Strata movement and surface subsidence prediction model of deep backfilling mining

ABSTRACT

Surface subsidence prediction is an important approach to evaluate the surface damages caused by backfilling mining activities, and is applied to guide the recovery of coal resources under buildings, railways, and water bodies. With the mining depth increasing, the mining-induced stress and bedrock ratio increase, which lead to a different strata movement rule from shallow mining. Therefore, the appropriate surface subsidence prediction method for deep backfilling mining needs to be developed. To solve this issue, the coupled simulation method is employed to investigate the features of strata structure, strata movements, and internal strata movement boundary of deep backfilling mining. The simulation results show that the overburden is relatively integrated, and the subsidence of overburden is continuous. Compared with shallow mining, the curve of internal strata movement boundary of deep backfilling is more moderate, which is in accordance with an exponential function. Based on the simulation results, the strata movement prediction model of deep backfilling mining is established with the combination of elastic foundation theory and subsidence space conservation principle, and the prediction subsidence curve basically coincides with the simulation result. This model is highly instrumental in ground environmental protection.

KEYWORDS:

• Deep backfilling mining
• surface subsidence prediction
• mining damage assessment
• internal movement boundary of overlying strata
• coupled numerical simulation

Acknowledgments

We would like to acknowledge the support of the Jiangsu dual creative teams project awarded in 2017.

Additional information

Funding

This work was funded by the National Key Research and Development Program [Grant No. 2018YFC0604704; Natural Science Foundation of Jiangsu Province [Grant No. BK20180661; National Natural Science Foundation of China [Grant No. 51674249; China Postdoctoral Science Foundation [Grant No. 2019M660135; Fundamental Research Funds for the Central Universities [Grant No. 2018ZDPY05. 

Notes on contributors

Kaikai Guo

Kaikai Guo, He is currently a Ph.D student in School of Environment Science and Spatial Informatics, China University of Mining and Technology. His research interest is Mining Subsidence Control.

Guangli Guo

Guangli Guo, He is currently a Professor in  School of Environment Science and Spatial Informatics, China University of Mining and Technology. His research interests are Strata Movement Control  and Evaluation of Foundation Stability.

Huaizhan Li

Huaizhan Li, He is currently an Assistant Professor in School of Environment Science and Spatial Informatics, China University of Mining and Technology. His research interests are Strata Movement Control and Underground Coal Gasification.

Chenyang Wang

Chenyang Wang,  She received her master degree in China University of Mining and Technology. She is currently a teacher in Jiangsu Normal University Affiliated Experimental School. Her research interest is Spatial Information Managements.

Yaqiang Gong

Yaqiang Gong, He  received his Ph.D degree in China University of Mining and Technology.  His research interest is Mining Subsidence Control.