**3. Experimental Setup**

The experimental schematic for the scabbling process of cement mortar is illustrated in Figure 1a. The laser source exploited in this study was ytterbium-pulsed fiber laser (IPG-YLPM, IPG photonics, model YLP-HP IPG photonics, Southbridge, MA, USA) with a wavelength of 1065 nm, the laser pulse duration of 30 ns, and laser spot size of 40 μm. This laser has a beam quality M<sup>2</sup> of 1.3. Furthermore, The F-theta lens are designed to focus the laser beam transmitted through fibers from a laser source. The focal distance from the F-Theta lens to scabbling area is 180 mm. In this study, the laser power was set at 180 W and 2 mm/s for scanning speed. In Table 3, the details of each parameter are presented. In addition, depending on dimension and minimizing the cracking of tested samples, the scabbled area was chosen 10 × 10 mm<sup>2</sup> (Figure 1b). To ensure that laser irradiation could cover the working area, the scabbling path was divided into two sections: (1) a square boundary line and (2) zigzag hatching lines. The pitch of the zigzag hatching lines was chosen at 0.05 mm to advance this scabbling method, as shown in Figure 1b.

**Figure 1.** (**a**) Experimental setup, (**b**) scabbling path (while (1) a square boundary line and (2) zigzag hatching lines).


