Sediment settlement rate and consolidation time of filling reclamation in coal mining subsidence land

With the continuous growth of the population and the continuous reduction of cultivated land, China’s food security is greatly threatened. In addition, China’s coal mining has been mainly underground mining, causing land subsidence and damaging existing cultivated land. This effect intensifies the contradiction between the growth of the risk population and the reduction of cultivated land. The reclamation of mining subsidence land with Yellow River sediment is often used as an effective way to improve the recovery rate of cultivated land. Shortening the reclamation time and realizing continuous filling are significant issues. The work presented in this paper studied the sediment settlement rate and consolidation time by combining theory, field filling and reclamation tests and numerical simulations. A field filling test study was carried out in the lowlands of Jibeiwang Village, Qihe County, Shandong Province, China. By calculating the drainage consolidation time, the consolidation factor of 0.015656 m2/d, and the time factor for sediment consolidation of 0.575 were determined. The sediment consolidation time for this test was 9.18 days. The calculation of sediment deposition rate and consolidation time is of great practical significance to guide the Yellow River sediment filling, realize continuous filling, and save reclamation time and cost.