# Comprehensive Method to Test the Stability of High Bedding Rock Slope Subjected to Atomized Rain
## 5 Case Study
### Verification of Test Results with FEM
#### 5.8.2 Comparison Results of Comprehensive Method and FEM  
(1) Distribution characteristics of the displacement  
The model test and numerical calculation results all indicated that the maximum displacement was mainly concentrated at the upper and lower rock mass of C\({}_{3\text{-}1}\) and the exposed locations of the unloading cracks. The slope surface displacement was greater than the slope interior displacement. The displacement at the strengthened location was apparently less than that of the untreated location. The overall regularity of displacement tended to be consistent, and the numerical calculation results were slightly less than that of the model test. The displacement curves obtained by both methods showed a similar evolution process. At the initial cracking, various displacement curves began to show inflection points and fluctuation, and the surface displacement curves of the monitoring points at the exposed locations on C\({}_{3\text{-}1}\) and LS\({}_{337}\) showed a slight fluctuation. After the strength reduction by a factor of 1.2, the slope model was subjected to the steel frame lift. The displacement curves gradually increased and eventually showed a turning point. The increase in displacement became greater, and the slope showed a trend toward instability.  
Figure 17: Plastic failure process isoline of numerical calculation. (**a**) Under the self-weight; (**b**) \(K_{\text{P}}\) = 1.243 (with uplift 5\({}^{\circ}\)); (**c**) \(K_{\text{P}}\) = 1.512 (with uplift 10\({}^{\circ}\)).  
(2) Failure pattern  
From the global instability trend and regularity, the slope failure pattern tended to be consistent. In the model test, the exposed locations of the structural planes first cracked, the shear cracks on the bottom slip plane and tensile cracks on the cracked plane kept growing toward the interior of the rock, and cracks intermingled and penetrated to jointly form multiple slip blocks. When the slope finally failed due to instability, all the structural planes cracked and mutually penetrated, the surface of the rock was concentrated with cracks, and the rock showed an obvious trend of slip instability. Due to the concrete plugs, the crack-growing velocity of LS\({}_{337}\) was slow relative to C\({}_{3\text{-}1}\).  
In numerical calculations, the slope was primarily affected by the structural planes. Plastic failure first occurred on these structural planes. When the strength was reduced by a factor of 1.2, the two bottom slip planes and four cracked planes showed plastic failure, and apparent shear failure was observed on the bottom slip planes. With the increase of the uplift angle, the cracked plane was fractured by tension from the upper to the lower part. The plastic zones on the two bottom slip planes grew toward the interior and penetrated. When the slope finally failed, the plastic zones on various structural planes grew and penetrated, intersected with each other, and formed slip blocks and slip channel. Due to the concrete plugs, the plastic zone in the front edge of LS\({}_{337}\) was not penetrated. The failure pattern was consistent with the model test results.  
(3) Safety factor  
Comprehensive method: \(K_{\text{sc}}=1.526\text{-}1.576\)  
FEM method: \(K_{\text{sc}}=1.554\text{-}1.617\)  
Therefore, the calculation results were basically consistent with the model test results, and the comparison proved the reliability and feasibility of the model test.