# BIM-Based Optimization of Drilling Angle and Hole Position of Outside Corner Anchor Rods
## 5 Conclusions  
This study has developed and improved traditional methods for the collision detection of foundation pit anchor rods using BIM technology and optimization technology. A BIM-based optimization method for anchor rod drilling in foundation pits was studied using visual programming software, achieving the following results:  
1. The program script runs in automatic mode in Dynamo, and digital sliders drive the inclination angle and hole position, updating the model data in real time. This method visually displays the collision situation of anchor rods and makes the optimization process visible;
2. The inclination angle optimization program script and hole position optimization program script are based on the anchor rod quality inspection standard in the \"Code for Acceptance of Construction Quality of Building Foundation\" (GB 50202-2018). The drilling inclination angle and hole position are \(\leq\)3\({}^{\circ}\) and \(\leq\)100 mm, respectively, meeting construction quality acceptance standards. This method ensures the authenticity of the results when compared to traditional methods;
3. The input precision during the optimization process is not limited by the script program and can be adjusted according to actual needs and the equipment used, ensuring the accuracy of the results;
4. The program script runs in automatic mode in Dynamo, and compared with traditional manual adjustment, it can quickly complete a large number of anchor rod collision detections and drilling optimizations, thereby saving costs;
5. By optimizing the inclination angle and hole position of anchor rods at the foundation pit's outside corner in advance within the design information and national standard error tolerance range, the accurate range value interval can be obtained, effectively reducing the number of anchor rod collision points at the outside corner. After optimization, the collision situation disappears, ensuring the safety and stability of the foundation pit support system.  
The results obtained using this method can guide construction, ensuring the safety and stability of the foundation pit support system and providing a reference for solving the problem of anchor rod collision at the outside corner of foundation pits.  
Due to the research progress limitations, the drilling optimization script program is divided into the optimization of hole position and inclination angle, and there is still room for improvement with regard to time consumption. Further algorithm optimization is needed to combine the two scripts into one, making the program more intelligent and efficient.  
Conceptualization, Z.J. and X.Z.; methodology, Z.J., D.L. and X.Z.; software, D.L.; validation, D.L., X.Z. and Z.J.; formal analysis, D.L. and X.Z.; investigation, X.Z.; resources, D.L., Z.S. and W.L.; data curation, D.L.; writing--original draft preparation, Z.J., D.L. and X.Z.; writing--review and editing, Z.J., Z.S. and W.L.; visualization, D.L. and Z.J.; supervision, X.Z.; project administration, X.Z., Z.S. and W.L. All authors have read and agreed to the published version of the manuscript.  
This research was funded by Research and practice of multiscale coupling of building information and regional information, grant number 2017-R3-005.  
Not applicable.  
The authors wish to gratefully acknowledge the co-workers at Beijing Huazhu Building Science Research Institute Co., Ltd. for their help during this study. The authors would also like to thank the editors and the anonymous reviewers who presented critical and constructive comments for the improvement of this paper.  
The authors declare no conflict of interest.