Prediction method for subgrade settlement in construction period of subway tunnel by drilling and blasting method

The invention discloses a prediction method for subgrade settlement in a construction period of a subway tunnel by a drilling and blasting method, The prediction method comprises the following steps:1, acquiring physical and mechanical parameters of a tunnel pre-passing rock-soil body, and respectively calculating a settling tank width coefficient K1 and a settling tank width coefficient K2 by adopting a formula (1) and a formula (2); 2, adopting a formula (3) to budget the width i of the roadbed settling tank after drilling and blasting, wherein the formula (3) is shown as follows: i = K1z1+ K2z2; and 3, calculating a radial uniform convergence parameter epsilon according to the physical and mechanical parameters, calculating a subgrade settlement maximum value Smax and a subgrade settlement value Sx according to the stratum loss rate V1 and the predicted subgrade settlement groove width i and stratum loss rate V1 of the tunnel to be excavated. The invention provides a settlement prediction method suitable f