Buckling and Post-Buckling Behavior for Roof Strata in Longwall Mining
In accordance with the occurrence behavior of roof strata and the fracture characteristics of key stratum in shallow seam longwall mining, this paper studied the post-buckling behaviors of key roof stratum in the process of mining by using initial post-buckling theory, which derived a critical load and a breaking span of the main roof during the first weighting, determined the final subsidence for broken key stratum, and presented an application with the example of Daliuta 1203 face. The results indicate that the rock blocks a in are state of non-equilibrium after main roof breaking, the equilibrium path of main roof is unstable from breaking to final subsidence; thick unconsolidated layers above roof have effect on post-buckling behaviors of key stratum; the stability for bifurcation point equilibrium configuration and post-buckling equilibrium path of roof strata could be revealed and an effective method for determining displacement field of imperfection structure could be provided by using initial post -buckling theory.
Mingjin Chu, Xiangran Li, Jingzhou Lu, Xingmin Hou and Xiaogang Wang
Q. Song and Z. L. Yang, "Buckling and Post-Buckling Behavior for Roof Strata in Longwall Mining", Applied Mechanics and Materials, Vols. 170-173, pp. 751-754, 2012