Is the high-speed railway foundation slope constructed from top to bottom or bottom to top?

Whether it is a railway or a highway, whether it is high-speed or ordinary, the specifications stipulate that the construction of roadbed slope protection projects should follow the following sequence:

1. Excavating (cutting) slopes , the overall construction sequence is from top to bottom, with one level of roadbed excavation and one level of protection. When excavating the next level, care should be taken to avoid disturbing the upper level slope protection project.

2. Filling (embankment) slopes, the overall construction sequence is from bottom to top. The roadbed is filled with first-level protection. When filling the upper level, care should be taken to avoid damaging the lower level slope. Disturbance of protective engineering.

The advantage of adopting this construction sequence is to reduce the exposure time of the roadbed slope and prevent the slope from collapsing due to long-term exposure or excessive height. Secondly, it facilitates construction, saves construction costs, and effectively avoids long-distance material transfer in the height direction. The disadvantage is that there are overlapping operations between roadbed excavation and filling construction and slope protection construction, which increases the intensity of production safety management and coordination management.