Abstract Songgang Station of Shenzhen Metro Line 12 Phase II Project and the existing wind pavilion section of Line 6 were taken as the research background. The parameters of the advanced support of horizontal jet grouting pile under the condition of marine strata were analyzed by three-dimensional finite difference software FLAC3D. Based on the analysis and comparison of the surface settlement and displacement results of tunnel excavation under this stratum condition, it was concluded that the stability of surrounding rock during tunnel excavation of marine silt layer was affected by horizontal jet grouting piles with different lengths, section sizes and insertion angles. The results showed that compared with the reinforcement without horizontal jet grouting pile, the surface settlement with horizontal jet grouting pile was reduced by 64.8%. With the increase of the section size of horizontal jet grouting pile, the surface settlement decreased gradually. With the increase of the length and insert angle of horizontal jet grouting pile, the surface settlement increased gradually. In order to find the optimal construction method of horizontal jet grouting pile, the settlement changes of 125 kinds of horizontal jet grouting pile under different supporting conditions were compared and studied, and the economic cost and construction safety were considered comprehensively. It was concluded that the length of horizontal jet grouting pile was 10 m, the pile diameter was 600 mm, and the intercalation angle was 1°, which had the best control effect on the surface settlement deformation of marine silt texture layer. At the same time, Pearson correlation analysis was conducted on the influence of pile length, pile diameter and extrapolation angle of horizontal jet grouting pile on the surface settlement by using IBM SPSS software, and the conclusion was drawn that the influence of pile diameter on surface settlement was greater than that of pile length and greater than that of extrapolation angle.
GAO Bo,LONG Jianping,WU Kai, et al. Analysis of strata deformation law of pre-support of horizontal jet grouting pile for shallow-depth-excavation tunnel in marine stratum[J]. Hazard Control in Tunnelling and Underground Engineering,
2023, 5(1): 64-73.
