Analysis of Influence of Key Strata on Caving Height in Single Full-seam Mining

This paper researched caving zone height of overlying strata by theoretical analysis and analog simulation and obtained that with mining face advancing,whether the key strata reached caving zone was dependent on fracturing fragmentation,thickness and length.Key strata as research object,this paper set up a mechanical model of four-side clamped elastic thin slab to deduce its limit fracturing pace principle and judge whether it reach caving zone after fracturing.Based on an engineering case,actual fracturing pace was calculated which was close to observation value.Thus,a confirmation method for caving zone height of overlying strata controlled by key strata in full-seam mining formed.