METHOD OF MONITORING VERTICAL DISPLACEMENTS AND DEFORMATIONS DURING CONSTRUCTION OF METRO TUNNELS Russian patent published in 2024 - IPC E21C39/00 

FIELD: construction.

SUBSTANCE: invention relates to construction of tunnels and underground station workings of metro, collectors in conditions of dense urban development and can be used to control the safety of undermining of buildings on the surface, which have fallen into the zone of influence of the construction of underground structures of the subway, as well as to select measures for their protection. Method of monitoring vertical displacements and deformations during construction of metro tunnels involves laying reference points into the roof along the axis of the tunnel, observing vertical displacements of reference points, determining their subsidence, inclinations and curvature. Four reference points are laid as the tunnel is being drilled, the location of the first reference point is determined by the angle of influence of the tunnel working on the earth's surface in the main section of the shift trough, which is drawn from the building outline to the intersection with the roof of the design position of the tunnel, the rest of the reference points are laid as the tunnel is being driven through a certain interval. Systematic levelling begins immediately after the first reference point is laid, and then continues as the remaining reference points are laid. Earth surface subsidence is determined at points, which are obtained by intersection with surface of corners of influence of tunnel working on earth surface in main section of shift trough, which is drawn from the laid reference points in the tunnel, the subsidence values of these points are determined from the condition that the ratio of the subsidence of any underground reference point to the subsidence of the corresponding point on the earth's surface is equal to the coefficient of compliance with mining and geological conditions of tunnel construction, multiplied by the square root of the ratio of the vertical distance from the underground reference point to the earth's surface to the vertical distance from the underground reference point to the upper boundary of the delamination zone of the tunnel roof. Obtained from monitoring subsidence at points on the surface is used to determine inclination and curvature as the first and second derivatives of subsidence. Monitoring observations are completed when, in two next series of observations, subsidence of the first point on the earth's surface is obtained, which differ from each other by no more than 5 %, this means that this point fixes all stages of development of displacements and deformations of the shift trough moving after the movement of the bottom of the tunnel, including the stage of the beginning of the flat bottom formation.

EFFECT: providing control over development of vertical displacements and deformations on a densely built-up surface along the line coinciding with the axis of the tunnel under construction, assessment of safe impact obtained from monitoring deformations on buildings, structures located in this zone, and selection of measures for their protection.

1 cl, 1 ex, 5 tbl, 1 dwg