Base Stabilization is a process that uniformly mixes and incorporates stabilizing agents into an aggregate base material to produce a stabilized layer, increasing the structural integrity or quailty of the base layer. Base stabilization can be used in new construction or reconstruction. Mixing of the stabilizing agent with base material can take place at a central location or in-place. When mixed at a central location, a pugmill mixer is typically used to mix the stabilizing agent with the base material and then the material is hauled to the site where it is placed and compacted. With in-place operations, new aggregate can be spread on an existing subgrade and the stabilizing agent added and mixed in-place, similar to FDR. With reconstruction, any existing materials above the base layer are removed and the base layer stabilized in-place similar to FDR.
From civil & geotechnical engineers, to supplier and contractor, a qualified competent team is critical to success of the project
The equipment used to perform Base Stabilization will vary from contractor to contractor, but no matter how configured, the equipment performs the same general steps. The equipment requirements for Base Stabilization depend on the specifics of the project but generally consists some or all of the following:
Chemical Stabilization is achieved with the addition of cement (portland or hydraulic), lime (hydrated or quicklime), self-cementing class C fly ash, class F fly ash (when used in combination with other additives), cement kiln dust (CKD), lime kiln dust (LKD), calcium chloride, magnesium chloride or proprietary products to the pulverized materials.
Bituminous Stabilization is accomplished with the addition of emulsified asphalt or foamed (expanded) asphalt to the pulverized materials.
Base Stabilization + Single or Double Chip Seal: A surface course is required over base stabilized sections and where the pavement structure is sufficient to carry the anticipated loads, chip seals are very economical.
Base Stabilization + Micro or Slurry Surfacing: Where the reclaimed pavement structure is sufficient to carry the anticipated loads micro or slurry surfacing are additional economical surfacing options.
Base Stabilization + Asphalt Surface: To increase the structural capacity of the pavement structure, an asphalt mix can be placed over the stabilized base layer.
Base Stabilization + Cold Mix Surface: For low volume pavement applications, a cold asphalt mix or CCPR asphalt mix can be placed over the stabilized base layer. A seal coat may be required to prevent moisture infiltration.
Base Stabilization + Concrete Surface: A stabilized base layer can be used as a non eroding base in a rigid pavement structure.