# Payment Structure Characteristics and Behaviour Analysis with Digital Image Correlation
## 1 Introduction
The visual method enabled the definition of the crack progression path, which was detected along the length of the geosynthetics used for reinforcement, and classified it as a weak zone in the structure [19]. Besides asphalt pavements, the DIC technology can also be used in concrete pavement analysis. Several research projects have dealt with monitoring the fracture mechanism of concretes by DIC [20; 21; 22; 23; 24; 25; 26]. [PERSON] [20; 21] precisely traced the development of intra-material cracks in concrete made of quaternary binders exposed to fracture toughness tests. Additionally, the same author developed a new method for the determination of the actual crack path length during a shear test conducted on concrete specimens and monitored by DIC [22], proving the suitability of the method for the determination of the fracture toughness of concrete specimens [23]. [PERSON] et al. [24] determined a critical opening displacement of a concrete specimen by the Bazant Crack Band Model, which was followed by the use of the DIC method for defining the displacement fields on the concrete specimen surface. [PERSON] et al. [25] used DIC methods for the analysis of the fracture mechanisms and fracture characteristic parameters during three-point bending tests. [PERSON] and [PERSON] [26] categorised the DIC method as effective for monitoring displacement and crack length due to fracture testing. The DIC technology was also used in evaluating the sensitivity of concrete to elevated and low temperatures. Thus, this method was used in [27] to monitor the propagation of cracks in concrete exposed to elevated temperatures and, in [28], in concrete exposed to low temperatures. It should be pointed out that in the research presented in [28], the 3D-DIC technology was used, and the satisfactory matching of the crack propagation paths detected by the 3D-DIC method with the actual situation was highlighted; in the research presented in [27], 2D-DIC was used, and as such, it was assessed as suitable for monitoring crack propagation. [PERSON] and [PERSON] [29] emphasised the potential of 3D-DIC as a replacement for conventional tools for strain determination due to it providing rich data for analysis. Furthermore, the suitability of the method for establishing the stress and strain curve during the compression test was highlighted [27; 30]. The DIC technology has also proven to be useful in this area in combination with the strain gauge measurement system. The advantage of this procedure means the possibility of monitoring the crack development caused by the expansion of the reinforcing element due to corrosion [31]. Due to the lack of a standard procedure for the optimisation of the 2D-DIC parameters, [PERSON] et al. [32] established parameters for concrete structures at three accuracy levels, which can be used as a source of reference in concrete testing. Besides laboratory testing, the DIC technology can be used even on structural members. Thus, [PERSON] et al. [33] used the DIC technology in combination with the Daubechies wavelet when testing concrete beams. The suitability of this approach was highlighted; as disadvantages, they cited the impossibility of conducting such a test on very large structures such as bridges and dams, and they also pointed out the problem of the impossibility of using artificial light on such structures. The DIC technology found its place, also, in pervious concrete testing for pavement application. In their work, [PERSON] et al. [34] used DIC for crack generation and propagation detection in geogrid-reinforced pervious concrete. Furthermore, this technique was used to monitor crack development based on a cylindrical specimen of cement-stabilised material with steel fibres during indirect tensile loading. As a result, the CAD tool captured pictures to estimate the crack lengths [35]. The possible combination of the DIC with a scanning electron microscope (SEM) was also encouraged in [36].