Sentence examples for key stratum from inspiring English sources

If the position of the primary key stratum can be moved upward to exceed 10 times the mining height the possibility of support crushing and water inrush disaster caused by key stratum compound breakage will be lowered.

The concept of water-resistant key strata further enriches the content of the key stratum theory and provides a theoretical basis for water-preservation mining.

Formulas for calculating the stress and deformation of the key stratum in the surface underground combined mining were derived and the mechanical characteristics of the key strata were revealed.

The results show that when an overburden structure that may cause support crushing and a water inrush accident exists the weakening of the primary key stratum, which thereby reduces its weighting step, roof pre-blasting is both feasible and effective.

If the primary key stratum is not relatively strong and hard, the panel width can be designed based on a lower key stratum (e.g., KS2 in Fig. 7).

According to the control action of key strata on surface subsidence (Xu et al. 2005), panel width can be designed by stabilizing the most upper key stratum (primary key stratum, KS3) during the extraction (Fig. 7).

The principle of water-resisting key strata (WKS) is proposed to establish a model capable of guiding and developing water-preserved mining technology.

In this study, we established a main roof strata model with loads in accordance with the theory of key strata to investigate the stability of the overburden in solid dense filling mining.

Practical engineering applications indicate that this discrimination method and its corresponding computer program on water-resistant key strata are accurate and reliable and can satisfy the actual design needs of water-preservation mining and thus have instructional importance for water-preservation mining in mining areas lacking water.

NotesS is limited span of key strata and θ is the break angle of overburden strata.

The limit span of the key strata can be calculated based on the beam model.