Document Type

Conference Paper

Publication Date


Publication Details

Weibing Wu, Jialin Xu, Jinfeng Ju and Qingdong Qu, Strong Weighting Events in Shallow Multi-seam Longwall Mining, Proceedings of the 18th Coal Operators' Conference, Mining Engineering, University of Wollongong, 7-9 February 2018, 112-118.


When longwalls are operated underneath previously mined-out workings in shallow coal seams in the Shendong Coalfield, China, extremely strong weighting events often occur and sometimes result in the longwall supports becoming ironbound. The occurrence of such events was analysed through characterising the movement of the rock structures formed by the excavation of the upper seam as well as the associated load transfer mechanism. Three typical mining conditions that have caused frequent strong weighting events were identified: (1) when the longwall face is mining underneath the uphill section of a valley terrain; (2) when the longwall face is advancing out of upper coal pillars; and (3) when the longwall face is mining underneath upper chamber coal pillars. The mechanisms caused strong weighting events under each condition and corresponding prevention and management strategies are discussed.