Compared with that of equal-length working faces, the mechanical evolution mechanism overburden rocks in “knife handle”-type mining sites is more complex. The form roof fracture knife handle-type mines variable, and stress distribution near interface concentrated, thereby severely threatening safety mining. To elucidate characteristics fully mechanized top-coal caving sites, geological conditio...

Gradual instability of coal pillars left behind underground with room mining is one the main reasons for sudden roof caving in gob, surface subsidence, and other significant hazards. Moreover, implies great losses resources. In this paper, failure mode pillar process were analyzed according to coalfield regional engineering geological hydrogeological conditions. A numerical model was adopted st...

The policy of driving organization such as Highways Agency is towards the use of performance related specifications. This policy and adoption of European wide aggregate standards on the one hand, and sustainable construction pressures on the other, all strongly emphasize on further need for more developments to specifications and performance assessment methodologies inst...