## 6 Conclusions  
This paper, based on practical engineering, focuses on the movement and ejection of rock mass during underground mining blasts. A FEM-SPH numerical model was constructed through three-dimensional modeling, and LS-DYNA numerical simulation software was employed to investigate the movement patterns of rock mass under precise delay blasting in underground environments. The study aimed to explore the spatiotemporal evolution of rock mass movement post-blasting and verify the influence mechanism of precise delay times on rock mass movement patterns through comparative field blasting experiments. The dynamic response characteristics of rock mass movement after underground access stope blasting were revealed through precise delay initiation using digital electronic detonators under 25 ms, 50 ms, and 75 ms delay conditions.  
Numerical simulations of multi-row borehole blasting using the SPH method revealed the movement characteristics of rock mass. The results indicated that within a certain delay time range, the ejection distance of rock mass increased with increasing inter-row delay time, exhibiting a pattern where the accumulation was concentrated near the excavation face and dispersed towards the farther end.  
Research on rock mass movement patterns under different delay times showed that at 25 ms and 50 ms delays, due to the short inter-row delay, the rock mass already affected by the explosion could not be effectively ejected to the free face during the delay period, resulting in significant restraint and inhibiting the creation of new free faces, which could lead to poor blasting outcomes. At 75 ms delay, the blasting effect could effectively eject the rock mass during the inter-row delay period, creating new free faces and providing effective compensation space for subsequent blasting, which had a beneficial impact on the blasting outcome.  
Studies on the spatiotemporal evolution of rock mass movement under different delay times revealed that the pile morphology was significantly influenced by the delay time. Within a certain delay time range, the slope angle of the pile decreased with increasing inter-row delay time. Blasting piles with shorter inter-row delays were steeper, while those with longer inter-row delays were gentler.  
Conceptualization, H.C. and J.Z.; methodology, H.C. and G.W.; software, G.W. and J.Z.; validation, H.C. and G.W.; formal analysis, J.Z. and H.C.; investigation, J.Z. and H.C.; resources, G.W. and H.C.; data curation, J.Z. and G.W.; writing--original draft preparation, J.Z. and G.W.; writing--review and editing, [PERSON] and J.Z.; visualization, J.Z. and H.C.; supervision, [PERSON] and J.Z.; project administration, G.W. and J.Z. All authors have read and agreed to the published version of the manuscript.  
Tanshan Talent Project of Xinjiang Uygur Autonomous Region (2023 TSYCCX0095).  
Not applicable.  
Data Availability Statement: Data is contained within the article.  
We are grateful to the anonymous reviewers for their insightful and constructive comments for improving the manuscript.  
Author [PERSON] was employed by the company Xinjiang Kalatongke Mining Corporation Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.