Issue 65

A. Namdar et alii, Frattura ed Integrità Strutturale, 65 (2023) 112-134; DOI: 10.3221/IGF-ESIS.65.09

Fig. 9 illustrates the displacement in the whole model after 1 second of applying seismic acceleration (g) to the model. The crack shows different morphology at each stage of the numerical simulation. The nature of the seismic acceleration (g) determines the failure mechanism in both models. In addition, the landfill clay cover thickness controls the crack propagation mechanism. With attention to the difference between lower and higher displacement levels in models 1 and 2, it seems that model 1 has a higher collapsing speed. Fig. 9 shows that the model's failure pattern occurs based on the model's lateral sliding. These similarities in the type of failure in models 1 and 2 occur due to the nature of the seismic acceleration. The compacted soil liner (CSL) needs to maintain a hydraulic conductivity of ( ≤ 1 × 10 − 7 cm/s). For this purpose, clay with a thickness in the range of 0.6–1.5 m is required [24–25], but from the seismic design perspective, the appropriate clay thickness needs to be recommended. Based on this analysis, it can be concluded that the landfill cover thickness needs to be designed to restrict landfill collapse and control leachate as well.

Important Vertical Peak Acceleration (g)

Vertical Peak Stress (MPa) 0.0013 -0.0017 -0.00195 -0.00157 0.00205 4.3911E-4 -0.00239 -0.00158 -0.00168 0.00166 0.00147 -0.00145 6.57155E-4

Vertical Displacement (mm)

Vertical Peak Strain

Initial crack length (mm)

No

1 2 3 4 5 6 7 8 9

-0.01317 0.01669 0.01484 -0.01374 -0.02729 0.02255 0.01522 -0.01426 0.01475 -0.01697 -0.01728 0.02336 -0.01757 0.01848 -0.02286 0.01837 0.01679 0.01536 -0.01761 0.01656 0.01925 -0.01507 -0.02218 -0.01928 0.01607 -0.02097 0.02514 -0.02796 0.0249 0.01613 0.016 0.0212

0

2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778 2778

0.26664 0.56451 -0.33746 -0.32985 0.30903 -0.35656 -0.40129 0.26985 -0.34188 -0.40806 0.33844 -0.52061 -0.37203 -0.39019 0.30296 -0.34633 0.28762 0.32446 -0.39414 -0.38885 0.30545 0.32431 0.56847 0.25819 0.26605 -0.34673 -0.40151 -0.39267 0.34885 -0.42581 -0.32551 -0.55136

-6.57439E-6 -3.985E-6 1.58766E-6 -4.85409E-6 -1.27384E-6 -8.50539E-6 3.63012E-6 -4.72572E-6 -3.00413E-6 -7.22713E-6 -4.9782E-6 2.68205E-6 2.82432E-6 -3.12113E-6 -1.99101E-5 -1.35034E-5 2.23796E-6 -4.34029E-6 -9.24661E-6 4.23915E-6 -3.49117E-6 -2.76953E-5 2.85844E-5 -1.92921E-6 -2.7582E-5 -1.40253E-5 2.64986E-5 -1.5879E-5 3.01826E-5 -2.90391E-5 1.00611E-5

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

0.00143 -0.00205 0.0018 0.00115 0.00142

-8.78402E-4 8.09171E-4

-0.00324 0.00297 0.00208

-4.41188E-4 -6.62765E-4

-0.00184 -0.00183 0.00202 0.00187

-8.60109E-4 -2.60599E-4

-0.00144

Table 3: Data used in ANNs for model 1 at node 4.

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