Fracture behaviour analysis of the full‐graded concrete based on digital image correlation and acoustic emission technique

Abstract

Three-point bending tests of the full-graded concrete under different loading rates were carried out. The cracks were quantitatively analyzed by digital image correlation (DIC). The toughening mechanism during the crack development process was observed, and there are obvious crack branching and aggregate interlocking during the crack propagation. At the same load level, the crack opening width increases with the increase of the loading rate. DIC detects a decrease in the tortuosity of the fracture morphology. And at the same time, the damage of the dam concrete was evaluated by the frequency analysis and the damage type analysis from acoustic emission (AE) signals.The signal strength increases at a higher loading rate as well as the tensile type cracks. The results show that the monitoring results of DIC and AE technique are in agreement with each other, which is very effective for determining the fracture behaviour of concrete materials. Highlights• The aggregate interlocking and crack branching form the toughening mechanism after peak • The interlocking and crack branching decrease with the increase of the loading rate. • Signals with different frequency content correspond to different fracture scale. • The development type of crack tends to direct tension with the increase of the rate. K E Y W O R D Sacoustic emission, dam concrete, digital image correlation, fracture behaviour

Deformation and fracture behavior of strong–weak coupling structure and its application in coal roadway instability prevention

“…It is stipulated that the X‐ and Y‐directions in the plane coordinate refer to the horizontal and vertical directions in the Vic‐3D strain measurement system 58 . Parameters characterizing the deformation properties of the specimens include coordinates X , Y , Z , horizontal strain Exx , vertical strain Eyy , horizontal displacement U , vertical displacement V , horizontal strain rate dExx / dt , vertical strain rate dEyy / dt , horizontal displacement rate dU / dt , and vertical displacement rate dV / dt .…”

Fracture Behaviour of Real Coarse Aggregate Distributed Concrete under Uniaxial Compressive Load Based on Cohesive Zone Model

“…Then the fracture behaviour of crack a is analyzed through displacement contours. The colour of the x-direction displacement contour changes abruptly on both sides of the arrow, which means the crack exists at this place [ 45 , 46 ]. The shape and position of this crack are consistent with crack a.…”

“…At the same position, obvious colour mutation can be seen in both displacement contours, which means the fracture behaviour of this branch crack is shearing. When the crack encounters aggregate during crack development, the crack will stop developing and develop along the other weak surfaces of aggregate and cement matrix [ 45 ]. That is the cause of cracks branching.…”

A Review on the Applications of Acoustic Emission Technique in the Study of Stress Corrosion Cracking

“…The AE sources can be also classified in terms of RA value and average frequency (AF) in order to discriminate tensile and shear crack propagation [65][66][67]. This method evidenced effective results on corrosion degradation phenomena in steel reinforced concrete structures [68][69][70].…”