The mechanism of the geological deformation caused by shield tunneling construction was combined with a threedimensional numerical simulation method to simulate the displacement of bridge piles during the smallangle side crossing of highspeed railway bridge group piles in subway shield tunnels constructed in sandy areas. Analyses were conducted on the mechanism of the impact of metro shield tunnels on highspeed railway bridges when the shield reaches the front of the piles, reaches the piles, and moves past the piles, as well as when the shield tail is detached and after the shield passes the piles. Three protection plans were then proposed for highspeed railway bridges, which included isolation pile measures, geological reinforcement measures, and isolation piles + geological reinforcement. Threedimensional numerical simulations were used to analyze the entire process of shield tunnel boring through the pile groups of highspeed railway bridges under the conditions of no protection scheme and when adopting the above three protection schemes. The findings revealed that without protective measures or with the sole use of ground reinforcement or isolation piles, the deformation of a highspeed railway bridge exceeds the allowable standards during the lateral passage of a shield tunnel. However, with the implementation of both isolation piles and ground reinforcement, the deformation remains within the prescribed limits. After the scheme comparison, the design scheme of isolation piles and ground reinforcement were ultimately adopted for implementation. During the onsite implementation, the entire process was monitored, and the monitoring results were consistent with the numerical calculations, verifying the rationality of the highspeed railway bridge protection plan.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |