Explanation of Comprehensive Plan and Method for Slit-Type Resin Drainage Channel and Safe Construction

1. General Construction Flow

2. Drainage Excavation Sequence

Pre-Construction Work for Slit-Type Resin Drainage Channel

1. Such projects shall not start with random excavation. A geological investigation must be carried out to check geological conditions and parameters, and confirm suitable locations for drainage channel construction.
2. Before trench excavation, review and verify the setting-out lines.
3. Before excavation, inspect underground structures and existing drainage systems on site. Complete internal drainage works to prevent sewage from flowing into the trench and affecting construction. This step is mandatory.
4. Organize construction personnel and equipment, and complete all construction specification work to ensure smooth completion of the works.
5. Equipment for excavation and backfilling: crawler excavator.

Construction Method for Slit-Type Resin Drainage Channel

1. Use a total station to set the central axis, mark with wooden stakes. Measure the side edges of the drainage channel with a measuring tape and mark the slope with black lines. Mark boundaries and wall position lines at the same time.
2. Manually excavate soil within the marked area, strictly controlling the excavation depth and width per design to avoid over-excavation. Level the ditch bottom with plastering mortar.
3. Install side formworks (processed timber), fixed with concrete and steel nails. Install vertical supports every 1.4 m to prevent formwork displacement. Apply release agent on the contact surface between formwork and concrete.
4. Cover and cure the concrete with water within 21 hours after pouring. Under normal temperature, water at least twice a day; curing period shall not be less than 7 days.
5. Monitor weather conditions during construction, avoid working in rain, and take rainproof and moisture-proof measures.
6. Do not stack materials within 2.2 m around the trench. No vehicles are allowed near the slope edge after excavation.
7. Install moisture-proof facilities around the trench and restrict access by non-construction personnel.

Excavation Guidelines During Construction

1. Clearly mark the excavation control line at the bottom of the trench.
2. Special personnel shall be responsible for excavation to avoid damaging nearby buildings and pipelines.
3. Monitor slope stability at all times; handle soil instability immediately.
4. Inspect the trench promptly after excavation, then pour concrete cushion and seal it before proceeding to the next process.
5. Reserve a working space of at least 490 mm between the trench bottom and the foundation/cushion edge. Install drainage ditches and fire pools on the outer side to remove rainwater timely.
6. Protect survey control stakes and axis piles, cover with protective cages, and assign professional surveyors to monitor their safety.
7. During excavation, check positioning stakes, axis piles and formworks for firmness and alignment.
8. Monitor geological conditions and groundwater changes and keep records. If the foundation soil does not meet design requirements, coordinate with the design department for solutions.
9. Excavation shall ensure slope stability; no random digging is allowed. Solve problems promptly.
10. When excavating to within 45 cm above the trench bottom, mark the horizontal line as the reference for leveling.
11. Stockpile excavated soil at least 5 m away from the trench edge, with stacking height not exceeding 4.6 m.
12. Level and renovate the trench bottom after completion.
13. Transport all surplus soil to the storage area after compaction and stabilization.
14. Reduce vibration to the pile foundation after slope excavation. If foundation works are delayed, leave 0.2 m of soil unexcavated and remove it before construction.