Asphalt Reinforcement Products

Asphalt Reinforcement

Solution Overview

Cracking in the asphalt layer reduces the stiffness of a pavement and allows water to ingress, weakening the foundation layer and subgrade, and leading both to further deterioration and permanent loss of strength. Conventional rehabilitation procedures prescribe placing an asphalt overlay on top of the existing surface or after first planning off the upper asphalt layer – mill and fill. Although this can provide some additional service life, the appearance of cracks is only slowed, and they quickly re-appear. With this approach you will fight a constant battle with pavement maintenance that can never be won...

However when an asphalt interlayer is installed, overlay performance is drastically improved, which significantly reduces the maintenance cost per kilometre, per year. Tensar offers a family of asphalt interlayer products that can help and our team is ready to support you in your selection of the best fit for your project.


What causes the cracking?

Cracking can grow from existing cracks or joints in the substrate (reflective cracking) or be induced by thermal movement of substrates or expansion and shrinkage of subsoils.  Excessive flexing of the pavement under traffic loading can also lead to fatigue cracking in the asphalt.  

How does an asphalt interlayer help?

Asphalt interlayers can provide a barrier to moisture ingress and also offer stress relief and reinforcement, to control cracking in the asphalt surfacing.  Reinforcing asphalt interlayers can also improve pavement life by delaying the onset and propagation of fatigue cracking.

What are the functions of an interlayer?

Interlayers can provide:

  • A barrier – to prevent the ingress of moisture
  • Stress relief  - To allow some movement between layers and thus relieve stress build-up
  • Reinforcement – to provide tensile strength and stiffness to an asphalt layer.

What are the Types of Asphalt Interlayer?

There are different types of of interlayer that perform one or more of the potential interlayer functions.

  • Paving fabrics are designed to absorb bitumen from the intallaiton process to provide barrier and stess relief functions. There are different forms of fabric, the most common being made from non-woven polypropylene yarn.

  • Grid type interlayers have open apertures to allow bonding of the overlay to the substrate. The grid structure is typically coated woven glass fibre.

  • Structural Grid types have a higher rib profile to enable some interlock between the overlay and the grid. The grid is typically a polpropylene structurewith integral junctions.

  • Composite Interlayers combine a paving fabric with a grid or structural grid to offer multiple functionality.

How does Tensar compare to the competition?

Tensar's Foundation and Embankment products are proven, high-performance solutions that offer significant benefits over alternative solutions.

What are Tensar asphalt interlayers?

Tensar has a range of asphalt interlayer geogrids and composites, designed to interact with the bitumen bound layer. These products add tensile stiffness, limit strains and reduce crack development and size. Composite interlayers comprise a geogrid bonded to a fabric and together they provide reinforcement and act as a Stress Absorbing Membrane Interlayer (SAMI) and a moisture barrier.