This paper aims to evaluate the severities and causes of ground surface building and cropland damages after coal mining in a better way, and to clarify the correlation between the damage assessment indexes that influence mining. Against the backdrop of multi-seam mining in certain coal mines in China, the estimated results of each displacement and deformation were analyzed using GIS technology. The damage range determined for each deformation index is divided according to the displacement and deformation combined with the virtue of damage judgment threshold. The damage ranges on the ground surface based on the comprehensive value of each displacement and deformation index were obtained through superimposing those ranges delineated by each displacement and deformation index, and the law on influence from displacement indexes upon various levels of damage was analyzed in a quantitative manner accordingly. The results showed that coal mining destroyed 14 buildings and a cropland area of 11.96 hm²; among them, building damage was only associated with displacement indexes E (horizontal deformation) and T (inclined deformation). Seven buildings were solely destroyed by T alone; five buildings were solely damaged by E; two buildings were damaged jointly by E and T; and, moreover, with the aggravation in building damage level, the proportion of building damage due to E decreased while the proportion of building damage under the same level due to T increased. Regarding cropland destruction, the damage due to T accounted for 33.48% while the damage jointly caused by W (Subsidence), E and T accounted for 30.45%. Moreover, the proportion of damaged cropland area due to inclined deformation T was positively correlated with cropland damage level. These findings can provide a reference for rational judgment regarding civilian building and cropland destruction on the ground surface after coal mining.

To reveal the overburden failure characteristics during backfill mining, theoretical analysis based on the theory of plates and shells and field measurements were combined. Based on the theory of plates and shells, a mechanical model for the overburden failure mechanism during backfill mining was established, through which the fracture conditions of overburden during backfill mining were judged. By analyzing the fracture process and revealing the fracture mechanism, the fractured zone in overburden during backfill mining was found not to develop uniformly, but changed in a leaping manner. Field measurement was conducted taking the 1327 working face in Xima Coal Mine (Shenyang City, Liaoning Province, China) as an example to monitor and analyze the roof-to-floor convergence (RFC), strata behaviors at the working face, and overburden failure during backfill mining. Monitoring results show that the distance between the monitoring points and the working face was highly consistent with the periodic weighting interval when the RFC increased in a leaping manner; the RFC grew in a leaping manner after each roof weighting, as well as the fractured zone. By monitoring and analyzing overburden failure, it was determined that the maximum height of the fractured zone was 10.7 m and a leaping phenomenon was present in the development process of the fractured zone. The conclusions of theoretical analysis were completely consistent with those of the field measurements, thus confirming the leaping development of the fractured zone in overburden during backfill mining.