In order to study the present state of the tectonic stress field in northwest Jiaodong Peninsula, the characteristics of the ground stress distribution along depth were analyzed with the method of regression analysis. A total of 164 items of in situ stress measurement data were collected. There are mainly two types of in situ stress states, one is σ_H>σ_h>σ_v and the other is σ_>σ_v >σ_h, and the type of in situ stress state is related to the depth. The principal stresses σ_H, σ_h, and σ_v increase approximately linearly with depth, and the stress gradients are 0.0556, 0.0248, and 0.0346, respectively. The lateral pressure coefficients KH, Kh, and Kav vary approximately hyperbolically with the increase in depth and approach 1.99, 1.12, and 1.56, respectively. The ratio of half of the maximum horizontal differential stress to the average horizontal principal stress μ_d varies linearly with the increase of depth and approaches the value of 0.33. The maximum shear stress τ_m increases approximately linearly with depth, and the stress gradients are 0.0146. The ratio of horizontal principal stress difference with vertical stress on 1000 m–2000 m is 0.5– 0.7. In addition, the maximum level of principal stress advantage direction in the northwest Jiaodong Peninsula is nearly E–W.

The management of rock mass deformation in high-stress roadways is a pivotal aspect of deep geotechnical engineering. Given the fruitful outcomes of research in rock mechanics regarding traditional confining pressure control methods, scholars have increasingly turned their attention to exploring pressure-relieving techniques, including borehole pressure relief and blasting pressure relief. However, there is limited research on pressure relief methods for deep-buried hard rock tunnels. This article commences with an overview of pressure relief in the roadway and conducts a detailed study on the parameters and methods of pressure relief in the roadway. To address safety and mining efficiency challenges, such as severe deformation leading to support failures, this study conducted a parameter analysis using the Sanshandao Gold Mine as a case study. Based on existing support methods, a strategy for arranging pressure relief roadways at varying distances from the main roadway is proposed, significantly enhancing the stress environment there. Numerical simulation software was employed to model two scenarios: (1) excavating the pressure relief roadway, main roadway, and maintenance roadway simultaneously and (2) first excavating the pressure relief roadway, followed by the main roadway and the maintenance roadway simultaneously. Simulation results indicated that the first pressure relief approach outperforms the second. The optimal position for both pressure relief roadways is 15 m from the main roadway, resulting in maximum deformation of the main roadway within 100 mm. These findings align with on-site stress monitoring data and satisfy safety production criteria. The research offers a theoretical foundation for similar pressure relief techniques in deeply buried, high-stress roadways.

Increasing construction depth, changeable failure formations, and redistributed stress conditions inevitably make the mechanical response of mining shaft rock mass complicated. The design method and construction technology of deep shaft need to be perfected urgently. We studied the stability and control method of a main shaft from −930 m located in a deep gold mine. It is concluded that the surrounding rock of the shaft faces conditions including non-high-stressed, high-stressed, and possible instabilities. The failure types include structural plane-controlled failure, deep stress induced failure, rock burst, low confining pressure shear failure, spalling, and frequent conversion of multiple failure. The damages of the surrounding rock mass at −930~−1500 m displayed “ear-shaped” damage, with damage ranges of less than 2.5 m. The shaft temporary reinforcement adopted bolt mResh beam support, in which the length of the bolt was 2.5~3 m, and the row spacing was 1.5 m. The steel type and diameter were determined by the on-site bolt pull test. This temporary support countermeasure plays an important role in preventing shaft deformation and is worth promoting in similar mines.

In order to solve the problem that the broken rock mass is easy to collapse and fall during the excavation of a submarine gold mine, two kinds of bolt-mesh-concreting combined support schemes are designed by means of field engineering geological investigation, indoor rock mechanics test, rock mass quality classification, and theoretical analysis. We use the numerical simulation for verification and carry out the field industrial test. The results show that the stability grade of broken surrounding rock is III–IV; both schemes can effectively control the deformation and failure of surrounding rock. Compared with the unsupported scheme, the maximum roof displacement in the scheme using roadway roof and sidewall support is reduced by 26.9%, the maximum thickness of the roof plastic zone is reduced by 58.2%, and the volume of the surrounding rock plastic zone is reduced by 26.32%. The bolt-mesh-shotcrete support has good control effect on the loose deformation of surrounding rock, which can effectively prevent the roof collapse and sidewall spalling of roadway. The field industrial test of support scheme meets the stability control requirements of broken rock mass in mines, and the application effect is obvious. The research results presented in this study provide valuable technical guidance and essential insights for the design of support systems in other similar mining projects, contributing to the effective control and stability of broken rock masses during excavation.