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Full Depth Reclamation

来源：发布日期：2006-7-14

WHAT PRODUCTION CAN BE EXPECTED?
Due to the wide array of additives, equipment available and varying roadway distress addressed using Full Depth Reclamation (FDR) , it is difficult to suggest a single expected production rate. Production rates may vary from 300sy/hr to 1,200sy/hr, on average, based on variables such as pavement composition, depth of material and gradation.

Top H0W SOON CAN YOU DRIVE ON RECLAIMED MATERIAL?
With the new breakthroughs in chemical stabilizers alone and in combination with bituminous additives, cure times can be greatly reduced, allowing moderate traffic to resume only minutes after compaction. Traffic can also be maintained during the process with adequate project management.

Top HOW DO YOU DETERMINE WHAT (IF ANY) ADDITIVE(S) SHOULD BE USED?
In recent years, we have examined economic and engineering guidelines for the evaluation, including proper in-situ mix designs, of selected additives. Guidelines for selecting stabilizing additives are available for viewing in the new Full Depth Reclamation brochure available through your local ARRA Contractor Member. (Note: A properly-engineered mix design in conjunction with both on-site construction monitoring and the contractor''s experience, all culminate in the proper additive selection).

Top HOW LONG WILL RECLAIMED ROADS LAST?
As with any typical road construction project (either new or reconstruction), proper design and project construction monitoring is of utmost importance to assure a life-cycle representative of the design. With those elements in place, a reclaimed road should have the same life-cycle expectancy as a road constructed with virgin materials.
Top EXPLAIN THE DIFFERENCE BETWEEN CIR AND FDR.
The main difference between Cold In-Place Recycling (CIR) and Full Depth Reclamation (FDR) is that FDR incorporates both the bound asphaltic layers and a predetermined portion of the underlying base materials used in the initial construction. CIR incorporates only the bound asphaltic layers for recycling. Therefore, FDR is the only methodology other than total reconstruction which addresses base deficiencies.

Top CAN YOU RECLAIM A ROAD ABSENT ANY EXISTING ASPHALT (i.e. GRAVEL ROADWAYS)?
Yes. Bituminous and chemical (cement, lime, calcium chloride, fly ash, etc.) stabilization/reclamation can be utilized solely or in combination as methods of FDR in the absence of any in-sitsu asphaltic materials. An asphaltic surface treatment such as chip seal or overlay should then be used to "seal off" the reclaimed layer and provide a running surface for vehicles.

Top EXPLAIN THE DIFFERENCE IN TERMINOLOGY BETWEEN SOIL STABILIZATION AND FULL DEPTH RECLAMATION.
Soil stabilization can be defined as a chemical or mechanical treatment designed to increase or maintain the stability of a mass of soil or otherwise to improve its engineering properties. FDR incorporates or reclaims in-sitsu pavement materials installed in the initial construction and/or through the years of improvements and blends those materials together to re-establish pavement layer integrity.

Top EXPLAIN THE DIFFERENCE IN COST OF FDR vs. CONVENTIONAL RECONSTRUCTION METHODS.
Substantial savings may be gained on any given project. FDR utilizes all or nearly all in-sitsu materials in-place and minimal supplemental materials are delivered to the site. There we also cost-savings in the mining of virgin materials needed for conventional reconstruction, as well as benefits reflected in time savings and environmental concerns, which make FDR even more attractive than conventional reconstruction.

Top CAN MY EXISTING ROAD BE WIDENED USING FDR METHODOLOGY?
Yes. It is common to widen using FDR by incorporating shoulder material into the pulverized roadway materials. One can, through FDR, create a homogeneous reclaimed base material throughout the pavement cross section by utilizing the pulverized material of the interior of the roadway and pushing this material into the excavated areas of widening. Supplemental aggregates could also be incorporated to adjust the desired depth and gradation of the recycled mat.

Top CAN FDR BE PERFORMED ON AN EXISTING CURB/GUTTER STREET?
Yes. However, material management inside the curbs becomes a critical issue in both the bid/design construction of the improvements. Consideration should be given to the geometry of the roadway prior to and after FDR to evaluate the need to remove or add material so that the reclaimed material and new surface course meet the existing gutter. Removal of surplus material and a thicker than normal leveling course should be considered as part of the project. A design/construction suggestion would be to remove material after pre-pulverization to insure adequate blending of the bound asphaltic materials with underlying granular materials. This practice will retain the ＆#118alue of the residual asphalt binders in the upper layers.

Top WHAT TYPES OF PROBLEMS CAN FDR CORRECT?
FDR is an option to improve a wide variety of pavement distress signs. Some of the distress signs that FDR can fix are frequent deep cracking (transverse or lateral), reflective/alligator cracking, heavy pothole patching, severe rutting/shoving, parabolic shape and insufficient base strength. The key to FDR is that all the distress types mentioned above are eliminated by pulverization and subsequently strengthened with available stabilizers, if required.