Experimental study on acoustic emission and surface morphology characteristics of concrete under different fracture modes

•The high-performance concrete under two curing regimes (i.e., standard curing and steam curing) are investigated under four fracture modes.•AE b value can be considered as a precursor index of concrete structure instability.•The fracture surface has been reconstructed by the 3D scanning technique, and qualitative and quantitative analyses have been conducted.•A 2D micro-element model is proposed to assess the interaction mechanism of fracture behavior and the associated fracture morphology characteristics, and a larger tangential deformation resulting in a rougher fracture surface.