The leading cause of pavement and roadway failure in the U.S. is contamination of the aggregate base and the resulting loss in aggregate strength. When aggregate is placed on a subgrade, the bottom layer becomes contaminated with soil. Over time, traffic loading and vibration punches pavement base aggregate into the soil and causes silt and clay to migrate upward. On wet sites, construction traffic causes pumping of wet subgrade soils into overlying aggregate. All of these conditions decrease the effective aggregate thickness, destroying the road support and reducing roadway performance and life.

Another major contributor to roadway deterioration is water beneath a pavement, which softens subgrade soil and destroys pavement structural capacity. A pavement with a base which becomes saturated as little as 10% of the time will only have 50% of the life of a pavement where water is kept out of the base. Most of this water enters through cracks and pores in the pavement surface.

Geotextiles provide four important functions which enhance roadway performance: separation, stabilization, reinforcement and drainage. The geotextile you select depends on which functions are suited to your project.

DX2 supplies pavement designers and contractors with the widest selection of geosynthetic interlayer products available today. Mirafi^® Mirapave forms an impermeable membrane that prevents the penetration of surface water through the pavement and also provides a stress relieving layer which inhibits reflective crack growth. Mirafi^® Mirapave can also be used with chip seal surface treatments to improve the performance of the rehabilitated pavement, when installed with a tack coat between the pavement and the chip seal.

Both woven and nonwoven geotextiles provide long-term separation of the aggregate base from the subgrade soil. By separating these two materials, the geotextile maintains the original thickness of the roadway aggregate. This is the most important geotextile function for roads, particularly when constructing on weak to moderate strength subgrade soils (CBR<7). The geotextile also makes it possible to use a more open-graded, high permeability pavement aggregate base which improves rapid drainage. By decreasing aggregate loss and increasing its permeability, you substantially increase roadway performance and life while decreasing maintenance costs.

Higher strength woven and nonwoven geotextiles provide stabilization in addition to the primary function of separation. Through stabilization, a geotextile can increase the effective bearing capacity of low strength subgrade soils. A stabilization geotextile reduces subgrade pumping, over-excavating and required aggregate thickness. The Installation Guidelines For Geosynthetics Used In Subgrade Stabilization provides a detailed guide for installing geotextiles for stabilization.

Stabilization geotextiles substantially reduce construction costs for paved and unpaved roads. For example, unpaved road aggregate thickness can be reduced by as much as 30% to 50% when a stabilization geotextile is used.

Separation, stabilization and reinforcement are needed for construction over weak subgrade soils (soaked CBR <2%). High-modulus, woven reinforcement geotextiles provide the added benefit of subsurface drainage. These products are ideal when water is expected to flow from the subgrade soil into to the aggregate base.
DX2 offers a complete line of Mirafi® woven and nonwoven geotextiles to improve the performance of flexible pavement roads, unpaved roads, access roads, parking lots, airports, loading docks and storage areas. These fabrics are installed beneath thousands of lane miles of roadway each year. Because the product you select is dependent upon construction conditions, DX2 can assist you in selecting the geotextile that is appropriate for the job.

Roads/Airfields

In road and airfield pavements, a Mirafi^® geosynthetic is placed on top of soft subgrades prior to placement of the granular subbase layer. The geosynthetic prevents the loss of the granular subbase material into the soft subgrade, maintaining the structural integrity of the pavement. The use of Mirafi^® thus extends the maintenance-free life of pavements constructed on soft subgrades.

#Mirafi^® X-Series
#Mirafi^® HP-Series
#Mirafi^® N-Series

In railway tracks, our product is placed between the existing formation and the ballast layer to prevent the subgrade from pumping into the ballast layer, thereby maintaining structural integrity. The use of a geosynthetic significantly increases the periods between track maintenance with considerable savings in labor and material costs.

#Mirafi^® X-Series
#Mirafi^® HP-Series
#Mirafi^® N-Series

In earthworks construction, the Mirafi^® geosynthetic is placed between two different kinds of fill to ensure that intermixing does not occur during placement and compaction. This maintains the distinct layer boundaries between dissimilar adjacent earthfill materials, maintaining their structural integrity.

#Mirafi^® X-Series
#Mirafi^® HP-Series
#Mirafi^® N-Series

Mirafi^® geosynthetics are used as filters for subsurface drainage to enhance the performance of pavement and earthworks structures. They allow the groundwater to pass into the subsurface drain without eroding the soil, and thus ensure long-term performance.

Mirafi^® N-Series