The invention discloses a non-
coal stratum tunnel harmful gas
risk evaluation method and
system and a medium, and relates to the technical field of
tunnel construction, and the method comprises the steps: building a Poisson's
ratio sequence of an unexcavated section rock
mass along the longitudinal direction of a tunnel; a plurality of advance
drill holes are constructed in the initial tunnel face and measured while drilling, and a harmful
gas concentration sequence of all the advance
drill holes is established; building a harmful gas emission quantity sequence of the rock
mass section of the unexcavated section along the longitudinal direction of the tunnel; fusing the Poisson's
ratio sequence, the harmful
gas concentration sequence and the harmful gas emission quantity sequence to generate a harmful gas
data matrix; construction excavation is conducted, multiple harmful gas emission amount data are obtained and substituted into the harmful gas
data matrix, harmful gas emission amount data of the rock
mass sections of the rest non-excavated sections are obtained through calculation, and the danger level of harmful gas is judged. According to the method, the limitation of a traditional single detection means is overcome, the overall
distribution rule of the harmful gas of the unexcavated section can be reflected more accurately, and the accuracy of
risk evaluation of the harmful gas is improved.