Assessment of burned coal shale properties based on cyclic load Marcin Grygierek, Piotr Kalisz, Krzysztof Pacześniowski, Andrzej Pytlik and Magdalena Zięba E3S Web of Conf., 36 (2018) 03001 Published online: 09 April 2018 DOI: 10.1051/e3sconf/20183603001