A new approach to increase land reclamation rate in coal mining
subsidence area: A case study of Guqiao Coal Mine, China
Abstract
Underground coal mining will inevitably cause land ponding in high
groundwater table, which will affect the land sustainable development.
However, the traditional reclamation (TR) is poor in land rate. Thus,
finding a suitable reclamation approach is crucial to alleviate the
conflicts between coal exploitation and land protection. In this paper,
taking Guqiao Coal Mine of China was seriously affected by
mining-induced ponding as an example. Firstly, dynamic distribution of
surface subsidence and land damage from 2007 to 2017 was revealed base
on concurrent mining and reclamation (CMR). Second, the land-water
layout of five reclamation schemes (no reclamation, TR, CMR I, CMR II
and CMR III) were simulated. Then, and the dynamic filling elevation
model and filling thickness model were constructed. Finally, the
sequence of earthwork allocation was optimized. The results revealed
that: 1) reclaimed land area: CMR III > CMR II
> CMR I > TR > no reclamation; 2)
The digging depth is directly proportional to earthwork volume and land
area, and inversely proportional to water area, but with increase of
digging depth, the increase in the reclaimed land area relatively slowed
down; 3) CMRs had reclaimed 426.31~637.82 ha and
259.62~471.13 ha more than the no reclamation and TR
respectively. Compared with the no reclamation and TR, CMRs can increase
the proportion of reclaimed land by 33.77~50.52% and
20.57~37.32% respectively. The research results provide
a reference to increase the reclamation rate of mining areas in the high
phreatic table.