Detection of crack development in steel fibre engineered cementitious composite using electrical resistivity tomography

Engineered cementitious composite (ECC) is a cement-based material which is fabricated with different types of functional filler, such as polyvinyl alcohol (PVA), to improve its mechanical properties. ECCs made of conductive fillers such as steel fibre (SF) also have high potential for self-sensing. In this study, a new electrical resistivity tomography method was introduced for SF-PVA ECCs based on the self-sensing property for detecting crack development. To study the feasibility and accuracy of the proposed method, specimens were first prepared with different scenarios of artificially introduced cracks, designed based on the most commonly occurring crack patterns in practice. The resolution of the proposed method was also studied with various sizes of single-edge cracks. On the basis of successful identification of the development of artificially introduced cracks, uniaxial tensile tests were conducted on SF-ECC plates to identify actual crack propagation using the proposed method. The findings of this study provide a sound and convenient method for in situ damage detection and structural health monitoring of ECCs or other conductive cementitious materials. (paper)