Coal bursts present one of the most severe hazards challenging the safe operations in underground coal work environments. In Australia, these events are becoming increasingly frequent as coal measures are mined progressively deeper. This study is supported by the Australian Coal Association Research Program (ACARP) which aims to better understand the phenomena of coal burst. In this paper the dynamic fracture process of coal bursts was successfully simulated in the coal roadway. This was achieved using dynamic analysis utilising DRFM2D routine by Venticinque and Nemcik (2017) in FLAC2D (Itasca, 2015) which complemented previous study observations by Venticinque and Nemcik (2018). This is significant because until now the evolving dynamic rock fracture process during coal burst remained unknown. Additionally, coal/rock burst events were shown from simulation as being largely driven by the propagation of shear fractures from within the rib. This was demonstrated to produce effect forcing the dynamic conversion and release of potential energy stored as compressive strain in the rib into kinetic movement of the entire rib section. This entire process was shown to occur very fast taking approximately 0.2 seconds for a coal burst to fully establish, with ejection of several meters of rib at a velocity of 1.6 m/s produced in the model of an underground coal roadway having 550 m depth of cover.