Abstract: In view of the mining conditions of large inclined and “three-soft” thick seam in No.72 Coal Seam of Liudong Coal Mine, the stability and suitability of combination hydraulic support in the high inclined and “three-soft” thick coal seam were studied by using theoretical analysis and field measurement. The results show that the combination support stability is affected by the supporting quality factors including column setting load, uneven coefficient of setting load and prop-setting angle, etc, and the geological factors including dip angle of coal seam, and roof and floor characteristics, etc. The support stability is enhanced with the increase of column setting load, but reduced as the seam inclination increases. Thus, appropriate increasing of setting load in the under side column of combination support will help to improve the support stability, while the reasonable prop-setting angle is one of the important guarantees to improve the support stability in the large inclined seam conditions. In the seam conditions of Liudong Coal Mine, prop-setting angle should be around 6°, and the largest adaptation dip angle of the support is 36.48° Measures have been carried out to ensure the stability of support system in field applications, such as improving the sealing performance of hydraulic system to prevent leakage, enhancing column setting load, and maintaining good-bit states of support and columns.

Key words: large inclined and “three-soft&rdquo, thick seam；hydraulic powered support；stability analysis