High-speed photography for fracture studies of concrete

Experimental Investigations of Fracture Process Using DIC in Plain and Reinforced Concrete Beams under Bending

“…A direct observation of fracture is difficult because of a small scale at which micro‐structural events interact with a failure process. Different techniques have been used up to now to experimentally investigate a fracture process in quasi‐brittle materials (concrete, rock and masonry) at the laboratory scale such as scanning electron microscopy (SEM) , high‐speed photography , laser speckle interferometry , acoustic emission technique , X‐rays and digital image correlation technique . Recently, the most popular method (due to its availability, simplicity and low cost) has become the digital image correlation (DIC) technique, which is an optical and a non‐contact measurement method to visualize surface displacements—obtained by tracking the deformation of a random speckle pattern applied to the surface through digital images acquired at different instances of deformation.…”

Use of Scanning Electron Microscope and the Non-local Isotropic Damage Model to Investigate Fracture Process Zone in Notched Concrete Beams

“…-The direct techniques: based on an attempt to observe the material directly: high-speed photography [6], scanning electron microscope [10, 18-20, 27, 28]. -The indirect techniques: based on indirect observations: embedded graphite rods [14], dye penetration 29], infrared vibrothermography [7], ultrasonic measurement [25], laser speckle interferometer [1], acoustic emission technique [16,17,24,25].…”

Fracture Mechanics of Concrete – State-of-the-Art Review

“…The FPZ has a capability to still transfer the closing stress across the crack faces which decreases at increasing deformation as shown in Fig. 2 (Derucher 1978), scanning electron microscopy Diamond 1980, 1982), and high-speed photography (Bhargava and Rehnström 1975), whereas the indirect methods are laser speckle interferometry (Ansari 1989), compliance and multicutting techniques (Hu and Wittmann 1990), penetrating dyes (Lee et al 1981), ultrasonic measurement (Sakata and Ohtsu, 1995), infrared vibro-thermography (Dhir and Sangha 1974), and acoustic emission technique (Maji and Shah 1988, Maji et al 1990, Ouyang et al 1991, Hadjab et al 2007). The typical size of FPZ is in the order of 50 cm for normal concrete, 3 m for concrete dam with extra large aggregate, 10 m for a grouted soil mass, and 50 m for a mountain with jointed rock.…”