## 4 Results
### Site Response  
Figure 14 shows the surrounding ground settlement after the excavation of 6.7 m. It is obvious that the ground settlement along the foundation pit wall is distributed as a gradual decrease from the middle to the sides with a bulge at the corner of the foundation pit, indicating a significant spatial effect. Meanwhile, the ground settlement on the east side of the foundation pit is smaller than the other three areas, which means that the presence of adjacent existing buildings on the east side has a certain impact on ground settlement. Thus, the pit wall was divided into seven different segments and numbered clockwise according to I to VII; then, seven monitoring sections perpendicular to wall were set in the middle of segments, numbered as I-I, II-II, III-III, IV-IV, V-V, VI-VI, and VII-VII, as shown in Figure 1.  
Figure 14: Cloud map of surrounding ground settlement when the excavated depth is 6.7 m.  
Figure 13: Bending moment contour maps of the roof of the first underground floor. (**a**) The X-direction; (**b**) the Y-direction.  
Figure 15 presents the ground settlement troughs of seven monitoring sections during the construction process. As the construction progresses, the settlement continues to increase. From Figure 15, it can be seen that there is uplift deformation near the pit wall, the ground settlement curve shows a clear groove shape, and the settlement reaches its maximum at a distance of about 2.0-3.0 m from the pit wall. Due to the existing residential buildings on the east of the pit, the settlements of monitoring section III-III and section IV-IV increase as the distance from the pit wall increases after exceeding 11.0 m. That of the other monitoring sections are different, manifested as the ground settlements being basically the same, with a slight decrease after the distance from the pit wall exceeding 10.0 m. The construction of process 10 has a relatively minimal impact on the ground settlement, and all the construction processes have no impact on the position of the maximum deformation value of the ground settlement trough. After the completion of construction, the maximum settlement value reaches 13.8 mm, and the maximum uplift value reaches 4.8 mm, both of which are far less than the design control value (30.0 mm), meeting the safety requirements. From Figure 15, the maximum settlement for all sections are approximately between 0.11% \(H\) and 0.54% \(H\) (\(H\) is the excavation depth of the pit), and the influence range of excavation is between around 0.88 \(H\) and 1.37 \(H\), which indicates that the spatial position of the diaphragm wall, the wall length, and the spatial position of existing buildings have a significant impact on the magnitude and the shape of the settlement trough but have little impact on the location of the maximum settlement in the settlement trough. The distribution of the settlement trough indicates that the significant impact range of excavation of the pit in this project is approximately within 10.0 m around the pit. Therefore, it is necessary to strengthen the monitoring of the structures and traffic routes within 10.0 m around the pit to avoid the adverse impact of construction during excavation.  
Figure 15: \(Cont.\)  
Figure 16 shows the horizontal displacement of strata behind the wall at different monitoring sections after the completion of construction. It is observed that the strata behind the wall have a horizontal displacement towards the pit, and the deformation characteristics are quite similar to that of the diaphragm wall, also showing the shape of \"double peaks\", and the deformation values are basically the same, indicating that the deformation of the pit was in a stable state. With the increase in the extension length of the diaphragm wall, the horizontal displacement of strata behind the wall gradually increases, but the maximum displacement always appears around 22.5 m below the ground. The maximum horizontal displacement is about 1.4-2.0 times that of the ground.