Site flooding
No Chinese content provided for translation.Due to the construction period being in spring, when the region experiences dry and scarce rainfall, no drainage ditches were set up in the early stages of the project, leading to extensive flooding during rainfall. To address this situation, the following measures have been adopted: ① All water-soaked soil must be completely removed and cleaned before proceeding to the next phase; ② The fill area will maintain a certain cross slope with the center slightly elevated and the ends slightly lower to facilitate drainage; Open drainage ditches will be excavated around the fill area, connected to sedimentation ponds, and water will be pumped out from the ponds. A sedimentation pond will be installed at each corner of the fill area or every 20-40 meters.
2. Excavation backfill settlement
The backfill soil in the foundation pit has shown some settlement. If foundation settlement occurs after the construction of the road structure layer, it could lead to cracking of the road structure layer and overall damage. Prevention and control measures: ①Before backfilling, the silt, branches, garbage soil, and other debris at the bottom of the pit in the backfill area should be cleaned up and the accumulated water drained; ②The backfill soil should be filled and compacted in strict layers, with the thickness of each layer of loose soil not exceeding 300mm. The backfill soil material and moisture content should meet the specifications, and the dry soil quality density should be tested and meet the standard requirements; ③The backfill soil should not contain soil blocks with a diameter greater than 50mm, and there should not be too many dry soil blocks; ④If the settlement continues to develop, it is necessary to excavate the backfill soil and refill it with impermeable clay or silty clay, or use 2:8 or 3:7 lime soil, compacting it again.
3. Soil compaction reveals springs in the fill area
During the compaction of the soil fill for the strong foundation, the area of stress sinks while the surrounding area rises, forming a plastic condition, with a sensation of stepping on a spring. This is due to the excessive moisture content of the soil, which exceeds the required moisture content for the specified compaction degree. Solutions: ① Remove organic soil and silt, control the moisture content of the backfill, and re-fill the soil after it has been turned and dried in the sun; ② Install proper drainage systems around the fill to prevent surface water and construction water from entering the fill area; ③ Mix absorbent lime powder, gravel, and other materials with the rubber soil to absorb moisture from the soil, thereby reducing the soil's moisture content. In case of urgent construction, remove the rubber soil entirely and replace it with a 2:8 or 3:7 lime soil mixture, compacting it densely.
