Road Reinforcement Geocell
Road reinforcement geocell is a strong three-dimensional honeycomb grid material that can be used to strengthen weak soils and reduce pavement settlement. It also has a wide range of other applications, including retaining walls and slope protection.
To examine the behavior of this innovative construction method, researchers conducted moving-wheel tests on four unpaved sections with a base course made of low-volume aggregate and novel polymeric alloy geocells. The results indicate that a geocell-reinforced base can significantly improve pavement performance.
Increased Load Capacity
While planar geosynthetic materials have been used for years to increase load capacity of soil, three-dimensional geocell reinforcement is comparatively new. It provides an effective alternative to traditional methods and offers many advantages including a reduction in the thickness of road base material. This can reduce the construction cost, increase the speed of paving, and improve the performance of the paved surface.
The GEOWEB cellular confinement system increases the bearing capacity of soil layers without increasing the thickness of the base, and it can be utilized in different projects. This system is highly efficient, easy to install, and has a high level of stability. Compared to conventional 2D reinforcement materials, it can decrease the amount of base materials needed by 50% or more.
Model tests of the GEOWEB geocell reinforced section were conducted in a medium-scale loading box that was designed and fabricated by the Department of Civil, Environmental, and Architectural Engineering at the University of Kansas. During the testing, single and multiple geocells were placed in the box. The model testing results indicated that the difference between modeling and experimental settlement values remained below 5% for the reference section.
The results of the model test indicate that geocells can significantly reduce settlement levels, even at a vertical stress level of up to 1750 kPa. However, the settlement reduction potential decreases with the increase in the aperture size of the geocells. This means that it is important to choose the right geocell type when constructing roads using this technology.
Reduced Settlement
Road reinforcement geocells help to distribute the load over a greater area and reduce the pressure on the foundation soil. This reduces the settlement of the roadway and extends its life. This is especially important in areas with poor soil quality.
The honeycomb structure of the Geocell helps to evenly distribute the loads across a larger surface area, reducing the lateral stress on the soil. This can also reduce the damage caused by heavy traffic. The use of Geocells can also save Road reinforcement geocell time on construction projects because they require less excavation than other reinforcement methods. They are also much easier to install than traditional road construction materials.
In addition to the improvement in bearing capacity, Geocells also contribute to a reduction in settlement in the roadbed and pavement. Studies of the effects of Geocells on soil reinforcement by experimental, field, numerical, and analytical methods have found significant improvements in performance.
Compared to the reference section without geocells, the settlements in the sections with 440 mm and 660 mm cell apertures were reduced by 27% and 36% respectively, and the settlement was reduced even more as the geocell height increased. It was observed that the loss in confining pressure was caused by a decrease in the stiffness of the geocell-soil composite and a reduction in the number of cells per unit area as the aperture size was reduced.
Reduced Maintenance Costs
Road reinforcement geocells reduce the amount of materials required for a project. They also eliminate the need for piling and deep excavation methods, which are expensive and can damage subgrades. They can also be used with recycled materials, which is better for the environment. This lowers the cost and makes roads more sustainable.
Geocells have a honeycomb structure that allows for water and oxygen to pass through, which helps prevent erosion and reduce maintenance costs. This means that your roads and parking areas will be safe to drive on even during wet weather.
Another benefit of using Road reinforcement geocells is that they increase the bearing capacity of a road construction. The lateral confinement provided by the geocells increases the shear and bearing strength of the subgrade soil, allowing traffic loads to be carried over it without causing settlement.
The reinforcement effect of geocells is influenced by several factors, including their geometry, configuration, and soil properties. The variation in these parameters affects the performance of geocell-reinforced pavements. The optimum configuration of a geocell depends on the site conditions and the design criteria for the pavement.
The size of the geocell pocket influences the reinforcement efficiency. In a geocell network with smaller pocket sizes, the additional confining stresses developed in the infill soil are greater than those for larger pockets. This result in controlled settlements and heaves, which reduces the risk of structural failure and improves the overall performance of geocell-reinforced road structures.
Increased Lifespan
Using geocells can help to extend the lifespan of the roadbed and reduce the frequency of repairs. The honeycomb structure of the geocells helps to distribute heavy loads more effectively across a wider area, which can reduce the local pressure on the foundation soil, and thus lessen the chance of rutting and settlement in the road surface. This can reduce Geosynthetic clay liner the need for resurfacing or reconstruction of the road, which in turn lowers construction and maintenance costs.
Furthermore, the cellular confinement system of the geocells also increases soil stability by creating a three-dimensional network in the ground, preventing lateral erosion on road slopes. It can also protect the roadbed structure and prevent sand washout on embankments. In addition, the cellular confinement system of the Road reinforcement geocell can help to improve the load-bearing capacity of the roadbed and reduce the road thickness, which lowers overall construction costs.
Sanat Pokharel, Ph.D., P.Eng., Timothy Yii, M.Sc., and Meisam Norouzi are engineers with Stratum Logics Inc in Acheson, Alberta, Canada.
In this study, the performance of a geocell-reinforced unpaved road was investigated under a constant traffic load. The results showed that the use of geocells significantly reduced the permanent deformation of the road layer. This result was consistent with the fragility analysis method developed by Giroud and Han (2004) for planar geocell reinforcement. The comparison between the experimental and modeling results was within 5% for the reference section and up to 30% for the geocell-reinforced sections at the maximum stress of 1000 kPa.
