In the heart of Beijing, researchers at the China University of Mining and Technology are unraveling the secrets of rock behavior under stress, and their findings could revolutionize tunnel blasting practices in the energy sector. Led by Xie Beijing, a team of scientists has delved into the dynamic splitting characteristics of water-saturated red sandstone, shedding light on how stress waves with varying pulse widths can induce or mitigate rock damage. Their work, published in the Journal of China University of Science and Technology (矿业科学学报), offers a glimpse into the future of safer, more efficient tunneling.
Tunnel blasting, a critical process in mining and infrastructure development, often triggers disasters like rock collapse. The key to mitigating these risks lies in understanding how different parameters of blasting stress waves affect the surrounding rock. Xie Beijing and his team have taken a significant step in this direction. “We found that the water-saturated condition can drastically weaken the strength of red sandstone,” Xie explains. “The tensile strength weakening rates were staggering—up to 95.09% in some cases.”
The team conducted dynamic Brazilian splitting tests using a split Hopkinson pressure bar system, a high-speed video camera, and digital imaging technology. Their experiments revealed that the damage mode of red sandstone is predominantly driven by the expansion of tensile cracks. “The increase of the pulse width of the incident stress wave can promote the initiation and expansion of these tensile cracks,” Xie notes. This insight could be a game-changer for the energy sector, where precise control over blasting parameters is crucial for maintaining structural integrity and safety.
One of the most intriguing findings was the role of moisture in energy absorption. “Moisture inhibits the absorption of energy in red sandstone,” Xie explains. “The absorbed energy per unit volume increases with the increase of the pulse width of the stress wave.” This discovery could lead to more efficient blasting techniques, reducing energy waste and enhancing safety.
The research also highlighted the importance of non-tensile energy consumption. Under certain conditions, the percentage of non-tensile energy consumption in water-saturated red sandstone was found to be higher than 80%. “When the impact speed is greater than 10 m/s, the energy consumption rate of red sandstone decreases to less than 5%,” Xie reveals. This could have significant implications for optimizing blasting practices in the energy sector.
The team’s work not only advances our understanding of rock mechanics but also paves the way for more sustainable and efficient tunneling practices. As the energy sector continues to expand, the need for safer and more precise blasting techniques becomes ever more critical. Xie Beijing’s research offers a promising path forward, one that could shape the future of tunneling and mining.
In the words of Xie Beijing, “Our findings provide a solid foundation for further research and practical applications. We hope that our work will contribute to the development of safer and more efficient tunneling practices in the energy sector.” With their groundbreaking research, Xie and his team are indeed making waves in the world of mining technology, offering a beacon of hope for a safer, more sustainable future.