Controlled Creating of Cracks in Concrete for Non-destructive Testing

Abstract

The non-destructive assessment of cracks in concrete is a common task for which non-destructive evaluation solutions have been published. Primarily, these tests have been carried out on artificial cracks that have been created by using notches instead of natural cracks. This study evaluates a procedure designed to create reproducible and controlled cracks in concrete. The procedure is based on using expanding mortar in a series of blind holes. This is done in combination with carefully aligned reinforcement to guide the direction of the crack development. The depth of the crack is also controlled by reinforcement. Crack depth varies statistically in the range of the maximum aggregate size (16 mm) used for concrete.

Evaluation of retroreflective corner echo for detection of surface breaking cracks in concrete by ultrasound

“…The measurement and evaluation procedure was developed using concrete specimens with the dimensions 1.5 m × 0.6 m × 0.25 m (length × width × thickness) with notches and cracks initiated under controlled conditions [13]. Line-scans and area scans with scanning direction perpendicular to the crack line were acquired on the top surface of the blocks using the linear array A1040 Mira (Acoustic Control Systems, ACS).…”

“…The top surface of one specimen was first measured in intact state without defect. Afterwards a separating crack was generated using the method described in [13]. To confirm that the crack completely penetrated the specimen, it was turned to inspect the back surface, where the crack was visible over its full width.…”

Analysis of up-to-date methods of non-destructive testing of performance properties of reinforced concrete building structures

“…Further, the principle of the device operation is similar to the method of detachment with chipping. Despite the widespread application of the given method in foreign countries [4,5], it is used less frequently in Russia. This is due to disadvantages, in particular, related to the dependence of adhesive composition on temperature and humidity conditions, the density of its application to the disk, etc.…”

Elastic immersive wave experimentation

“…Recomputing the full wavefield while performing only local wavefield simulations on a sub-domain that encloses the model alterations would significantly reduce the required computational resources, so this has been an active area of research in exploration geophysics and seismology (e.g., Lin et al, 2019;Jaimes-Osorio et al, 2021;Aaker et al, 2020;Pienkowska et al, 2020). Local-domain modeling can also be applied for investigating a target of interest inside a sub-volume of a medium, for example, in nondestructive testing where damage zones are commonly highly localized (e.g., fracture corridors, see Nosjean et al, 2020;Zerbst et al, 2016;Wiggenhauser et al, 2018), in medical acoustics where modeling targets are often local organs such as a beating artery or liver fat (e.g., Kyriakou, 2015;Solovchuk et al, 2015;Robertson et al, 2017), and in modeling of electromagnetic waves such as for ground-penetrating radar (GPR) which are often used to detect a local target in the Earth's subsurface (Lambot et al, 2004;Hartley et al, 2018;Akinsunmade et al, 2019). Particularly for imaging and inversion in all of these fields (e.g., Guyer & Johnson, 2009;Duan et al, 2017;Beach & Dunmire, 2007;Mari & Mendes, 2012;Ning & Sava, 2019;Wang et al, 2020), local-domain simulations may be useful to save computational cost compared to simulating full models.…”