Roadbed Stabilization for Eastern Africa Highway Project
PROJECT DESCRIPTION
Taian Changfeng Synthetics Co., Ltd. (Changfeng) was requested to deliver a high-performance geosynthetic solution for an upgrade section of a major national highway in Eastern Africa. The construction corridor traversed an alluvial plain characterized by extremely soft subgrade (CBR < 2%) consisting of high-plasticity clay and silt.
During the wet season, this subgrade lost its shear strength entirely. Heavy construction logistics, including fully loaded three-axle dump trucks, experienced severe sinking, with wheels embedding up to 40 cm into the saturated soil. The client required a reliable, fast-to-deploy, and structurally robust soil reinforcement design capable of stabilizing the roadbed, resisting extreme axle-load stress, and ensuring a service life of over 15 years under high-precipitation conditions.
RELATED PRODUCTS
Long Fiber Nonwoven Geotextile
OUR SOLUTION
To overcome the severe hydrological challenges and weak subgrade bearing capacity, Changfeng proposed an integrated, multi-layered geosynthetic reinforcement system combining Changfeng High-Performance Nonwoven Geotextile and Changfeng HDPE Geocell Cellular Confinement System.
The engineering design was calculated to withstand the heavy axle loads:
1. Separation & Filtration Layer
Changfeng 300g/m² Filament Nonwoven Geotextile was laid directly onto the prepared weak subgrade. This layer acted as an engineered barrier, preventing the migration of fine subgrade clay into the premium base aggregate while facilitating rapid lateral water drainage to relieve pore water pressure.
2. Confinement & Reinforcement Layer
Changfeng Textured & Perforated HDPE Geocell (150mm height, 445mm weld spacing)
was deployed over the geotextile. Utilizing a high-strength connection interlocking system, the geocell network was expanded and filled with local well-graded crushed gravel.
This hybrid design created a rigid, semi-flexible slab effect (often referred to as the “beam effect”). The three-dimensional lateral confinement of the Changfeng Geocell restricted aggregate lateral displacement under heavy wheel loads, distributing concentrated wheel pressures over a much wider area. Consequently, the required structural aggregate base thickness was safely reduced by over 52%, substantially cutting down on material importing costs and construction time.
A total of 15,000 m² of Changfeng geosynthetics were successfully supplied and installed, creating an exceptionally stable, all-weather hauling and transit corridor.
PRODUCTS USED
1. Changfeng HDPE Geocell Cellular Confinement System
Premium Material Quality
- Manufactured from 100% virgin High-Density Polyethylene (HDPE) with advanced UV-resistant stabilizers, ensuring excellent chemical resistance, environmental stress cracking resistance (ESCR), and a service life exceeding 20 years in harsh soil environments.
Textured & Perforated Cells
- High-friction textured cell walls prevent aggregate slippage, while specialized perforations facilitate lateral drainage and joint lock-up, maximizing load transfer efficiency.
Optimized Seam Strength
- Features high ultrasonic seam-weld strength (exceeding 1420 N per 100 mm), allowing the interconnected cell network to withstand high tension and dynamic loading without splitting.
Rapid Deployment
- Accordion-style folding sections allow flat-packed shipping for bulk cargo efficiency, expanding on-site with simple high-strength pins, dramatically reducing installation timelines and heavy machinery dependencies.
2. Changfeng High-Performance Filament Nonwoven Geotextile
Superior Filtration & Separation
- Needle-punched long-fiber polyester (PET) structure offers optimal pore size distribution, keeping fine clay subgrade separated from structural gravel while maintaining continuous high water flow.
High Puncture and Tensile Strength
- Possesses excellent mechanical properties to survive installation damage and withstand the sharp, jagged edges of angular crushed stone base aggregates during compaction.
Hydrological Performance
- Excellent cross-plane water permeability and in-plane transmissivity swiftly dissipate excess pore pressure, preventing the subgrade from liquefying or softening during seasonal downpours.
