In the heart of China’s Jiangsu Province, researchers at the School of Physics and New Energy, Xuzhou University of Technology, are unraveling the mysteries of cemented backfill, a critical component in the stability of mine structures. Led by Peng Wu, a team of scientists has published groundbreaking research in the journal *Case Studies in Construction Materials*, translated from Chinese as “Case Studies in Construction Materials,” that could significantly impact the energy sector’s approach to mine backfill design and assessment.
The study focuses on the influence of curing temperature on the creep properties of alkali-activated slag-loess-based cemented backfill (SLCB), a material widely used in mine backfilling. Creep, the tendency of materials to deform under constant stress, is a crucial factor in the long-term stability of mine structures. By understanding and predicting creep behavior, engineers can design more robust and safer backfill structures, particularly in high-temperature environments.
The researchers conducted triaxial step-loading creep tests on SLCB specimens subjected to various curing temperatures, ranging from 5°C to 50°C. Their findings reveal that curing temperature significantly influences the creep behavior of SLCB. As the temperature increased, the total creep duration extended, the critical stress threshold was elevated, and creep resistance was enhanced.
“Our results indicate that the creep behavior of SLCB exhibits typical three-stage characteristics—deceleration, steady-state, and acceleration,” Wu explained. “As the temperature increased from 5°C to 50°C, the total creep duration extended by a factor of 2.58, and both instantaneous strain and extreme creep strain decreased linearly with increasing temperature.”
The team also developed a nonlinear viscoelastic-plastic creep model incorporating temperature effects, based on fractional-order calculus theory. This model demonstrates high-precision fitting of the full-stage creep curves across different temperatures and effectively characterizes the coupling effects of temperature, stress, and time.
The implications of this research are substantial for the energy sector. By providing a theoretical basis for evaluating the long-term stability of mine backfill structures, this study offers critical guidance for the design and assessment of backfill structures subjected to high-temperature environments. This could lead to more efficient and safer mining operations, reducing the risk of structural failures and enhancing the overall productivity of mines.
Moreover, the developed fractional-order creep model can be a valuable tool for engineers and researchers, enabling them to predict the behavior of SLCB under various conditions accurately. This predictive capability is crucial for optimizing the design of backfill structures and ensuring their long-term stability.
As the energy sector continues to evolve, the demand for robust and efficient backfill materials will only grow. This research by Wu and his team at Xuzhou University of Technology represents a significant step forward in meeting this demand, providing valuable insights and tools for the design and assessment of mine backfill structures.
In the words of Wu, “Our findings provide critical guidance for the design and assessment of backfill structures subjected to high-temperature environments, shaping future developments in the field and contributing to the safety and efficiency of mining operations.”