# Centrifuge Modelling of the Impact of Excavation with Partition Piles on Adjacent Existing Tunnel
## 4 Summary and Conclusions  
This study delved into the impacts of pile length and the top burial depth of piles on tunnel deformation induced by excavation, employing partition piles in two-dimensional centrifuge simulation tests. The primary findings can be summarized as follows:  
Figure 12: Convergence deformation of tunnel.  
Figure 13: Induced strain in circular direction of existing tunnel.  
1. The horizontal displacement of the retaining wall exhibited a cantilever-type displacement. In the control group, The horizontal displacement at the wall's top section was approximately 1.04% times the excavation depth. After adding partition piles, the maximum horizontal displacement decreased by up to 10.6%.
2. The ground settlement behind the wall exhibited its maximum intensity in the immediate proximity to the retaining wall, gradually diminishing with the increasing distance from the retaining structure. In the control group, the maximum ground settlement reached 1.1% times the excavation depth. The addition of partition piles reduced ground settlement near the wall by up to 40.1%.
3. The complete deformation of the tunnel exhibited an approximate horizontal elliptical distortion, where the greatest horizontal displacement transpired at the right shoulder of the tunnel, and the maximum vertical displacement unfolded at the right arch of the tunnel. The introduction of partition piles resulted in a 36.7% reduction in the maximum horizontal displacement and a 31.8% decrease in the maximum vertical displacement of the tunnel.
4. The impact of partition pile parameters on the control efficacy of retaining wall displacement, ground surface settlement, and tunnel rigid displacement was broadly consistent. Increasing the length of the piles led to a deterioration of the control effect. The control effectiveness of partition piles could be further enhanced by increasing the top burial depth of the piles, but when it was too large and exceeded its critical value, the improvement effect of the top burial depth of piles on partition piles diminished.
5. In view of the effectiveness of the partition pile in controlling tunnel deformation mentioned above, further research should be conducted to optimize the control effect of the partition pile. Finding the optimal solution of the top burial depth of the pile in the subsequent studies will be a key direction. This will facilitate a deeper exploration of the mechanisms underlying the deformation control effects of partition piles concerning pile length and top burial depth of the pile. Subsequently, numerical simulations will be conducted to draw the deformation control zones of partition piles under various conditions. It will have positive implications for future excavation projects near existing tunnels.  
Conceptualization, Y.D. ([PERSON]); methodology, Y.D. ([PERSON]), B.W. and Y.D. ([PERSON]); software, B.W., H.Z., Y.S. and X.Z.; investigation, Y.D. ([PERSON]) and B.W.; data curation, B.W.; writing--original draft preparation, Y.D. ([PERSON]); writing--review and editing, B.W. and Y.D. ([PERSON]); funding acquisition, Y.D. ([PERSON]). All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Natural Science Foundation of China (grant number: 52008293).  
Not applicable.  
Data Availability Statement: Data are contained within the article.  
The authors declare no conflict of interest.