Excavation: When the subgrade surface is lower than the original ground, part of earthwork is excavated from the original ground to the subgrade surface.
Mining function:
1. Earthwork excavation to meet the needs of building foundation (removing miscellaneous drawings, preventing foundation from freezing and improving foundation bearing capacity).
2, the need for site leveling.
3, the need of engineering pipeline laying.
4, rain (sewage) water discharge needs.
Extended data:
Fill should be filled with similar soil as far as possible. If two kinds of fillers with different permeability are used in the filler, they should be filled in layers, with the filler with less permeability in the upper layer and the filler with greater permeability in the lower layer. Various soil materials shall not be mixed, so as not to form water pockets in the fill.
The filling construction shall be carried out in nearly horizontal layers and compacted by layers. The thickness of each layer depends on the soil type and the compaction machine selected. The compaction quality of fill should be checked by layers, and the upper layer can be filled only after it meets the design requirements. When the fill is located on the inclined ground, the slope should be dug into steps first, and then filled in layers to prevent the fill from moving laterally.
Baidu Encyclopedia-Filling