ABSTRACT
As the excess pore water pressure in the foundation gradually dissipated after the completion of the tunnel, the drainage and consolidation of the foundation caused the tunnel to settle. Through the PLAXIS 2D finite element software, a two-dimensional numerical model of the open-cut tunnel in the soft clay area is established. The influences of the elastic modulus and depth of the reinforced soil under the grouting reinforcement method, the number of pile foundations under the cement mixing pile reinforcement method, and the length of the pile foundation on the post-construction settlement of the tunnel are studied. The analysis results show that with the increase of the elastic modulus of the reinforced soil and the depth of reinforcement, the settlement of the tunnel decreases, but the increase of the elastic modulus of the soil will weaken the control effect. It is recommended that the reinforcement plan is considered comprehensively according to the construction difficulty and budget in the project; as the number and length of pile foundations increase, the settlement of the tunnel decreases. When the number of cement mixing piles exceeds two, the impact on the settlement of the tunnel will decrease.
