New Parallel Runway of Airport (High Strength Woven Geotextile)
New Parallel Runway of Airport (High Strength Woven Geotextile)
1. Project Background
A new parallel runway is constructed for the airport, located in an estuarine delta. The site consists of thick saturated silt and silty sand with extremely low bearing capacity. The predicted total settlement can reach 2 m, and the natural consolidation period lasts up to 4 years. A solution of hydraulic sand filling platform + basal reinforcement geotextile + staged filling is adopted to meet heavy aircraft load requirements and shorten the construction period.
2. Geotextile Specification & Consumption
Type: High-strength polyester woven geotextile
Specification: PET series, longitudinal tensile strength ≥ 200 kN/m, high modulus; the seam strength complies with design load requirements.
Net laying area: 370,000 m²; wastage factor: 10%, total procurement quantity: 407,000 m²
3. Functions & Performance of Geotextile
✅ Reinforcement + Separation + Stress Distribution
Serving as the main basal reinforcement layer, it restrains lateral extrusion of soft soil and reduces differential settlement. It separates the underlying silt from overlying hydraulically filled sand to prevent sand from sinking into silt. It evenly distributes aircraft wheel loads and the self-weight of fill onto the soft foundation.
✅ Outcome: No mud squeezing or basal instability occurred during filling. The waiting time for preloading consolidation is greatly shortened, ensuring scheduled commissioning of the runway with uniform long-term settlement.
4. Construction Parameters
Laying: Deployed and spliced on water by large floating barges. Pre-sewn in large panels off-site to minimize field overlap; relaxation rate: 1.5%～2%.
Seams: All seams prefabricated in factory, seam strength no less than 80% of parent material; field overlap ≥1.5 m (large-area underwater splicing)
Fixation: Stabilized by overlying hydraulic filled sand, no anchors used. Hydraulic sand covering shall be implemented immediately after laying to avoid long-term UV exposure.
Quality control: Hydraulic filling in separate lifts with strictly controlled filling rate, together with settlement and lateral displacement monitoring.
5. Coordination with Other Measures
High-strength woven geotextile: Basal reinforcement and separation, providing short-term overall stability.
Hydraulic filled sand cushion: Working platform for construction and vertical drainage path.
Staged filling & monitoring: Control loading rate to avoid foundation sliding.
Surface runway structure layer (graded crushed stone + asphalt): Directly bears aircraft wheel loads.
