Preparation before Construction
Site cleaning: Remove debris, weeds, tree roots, etc. within the construction area. Trim the slope surface to make it smooth and flat, and remove loose rocks and dangerous rocks.
Material inspection: Check the quantity and quality of geocell materials to ensure that indicators such as tensile strength, elongation, and puncture strength meet the design requirements. The appearance should be free of damage, holes, etc.
Construction setting-out: Determine the laying range and position of the geocell according to the design drawings and the actual site conditions, and carry out accurate positioning and setting-out.
Foundation Treatment
Base leveling and compaction: Level and compact the base soil to ensure that the base is solid and stable, and the bearing capacity of the foundation meets the design requirements. If the foundation is weak, reinforcement measures such as replacement filling and compaction are required.
Geocell Laying
Unfolding and laying: Unfold the geocell on the slope surface and lay it flat in the predetermined position. Keep the geocell flat and straight, and avoid twisting or wrinkling. The geocell should be laid from top to bottom in the main stress direction, with the geocell sheets perpendicular to the highway subgrade. It must never be laid horizontally.
Fixing and connecting: Fix the geocell using methods such as anchor nails, rivet piles, or ballast to ensure its accurate position and stability. Two adjacent geocells need to overlap by a certain length, generally about 0.2m. Along the transverse direction of the subgrade, use iron wire to connect the overlapping parts of the geocells or use professional fasteners for connection, ensuring that the strength of the connection meets the design requirements.
Filler Filling
Filler selection: Select appropriate fillers, such as sandy soil and gravelly soil. The filler should have good gradation and water permeability. Avoid using soil materials containing excessive impurities, silt, or organic matter.
Layered filling: Adopt the method of layered filling. The thickness of each layer of filler is generally not more than 30cm. Use a loader or bulldozer to evenly spread the filler in the geocell.
Compaction operation: Use a road roller or other compaction equipment to compact the filler. The degree of compaction should meet the design requirements. During the compaction process, avoid damaging the geocell. (Static compaction) or light vibration compaction methods can be used.
Wall Surface Protection and Drainage Facility Installation
Wall surface protection: According to the project requirements, a protective layer can be set on the wall surface of the geocell retaining wall, such as a concrete panel, geogrid, or vegetation, to enhance the anti-scour ability and durability of the wall surface. If vegetation protection is adopted, fill the geocell with planting soil, sow grass seeds, or lay turf.
Drainage system: Set drainage holes or drainage pipes at appropriate positions of the retaining wall to drain the accumulated water behind the wall and prevent damage to the wall caused by water accumulation. The spacing, diameter, and slope of the drainage holes should meet the design requirements. A filter layer should be set in the drainage holes to prevent the loss of soil particles.
Quality Inspection and Acceptance
Inspection content: Check whether the laying range, spacing, fixing method, and connection method of the geocell meet the design requirements. Conduct a stability inspection of the overall structure of the geocell. Check the degree of compaction of the filler and the smoothness of the drainage system.
Acceptance criteria: Acceptance shall be carried out in accordance with relevant engineering quality acceptance standards and specifications. For unqualified parts, rectification or rework shall be carried out in a timely manner to ensure that the construction quality meets the standards.
