Bolt-grouting technology is an effective way to maintain the stability of soft rock roadway

and its effects rely heavily on the grouting time. The mechanical characteristics of ruptured soft rock reinforced by grouting are analyzed

and the rational grouting time for soft rock roadway is optimized by numerical simulation using the strain softening constitutive law in FLAC2D. The results show that as the grouting time lags

the infiltration scope of the grout in rock increases gradually but the strength of rock reinforced by grouting decreases dramatically

and the deformation of roadway decreases first and then increases. On the basis of this

a method integrating numerical simulation and monitoring for determining the rational bolt-grouting time is proposed and better results have been achieved in engineering practice. This method provides a favorable guidance for the construction and design of bolt-grouting support in soft rock roadway.