Influences of twin-tunnel excavation on settlement of shallow foundation buildings

Based on the centrifugal model tests and numerical calculations, the settlement laws of the upper shallow foundation buildings and ground caused by twin tunnel excavation are studied. The results show that the settlements of different monitoring points in the shallow foundation buildings increase with the increase of soil loss rate. As the soil loss rate increases, the uneven settlements of the upper shallow foundation buildings increase, the vertical displacements of the soil above the tunnel gradually increase, and the range of the settlement trough gradually increases. Under the tunnel spacing of 1D in this project, changes in the excavation sequence of the two tunnels have a relatively small impact on the settlements of the upper buildings and the maximum ground settlement. However, the ground settlements at the tunnel vault excavated first is greater than those at the tunnel vault excavated later.