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An approach coupling the particle element and the block element is presented and a constitutive model of hydraulic support introduced into the continuum-discontinuum element method to simulate the top-coal drawing process, while the Bergmark-Roos model for single-support coal drawing of single support is extended to multiple supports. Taking panel 8202 of the Tongxin coal mine in China as an engineering example, with an average thickness of 15 m and a depth of 377-517 m, it is shown that under the interaction between hydraulic support and surrounding rocks the final drawing body of the initial draw appears as an irregular ellipsoid. During different support-moving cycles the coal-rock structure affects the amount of coal drawn and the support resistance. A statistical comparison of the amount drawn from 100 openings indicates that the standard deviation of the amount in automated one-round caving is 1.83 m2 less than the 8.23 m2 in traditional caving and the amount drawn is more uniform. For multi-round caving techniques the average recovery rate remains at 79.4% and the rate of rock mixing less than 1%. Comparison of coal caving techniques indicates that automated four-round caving is the optimum technology, with the largest rate of change in standard deviation of amount drawn as well as the largest top-coal recovery rate., An approach coupling the particle element and the block element is presented and a constitutive model of hydraulic support introduced into the continuum-discontinuum element method to simulate the top-coal drawing process, while the Bergmark-Roos model for single-support coal drawing of single support is extended to multiple supports. Taking panel 8202 of the Tongxin coal mine in China as an engineering example, with an average thickness of 15 m and a depth of 377-517 m, it is shown that under the interaction between hydraulic support and surrounding rocks the final drawing body of the initial draw appears as an irregular ellipsoid. During different support-moving cycles the coal-rock structure affects the amount of coal drawn and the support resistance. A statistical comparison of the amount drawn from 100 openings indicates that the standard deviation of the amount in automated one-round caving is 1.83 m2 less than the 8.23 m2 in traditional caving and the amount drawn is more uniform. For multi-round caving techniques the average recovery rate remains at 79.4% and the rate of rock mixing less than 1%. Comparison of coal caving techniques indicates that automated four-round caving is the optimum technology, with the largest rate of change in standard deviation of amount drawn as well as the largest top-coal recovery rate.