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located in the northwest of China, are characterized by low dips and large thicknesses and are thus suited for full thickness extraction. Since the mid-1990s, the Shendong coalfield has been developed into one of the largest in the world (Ning, Liu, and Tan. 2014; Ning et al., 2017). Recent developments in mining equipment have made it possible extract entire seams up to 5.0 m thick in a single cut. This method, termed the ‘super-great mining height longwall face’ (SGMHLW) method, has been widely adopted in the Shendong coalfield (Table I) (Ju and Xu, 2013; Peng, Li, and Zhou 2015; Zhang, Fan, and Ma 2011). According to some studies, sudden support-closure incidents often occur when using the SGMHLW method. The key to solving this engineering issue is to have a clear understanding of the structural characteristics and movement laws of the overlying strata. For instance, the load on the supports is related to the movement of the roof stratum as a response to the mining activities. To date, extensive studies have been conducted to obtain a clear understanding of the mining-induced cave-in response of the strata (e.g. roof movement and failure responses). These studies have used different methods, such as numerical simulations, theoretical analyses, physical modelling, and on-site investigations (Ghose and Dutta, 1987; Yasitli and Unver 2005; Trueman, Lyman, and Cocker 2009; Shabanimashcool, Jing, and Li 2014; Tan, Li, and Ning 2017; Jiang, Sainoki, and Mitri 2017). Based on field observations, Peng and Chiang (1984) suggested that the first cave-in event involves shear fracture of the main roof before that of the face, while the subsequent and periodic cave-in events involve cantilever instead of Voussoir beam collapse. Song (1988) proposed that the rock blocks in the main roof stratum rotate and interlock with each other to form a jointed Voussoir beam when the stratum deflects downwards. Sofianos (1996) developed a model of Voussoir beams in the hard roof through numerical simulations. These studies indicated that roof cave-in is a dynamic process involving rock fracturing, disintegration, and movement. However, all these studies were conducted with a mining height of less than 6.0 m, i.e. under normal mining height extraction conditions. In recent years, considerable attention has been given to the strata failure and movement pattern induced by the mining of thick coal seams, for example, the longwall top coal caving (LTCC) and SGMHLW methods (Gong and Jin 2008; Yu, Zhao, and Kuang 2015; Yu, Zhao, and Xiao 2017). Owing to the high output and high efficiency of the SGMHLW method compared with the LTCC method at present, it is popular for mining thick coal Structural characteristics of strata overlying of a fully mechanized longwall face: a case study