Why the Yushenfu Mining Area's Geology Demands New Crack Prediction Approach

By Dr. Noopur JainReviewed by Laura ThomsonApr 2 2025

In a recent article published in Scientific Reports, researchers addressed the critical issue of mining-induced surface cracks within the Yushenfu mining area, a region noted for its ecological vulnerability and strategic significance in coal production for China's energy security.

This area's unique geological and climatic conditions make it susceptible to severe geological hazards, particularly surface cracks that threaten the fragile ecosystem and local communities. Given the disruptions caused by large-scale coal mining activities, there is an urgent need for effective prediction methods to accurately identify surface cracks' formation mechanisms.

This research aims to refine existing predictive models by optimizing a formula for horizontal deformation, thereby enhancing the understanding and prediction of mining-induced geological imperfections.

Background

The Yushenfu mining area is located at the Mu Us Desert and the Loess Plateau interface, characterized by alternating layers of loess and aeolian sand.

This region experiences significant climatic variations, with a yearly average rainfall of 400 to 450 mm, predominantly occurring during the summer months.

Such unique environmental conditions and intensive coal mining practices have resulted in numerous geological challenges, particularly mining-induced surface cracks. These cracks arise from stress redistribution and structural failures during coal extraction, creating a progressive geomechanical phenomenon.

Prior research has explored the parameters impacting these cracks, including mining conditions and the physical movements of geological strata. However, the distinctive conditions of the Yushenfu mining area necessitate tailored prediction methods.

The study presents an innovative approach that incorporates a variety of technical methodologies, including elastic and soil mechanics, as well as numerical simulations to develop a comprehensive prediction method for cracks influenced by the area's unique features.

The Current Study

To predict the location and depth of surface cracks, the study established an elevated prediction method that utilizes horizontal deformation as its central parameter. The research combined various technical aspects, specifically focusing on the mechanical properties of the surface loose layers in the Yushenfu mining area.

The team built a mechanical model to analyze the wedge-shaped loose layer, carefully accounting for factors such as the influence of seasonal rainfall on soil strength properties.

The prediction method incorporates a comprehensive model representing the stress distribution within the loose layers during coal extraction, particularly tailored to analyze rainy and dry seasons.

The study examined the intricate relationships between horizontal deformation, subsidence, and crack formation mechanisms by employing numerical simulations alongside physical similarity methods. To ensure the predictive model's robustness, a wide array of mining parameters, including the characteristics of specific coal seams and the overlying strata, were monitored.

The framework also systematically evaluates the key parameters of horizontal deformation during the two identifiable stages of the Active Phase of the subsidence process.

Results and Discussion

The study results highlight the efficacy of the optimized prediction method. It showcased superior performance compared to traditional predictive calculations when forecasting the locations and depths of mining-induced surface cracks.

Through detailed observations and data collection at the 112201 working face, the research revealed that boundary cracks were concentrated within a "belt area," between 18 to 56 meters outside the roadway, with depths varying from 0.45 to 2.32 meters.

The theoretical predictions concurred with these observed dimensions, establishing a strong correlation between predicted and actual measurements.

Notably, the findings indicated that cracks were expected to form between 8.05 meters outside and 48.73 meters inside the roadway during non-rainy seasons.

Conversely, predicted crack locations shifted slightly during the rainy season to 14.82 meters outside and 50.16 meters inside. The research demonstrated that seasonal variations impacted further crack depth, with shallower cracks occurring during rainy periods due to the moisture's influence on soil strength.

The combination of physical simulation, numerical simulation, and theoretical calculations provided a multifaceted perspective on the relationship between mining activities and surface crack development.

Critical horizontal deformation peaks, especially exceeding the soil's ultimate tensile strain, proved to be pivotal factors in crack formation. Moreover, the optimization of the prediction model integrated various modern techniques, reflecting an improved accuracy rate in forecasting crack development that had been relatively low in traditional methodologies.

Conclusion

This study advances the field of mining subsidence prediction by introducing an innovative approach tailored to the unique geological and climatic conditions of the Yushenfu mining area.

The application of refined prediction equations for horizontal surface deformation successfully delineates the correlation between mining activities and crack formation.

The findings confirm that the prediction method effectively estimates the location and depth of surface cracks and offers an enhanced understanding of the processes leading to their development.

By addressing the complexities of the area's environmental conditions and incorporating extensive data from field observations, the study presents a robust framework that can significantly mitigate the environmental impacts of mining activities.

This research paves the way for future studies focused on developing sustainable mining practices that harmonize with ecological preservation in sensitive regions like Yushenfu.