeneration of load-bearing structural elements. In this study, a set of wireless real-time data acquisition and strain monitoring systems based on vertical graphene (VG) were developed. Both the parametric study and the feasibility of the VG-based strain sensor in crack monitoring of concrete structures were investigated. The greatest resistance difference in the cyclic tensile test is 2.99%, and the linearity is 2.4%, proving the newly designed sensor has good repeatability and stability. According to the monotonic tensile test based on a micro-displacement control platform, the relative resistance to change & UDelta;R/R rises as applied strain rises and the repeatability error results in 0.576%. According to the notched concrete beam under the three-point bending test, the VG-based strain sensor's discrepancy from the extensometer's monitoring data is within 11.04%. The findings of this study suggest that the newly developed VG-based strain sensor has the potential for practical application in field strain monitoring, thus reaffirming the feasibility and effectiveness of this novel sensing technology.