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Validation of the SIF values_
| S.No. | Variable verified (Dr) | 0.2 | 0.4 | 0.6 | 0.8 |
|---|---|---|---|---|---|
| 1. | Al Sanad (1993) [49] | 0.814 | 0.709 | 0.532 | 0.345 |
| 2. | Egorov (1965) [50] | 0.79 | 0.80 | 0.82 | 0.90 |
| 3. | Present analysis | 0.80 | 0.80 | 0.81 | 0.85 |
Shear stresses and its reduction due to the presence of an annular raft_
| Dr | Dg | Shear stresses of GPs without annular raft | Shear stresses of GPs with annular raft | Shear stresses reduction due to annular raft (%) | |||
|---|---|---|---|---|---|---|---|
| Top | Bottom | Top | Bottom | Top | Bottom | ||
| 0.2 | 2 | 2.324458 | 1.079298 | 0.123507 | 0.403755 | 94.70 | 62.65 |
| 3 | 2.232964 | 1.064219 | 0.107169 | 0.328567 | 95.20 | 69.17 | |
| 4 | 2.169796 | 0.974238 | 0.100482 | 0.263145 | 95.38 | 72.99 | |
| 5 | 2.134603 | 0.913877 | 0.084327 | 0.208937 | 96.06 | 77.21 | |
| 0.4 | 2 | 2.248837 | 1.079708 | 0.106494 | 0.349187 | 95.28 | 67.66 |
| 3 | 2.160045 | 0.957485 | 0.089982 | 0.261161 | 95.83 | 72.72 | |
| 4 | 2.120533 | 0.892764 | 0.074019 | 0.194048 | 96.51 | 78.26 | |
| 5 | 2.101452 | 0.876311 | 0.058483 | 0.145743 | 97.22 | 83.37 | |
| 0.6 | 2 | 2.147183 | 0.935131 | 0.087404 | 0.259689 | 95.93 | 72.23 |
| 3 | 2.103237 | 0.876795 | 0.063182 | 0.171468 | 97.00 | 80.44 | |
| 4 | 2.08833 | 0.886777 | 0.047783 | 0.11668 | 97.71 | 86.84 | |
| 5 | 2.082598 | 0.907918 | 0.03232 | 0.08452 | 98.45 | 90.69 | |
| 0.8 | 2 | 2.085437 | 0.895009 | 0.033402 | 0.132094 | 98.40 | 85.24 |
| 3 | 2.079723 | 0.934551 | 0.024073 | 0.080976 | 98.84 | 91.34 | |
| 4 | 2.079205 | 0.954441 | 0.020154 | 0.060053 | 99.03 | 93.71 | |
| 5 | 2.079428 | 0.963823 | 0.014868 | 0.047917 | 99.28 | 95.03 | |
Parameters used in the study_
| S. No. | Parameters | Corresponding values |
|---|---|---|
| 1. | Kgp | 10–400 |
| 2. | Dr | 0.2, 0.4, 0.6, 0.8 |
| 3. | Dg | 2, 3, 4, 5 |
| 4. | L/d | 5–40 |
| 5. | Np | 2–12 |