The influence and calculation method of ground settlement induced by tunnel construction in sand

摘要

In order to study the influence of tunnel construction on ground settlement in sand, the distribution and variation characteristics of ground settlement during tunnel construction were explored through model tests. The results showed that during tunnel construction in sand, the variations of surface settlement and ground settlement at different ground depths were basically the same at the same monitoring section. The distribution and variation characteristics of the ground settlements along the width and length directions of the tunnel were basically the same. The ground loss increased in power function from the surface to the underground. The maximum ground settlement and the width coefficient of the settlement trough were strongly positively correlated with the ground loss. Based on the experimental study and statistical analyses, the relation between ground loss and ground surface loss at different burial depths was established. The calculation of an equation of ground loss at different depths was put forward, and the calculation of an equation of the width coefficient of ground settlement trough was modified, both of which enable the calculation for ground settlement in an arbitrary position above the tunnel during tunneling.