Paved and Unpaved Roads

Paved and Unpaved Road Construction

Well built and maintained paved and unpaved roads are essential for efficient transportation, vital for a thriving economy. They reduce travel times, fuel consumption, transportation costs and increase safety. This ultimately leads to enhanced productivity and efficiency.

With traditional methods, building and maintaining roads [especially paved roads] are associated with costly delays, requires large amount of aggregates and are overall expensive. However, with NPA geocells, both types of roads can be designed and built to reduce cost and quantity of aggregate, require less labour, time and future maintenance.

Paved and Unpaved Roads built Sustainably

There are many variables to consider when undertaking roadway design for which Stratum prioritizes sustainability first and foremost, integrating the use of NPA geocell technology in our designs.

However, apart from sustainable road building in both paved and unpaved roads, Stratum takes the following into account to achieve the optimal road solution:

  • Design life calculation [projected traffic load and desired length of service]
  • Geometric design
  • Traffic flow
  • Structural pavement

With a multitude of engineering, environmental and economic advantages, geosynthetic soil stabilization solutions offer a win-win scenario for engineers, planners and contractors in any kind of road construction project.

Paved Road Designs

Paved roadways fall into two categories: those surfaced with flexible pavement and those utilizing rigid pavement components. Flexible paved roads include asphalt-surfaced and/or chip-sealed roads. Hot Mix Asphalt (HMA) is commonly used on major urban streets and highways and delivers the smooth riding experience drivers have come to expect. Rigid pavements typically include concrete components.

Chip seal is an alternative surface treatment that combines one or more layer(s) of asphalt with one or more layer(s) of fine aggregate. Chip seal treatments are typically used on rural roads carrying lower traffic volumes, and are constructed by embedding finely graded aggregate into a thin base of hot bitumen or asphalt.


Reinforced Paved Roads

In either case, to achieve the desired design life of the road, the appropriate base and sub-base layers must be engineered to meet the structural requirements. Where the underlying soil is weak, it must be suitably stabilized and reinforced to provide adequate load support. Incorporating geosynthetic components into the road design has been shown to dramatically improve base and sub-base layers while utilizing existing soil, thus reducing the need for costly infill material such as gravel or sand. The potential benefits of geosynthetically reinforced road construction can include:


  • Reduced asphalt layer required
  • Reduced aggregate thickness required (in base or sub-base)
  • Increased long-term performance
  • Reduced road construction and maintenance costs
  • Reduced carbon emissions and carbon tax liabilities

Unpaved Road Designs

It is estimated that nearly 80% of the world’s roads are unpaved. These may include gravel roads or other non-paved surface roads, many of which are built over weak or saturated soils which require significant soil stabilization and road base reinforcement. In these situations, geosynthetic components such as NPA geocells provide three-dimensional reinforcement to improve the modulus of the road base layer. NPA geocells have been proven to be more durable and more cost-effective than any other ground stabilization solution for unpaved road construction. Geocell technology, when employed to increase the modulus of the base layers, results in durable, low-maintenance roads capable of supporting the heaviest loads in the most remote and difficult environments such as for oil & gas production, mining, logging, military operations and more.

Geosynthetics also present an ideal soil stabilization solution for unpaved gravel roads of other functions, such as service, haul, access, and secondary feeder roads that must be built over soft soils. NPA geocells can stabilize soft subgrade, reinforce the road base and help prevent cracking or other degradation of the road surface. The use of innovative geosynthetic technology allows us to make vast improvements in road construction over conventional methods. The addition of NPA geocells in road construction results in more sustainable roads and reduces both road construction and maintenance costs.