Study on strata pressure features and support strength site measurement of fully-mechanized top coal caving mining face with shallow mining depth

In order to understand the mine strata pressure features of the fully-mechanized top coal caving mining face with a shallow mining depth and overburden so ft strata and to determine the support strength,based on No. 1603 fully-mechanized top coal caving mining face in No. 16 seam of Lutian Mine as an example,the paper stu died the roof falling down step distance and the powered support load features of the fully-mechanized top coal caving mining face with a shallow mining depth under the 0 verburden soft rock strata. The study results showed that under the shallow depth condition,the roof still had an initial roof weighting and pereiodical roof weight phenomen on.During the roof weighting period,the load increased coefficient was 1. 01 ~ 2.07,the average coefficient was 1. 20 and the load increased coefficient would be reduced . with the mining depth increased. Under the shallow depth condition,the support strength of the powered support in No. 1603 fully-mechanized top coal caving mining face was 442 ~ 802 k N 1 m2,the average value of the powered support would be increased with the mining depth increased and the working resistance of the powered support circulation end would be increased in linear with initial setting force increased. According to the study results,the mining depth obtained was 60 ~ 100 m. A calculation form ula of the support strength for the powered supports in the fully-mechanized top coal caving mining face in a shallow mining depth with the overburden soft rock could quic kly obtain the support strength of the powered support in the fully-mechanized coal mining face under the similar condition and the data were reliable and practical.