## 1 Introduction  
The newly built Shanghai-Nanjing Intercity Railway and some sections of the existing Beijing-Shanghai line are adjacent to each other, with a parallel length of about 170 km and a distance of 4-15 m. The roadbed project adopted a new type of composite foundation with piles and rafts and construction processes, such as foundation excavation, pile formation, and filling. This will bring security risks to the adjacent existing railways. The disturbance of structures surrounding new projects has increasingly attracted the attention of engineers and technicians, and it is now common to study the construction impacts of tunnels, foundation pits, and blasting [1; 2]. [PERSON] [3] used the superposition principle, the finite-element load-structure method, and the forced-displacement method. He calculated and analyzed the stability and deformation of the station structure adjacent to the foundation pit excavation. This study provided the control standard of station structure deformation for foundation pit construction. [PERSON] [4; 5; 6] elaborated the research status of the construction problems adjacent to the soft soil foundation pit from four aspects: theoretical research, model testing, numerical simulation, and field analysis, and sorted and analyzed the measured data of different projects. It was found that there is a certain linkage between the deep displacement of the soil around the foundation pit, the deformation of the retaining structure, and the deformation of the adjacent subway tunnel. [PERSON] [7] used theoretical formula derivation, which is based on solving the curvilinear equation of a quartic polynomial, considering the pile length, hole-wall shape, displacement boundary conditions, and soil material nonlinearity, and applied the variational principle to deduce the pile driving and extruding soil. The displacement, strain, and stress field solutions, and the research results, provide a theoretical basis for the selection and design of protective measures in the construction of pile pressing. [PERSON] [8] researched the dynamic pile-pressing process using a finite-element model and field measurements. He calculated and simulated the vertical displacement field of soil extrusion caused by pile driving and compared the calculations with the actual measurements. The study found that the maximum compacting displacement delays the pile-sinking depth. [PERSON], [PERSON] et al. [9] simulated the excavation process for the foundation pit through an indoor model test and obtained the deformation change and distribution law for the supporting structure. [PERSON] [10] and others developed an artificial intelligence Internet of Things (AIoT)-based system for real-time monitoring of tunnel construction. Foundation pit tunnels currently undergo routine deformation monitoring for supporting structures in accordance with regulations and specifications. With the development of detection technology, the use of radar monitoring methods such as geological advance forecasting to provide early warnings in the construction of underground caverns have received increasing attention in the engineering field [11; 12; 13]. The research results for the deformation control of structures such as tunnel foundation pits were relatively rich, covering the main technical means such as on-site monitoring, theoretical analysis, simulation calculations, and model tests, but less research has been carried out on the problem of subgrade deformation control in operation. [PERSON], [PERSON] et al. [14] proposed a monitoring method for mountain highway slopes that used FEM analysis, a displacement meter, a rain gauge, and other hardware monitoring systems to test the displacement and rainfall. [PERSON] [15] established a remote health monitoring system for mountain reservoirs and shore subgrades based on GPRS data transmission. Through the wireless remote transmission of safety monitoring data, the health status of subgrades was determined, which provided a basis for safe highway operation and subgrade disease prevention.