PSI - Issue 28

A. Saoud et al. / Procedia Structural Integrity 28 (2020) 491–501 Amal Saoud/ Structural Integrity Procedia 00 (2019) 000–000

494

4

2.3. Description of the prototype designed After several attempts and drawing inspiration from the various devices, we were led to choose the geometry that according to our study will give better results. This is shown in Fig 1, the dimensional characteristics of which are shown in Table 3.

Table 3: The different dimensions of the test piece

Symbol

Description

Dimensions (mm) accuracy of 0.1mm

W

Width

20 10 10 10

B E D L Z

Thickness

The width of the groove The depth of the groove

Length

234

The area of damage

20

a

Notch length Mooring area Mooring area

(4; 6; 8; 10;12)

A K

97

127

2.4. Description of the prototype of the 4ENF test piece The 4ENF (End-Notched Flexure) test is used for the study of break in straight slip mode (Mode II) which is intended to characterise the shear fracture of composite materials, this test piece was also used for the determination of wood toughness in Mode II. This test consists in flexing four points on a test piece containing an artificial defect on one of its sides. In reality, the mode of rupture in the ENF test is not perfectly pure mode II, the participation of mode I and mode III is present,

especially at the edges of the test piece and we notice a friction effect during the test The test is shown in Fig 2 and dimensional specifications are grouped in Table 4

Fig. 2. Schematic presentation of the 4ENF bending test