Issue 62

S.Bouhiyadi et alii, Frattura ed Integrità Strutturale, 62 (2022) 634-659; DOI: 10.3221/IGF-ESIS.62.44

characterizes the behavior of the compressed earth block in the elastic phase 1 (Fig. 12). In the plastic regime, the response is generally characterized by strain hardening phase 2 (Fig. 12) followed by a softening by deformation beyond the ultimate strength phase 3 (Fig. 12). To determine the inelastic deformation of the point j of the "stress-strain" curve, it is necessary to draw the line parallel to the slope of the elastic phase and passing through the point j. The intersection of this line with the strain axis is the point of inelastic deformation in compression. To get the plastic deformation in compression we use the empirical equation below: We have      , , , c j in c j c j c E (8)

and



 , (1 ) c j

    pl c j c j , ,

(9)

c c E d

Then

      , c j pl

 d E d 1 c

(10)

, c j

, c j

c

c

or [17]



, c j

  1

d

(11)

c

 u

So

       , , ( c j in u c j E

  pl c j ,

1)

(12)

c

, c j

Figure 12: Stress-strain relation for compressive loading [19].

In Fig. 13, the last 4 stress-strain curves of compressed earth block solicited to a uniaxial load in compression present Young's modulus almost equal to 1700 MPa which is the initial proposal of our simulation, then a comparison between the experiment and the simulation must be between one of these tests. For our case, we choose the test 1-5. This curve presents the minimum ultimate stress   ,min ( 11.45 ) cu MPa compared to the selected tests.

645