Abstract

Coal mine waste rock can be filled into the gob to control strata movement and protect the mine environment. However, the compaction behaviour of the waste rock backfill materials (WRBM) must be considered when the they are filled into the coal mine gob. Based on the compaction properties of the WRBM tested by a purpose-made compaction device, Salamon's and Terzaghi's models are used to describe the stress–strain relationship of the WRBM, and the parameters updating (PU) and calibrated double-yield model (CDM) methods to simulate the WRBM are proposed in this paper. An engineering application in a backfill panel is used to validate the reliability of this method by numerical simulation and field measurement. Comparison of the vertical stress inside the WRBM obtained by the numerical simulation using the proposed method with those from field measurement indicates that the proposed method is reliable. The proposed method gives an opportunity to obtain the stress distribution accurately when the WRBM are filled into the coal mine gob.