Abstract: In this study, a scheme of jacking framed bridge with loading was proposed based on the concept of unload-load balance. Taking a highway under Beijing-Shanghai high-speed railway as an example, the deformation and control technology of its piers were also studied. The results show that the highway is excavated at a depth of 10 m under the high-speed railway bridge, and the excavation volume is nearly 100, 000 square meters. The uplift deformation of the high-speed railway is effectively controlled by adopting the scheme of the jacking framed bridge with loading, in which the monitoring and loading measures of the soil heap on the top of the framed bridge, under the bridge and in the framed bridge are carried out. After three months of operation, the cumulative maximum differential settlement of adjacent piers is 2.7 mm, which meet specifications with a margin of 46%. Rail inspections reveal that the regularity of ballastless track satisfies operational requirements. Through comparative analysis, the compressive modulus of silty clay in the numerical model can be determined under the stress state of experimental P0 - P0 + 100 kPa (P0 is the soil self-weight stress), and the unloading modulus can be 3?5 times of the compressive modulus.

Key words: jacking framed bridge with loading, under high-speed railway, monitoring, deformation control