*2.3. Equipment and Tools*

The Tinius Olsen press that was used is computer-controlled with software from Horizon. The measurement frame includes two movement sensors on each side of the beam fastened on the frame, in accordance with ÍST EN 14488-3: 2006. See Figures 3 and 4.

**Figure 3.** The measuring frame. 1. The steel frame; 2.. Movement sensors on each side. Independent of the load; 3. Load points; 4. The steel frame; 5. Movement sensors for the beam; 6. Free swing bolts; 7. Supports.

**Figure 4.** The set-up according to the IST EN 14488-3: 2006.

### *2.4. Installation and Implementation*

Installation and implementation were in accordance with the standard IST EN 14488-3: 2006 and Guidance from ACI no. 544.4R-18. Beams were all constructed in the same form, 150 × 150 × 600 mm. Deviations were ±5 mm in length. Hardly any deviation was found in the height or width. In Figure 5 is a profile as shown in the IST EN 14488-3: 2006, d = 150 mm, w = 150 mm, L = 600 mm.

**Figure 5.** The actual setup.

The procedure of the experiment was as follows:


The cracking occurred in all cases from the bottom of the beam and upward, between the load points (rolls). From that, it is easy to recognize that this was a moment of failure in all cases. From that, the conclusion can be made that all tests are valid.

The Basalttex fibers were difficult to see in the fractured concrete but the Reforcetech fibers were more noticeable. Shown in Figure 6.

**Figure 6.** Reforcetech fibers are visible in the fracture but Basalttex fibers are less visible.

### **3. Results**

After each execution, a cvs log file was created. It showed the load, the movement of the beam from the beginning of the test, movement speed, time and the two movement sensors. From each datafile, a graph was extracted for a visual comparison. The calculations were as follows Formula (1): The total average displacement was calculated using the two displacement sensors on the press, where *d*1 is the reading on displacement sensor 1 and *d*2 is the reading on displacement sensor 2. The *d*10 and *d*20 are the set displacements at the beginning of the test.

$$d\_{tot} = \frac{\left((d1 - d2\_0) + (d2 - d2\_0)\right)}{2} \tag{1}$$

Each flexural strength was calculated as an equivalent elastic tensile strength: flexural strength in MPa = P × l/(w × d2) where:


As previously stated, the log file automatically ran until the entry of the load source was 5 mm. The entry standard 14488-3: 2006 includes variable speed. Firstly 5 mm/min up to 250 N, then 0.25 mm/min until the post was 1mm long. After that, 1 mm/min until the load sourceshift reached 5mm.

**Figure 7.** Methodology of defining the load Pfp from IST EN 14488-3: 2006.
