Explanation of Resin Linear Drainage Channel and Comprehensive Construction Planning Process

一、Construction Flow (General)

二、Pipe Jacking at Drainage Outlet (Step-by-Step)

Pre-Construction Preparation for Resin Linear Drainage Channel

1. This project cannot start with random excavation. An engineering investigation must be conducted first, including reviewing survey data and indicators to confirm suitable locations for drainage channel construction.
2. Before determining foundation pit and pipe jacking construction, check and verify the setting-out lines.
3. Before excavation, inspect underground structures and existing drainage systems on site. Complete external drainage works to prevent groundwater from flowing into the foundation pit, which would affect construction.
4. Organize construction personnel and machinery, and conduct all necessary technical disclosures to ensure smooth construction.
5. Machinery for earth excavation and backfilling: fixed and crawler mini-excavators.

Construction Process of Resin Linear Drainage Channel

1. Use a theodolite to set the central axis line, mark with wooden stakes. Measure the trench edges with a square ruler and mark the slope with black lines. Mark the boundary and wall positions.
2. Manually excavate soil within the setting-out area, strictly controlling the depth and length per design to avoid over-excavation. Level the pit bottom with concrete.
3. Install side formworks (made of loose timber), fixed by mortar and steel pins. Install vertical supports every 1.1 m to prevent formwork displacement. Apply the release agent on the contact surface between the formwork and the concrete.
4. Within 12 hours after concrete pouring, cover and cure the concrete by watering. Under normal temperature, water at least twice a day; the curing period shall not be less than 7 days.
5. Monitor weather conditions during construction, avoid working in rain, and take rainproof measures.
6. No materials shall be stacked within 2.2 m around the foundation pit. No vehicles are allowed near the excavated pit edge.
7. Install rainproof facilities around the foundation pit and restrict access by non-construction personnel.

Safety Measures for Earthwork & Backfilling

1. Mark the control lines for pipe jacking on both walls of the foundation pit.
2. Manual backfilling is prohibited from impacting surrounding buildings and pipelines.
3. Monitor slope stability at all times; handle landslides immediately.
4. Conduct timely inspection after excavation, then pour concrete cushion and seal it before proceeding to the next process.
5. Reserve a working space of not less than 500 mm between the foundation pit bottom and the frame/cushion edge. Install trenches and catch wells on one side to drain rainwater timely.
6. Protect survey control stakes and axis piles, install steel cages and assign surveyors to guard them.
7. During pipe jacking, check whether positioning stakes, axis piles and formworks are firm and correctly aligned.
8. Monitor soil condition and groundwater changes, keep records. If the foundation soil does not meet design requirements, coordinate with the design department for solutions.
9. Backfilling shall ensure subgrade stability; prohibit random drilling. Handle problems promptly.
10. When excavating to 45 cm above the pit bottom, mark the axis line as the leveling reference.
11. Stockpile excavated soil at least 5.1 m away from the trench edge, with stacking height not exceeding 4.7 m.
12. Level and inspect the pit bottom after excavation.
13. Remove and transport all surplus soil after excavation and stabilization.
14. Reduce vibration to the foundation after pit excavation. If frame construction is delayed, leave 0.5 m of soil unexcavated and remove it before construction.