Abstract: In order to maintain the stability of double gob-side entries of the 3405 fully-mechanized caving face at a coal mine，the reasonable coal pillar width of the double gob-side entries should be first determined．Based on the geological conditions，the FLAC3D was used to simulate the distribution law of stress，displacement and plastic zone in surrounding rock of the gob-side entries for coal pillar widths of 2，4，6，8，12，20 m．The results show that as the width of gob-side pillar increases the vertical convergence of the entries first decreases，then rises and last decreases again，while the horizontal convergence initially rises and then decreases；when the width of pillar between two entries increases the surrounding rock displacement of the entries decreases on the whole；the peak stress and plastic zone of coal pillars first increase and then decrease with the rise of the pillar widths．After the comprehensive analysis of the simulation results both in technology，economy and effect，we know that the 4m wide coal pillars of both along gob side and between entries are reasonable for the double gob-side entries because the coal pillars are in low stress region and more coal can be mined．According to the findings，the double gob-side entries were excavated and supported with dynamic superposition technology，which successfully solved the supporting problem of the double gob-side entries．

Key words: double gob-side entries, numerical simulation, fully-mechanized caving mining
double gob-side entries, numerical simulation, fully-mechanized caving mining