Abstract: Through pre-supporting member stress testing, roof dynamic pressure of the rock after stability is obtained. Then the wall of concrete block compressive strength is tested is drew, When the test block reached roof rock stress value, wall stress can play a supporting effect, concrete block with curing time is the removed time of pre support monomer column. Combining midas software with the physical parameters of the concrete block and separating wall design size, numerical simulation is used to check whether the wall can withstand the roof load or not after the demolition of the monomer column. The results are that the wall in the roof can withstand loads after 20 days and determine the time of removal of monomer column.