Damage evolution of steel-UHPC composite beams using AE and DIC techniques

The incorporation of Ultra-High-Performance Concrete (UHPC) in steel-concrete composite beams presents an outstanding solution for reducing crack propagation and enhancing ductility. In this study, three-point bending tests were combined with acoustic emission (AE) and digital image correlation (DIC) diagnostics to study the damage evolution in corrugated steel web I-beam UHPC composite beams. A clustering analysis method based on RA-AF-RC parameters was developed, and b-values and Kolmogorov-Sinai entropy were used for early warning analyses. The findings indicated that UHPC significantly enhanced the crack control capability of corrugated steel web I-beam UHPC composite beams. AE ringing counts and energy clearly indicated distinct, identifiable changes at various damage stages, serving as optimal AE monitoring parameters. AE clustering parameters were determined through principal component analysis and Laplacian scores, with K-means algorithm analysis confirming the alignment with actual crack patterns. K-entropy analyses provided early warnings for cracks, yielding, and failures, showing that b-values can effectively predict structural failures and that K-entropy is also effective in early warnings for structural cracks, yielding, and failures. This AE monitoring method offers a superior alternative to traditional monitoring methods, enabling real-time monitoring and early warning for damage evolution in composite beams.