APPENDIX D
Results of Contractor Survey on Full-Depth Reclamation Construction Practices

The contractor survey questionnaire and results are presented in this appendix. The following companies participated in this survey: California Nevada Cement Association, Pavement Recycling Systems, Mountain States Constructors, Inc., Ruston Paving Co., Inc., Slurry Pavers Inc., SurfaceCycle, Atlanta Paving and Concrete Construction, Mt. Carmel Stabilization Group, Inc., Recon Construction Services, Inc., and E. J. Breneman, L.L.C.

Part A: State-of-the-Practice Related to the Use of Full-Depth Reclamation

Question 1: Has your company conducted (within the past 5 years) Mechanical FDR or FDR pavement rehabilitation projects?

• Both Mechanical FDR and FDR
• Mechanical FDR only
• FDR only
• Our company has not conducted Mechanical FDR or FDR projects within the past 5 years

Long Description.

The data is as follows. Both mechanical FDR and FDR, 11. Mechanical FDR only, 0. FDR only, 0. Mechanical FDR or FDR not used, 0.

Question 2: How many years of experience does your company have conducting FDR? (select best option):

• <5
• 5–10
• 10–20
• >20

Long Description.

The data is as follows. Less than 5, 0. 5 to 10, 1. 10 to 20, 4. More than 20, 6.

Question 3: What is the approximate number of lane miles per year that are recycled by FDR by your agency? (select best option):

• <50
• 50–100
• >100
• Unsure

Long Description.

The data is as follows. Less than 50, 1. 50 to 100, 2. More than 100, 7.

Question 4: On which roadway types (average daily traffic levels) does your company typically carry-out FDR? – select all that apply:

• <2,500
• 2,500–5,000
• 5,000–10,000
• 10,000–20,000
• 20,000–30,000
• >30,000
• Unsure

Long Description.

The horizontal axis for the number of agencies ranges from 0 to 12 in increments of 2. The vertical axis for average daily traffic (ADT) lists different categories. The data is as follows. Less than 2,500, 10. 2,500 to 5,000, 8. 5,000 to 10,000, 8. 10,000 to 20,000, 5. More than 30,000, 5. 20,000 to 30,000, 4. Unsure, 1.

Question 5: When conducting FDR, what are the most common primary distress(es) in the existing pavement? – select all that apply:

• Base failure
• Fatigue cracking
• Longitudinal and transverse cracking
• Potholes
• Rutting
• Unsure
• Other (please specify)

Long Description.

The horizontal axis for the number of agencies ranges from 0 to 12 in increments of 2. The vertical axis lists different categories. The data is as follows. Base failure, 11. Rutting, 9. Fatigue cracking, 9. Potholes, 8. Longitudinal and transverse cracking, 7.

Question 6: Before conducting FDR, does your company perform a pre-design investigation? (select best option):

• Yes – always
• Yes – if the agency requires it
• No
• Unsure

Long Description.

A pie chart shows the data as follows. Yes, if the agency requires it, 9. Yes, always, 2. No, 0.

Question 7: When conducting a pre-design investigation for FDR, what testing is conducted? – select all that apply:

• Evaluation of strength/stiffness of layers of existing pavement structure (such as, Falling Weight Deflectometer or Dynamic Cone Penetrometer testing)
• Evaluation of the thickness of layers of existing pavement (such as Ground Penetrating Radar testing or core drilling)
• Sampling of material (for verification of layers for understanding lower layer condition from cored samples)
• Other (please specify)

Long Description.

The horizontal axis for the number of agencies ranges from 0 to 12 in increments of 2. The vertical axis lists different categories. The data is as follows. Sampling of materials, 11. Evaluation of the thickness of layers, 6. Evaluation of strength or stiffness of layers, 4. Other, 1.

Question 8: Which of the following stabilizing agents or additives are generally used for an FDR project by your company? – select all that apply:

• Calcium chloride
• Cement
• Emulsified asphalt
• Foamed asphalt
• Fly ash
• Lime (or lime kiln dust)
• Quarry by-products
• Other (please specify)

Long Description.

The horizontal axis for the number of agencies ranges from 0 to 12 in increments of 2. The vertical axis lists different categories. The data is as follows. Cement, 11. Lime or lime kiln dust, 5. Emulsified asphalt, 4. Foamed asphalt, 3. Fly ash, 3. Quarry by-products, 2. Calcium chloride, 1. Other, 1.

Part B: State-of-the-Practice Related to the Use of Stabilizing Agents in Full-Depth Reclamation

Question 9: Who determines/specifies the stabilizing agent type in FDR applications? (select best option):

• Agency determined
• Contractor determined based on agency requirements
• Contractor determined independently
• Unknown
• Other (please describe briefly)

Long Description.

The horizontal axis for the number of agencies ranges from 0 to 8 in increments of 2. The vertical axis lists different categories. The data is as follows. Agency determined, 7. Contractor determined based on agency requirement, 3. Contractor determined independently, 0. Other, 1.

Question 10: What is the primary factor your company uses to determine which stabilizing agent to use in an FDR project? (select best option):

• Traffic level
• Availability of material
• Historic use or past performance
• Life cycle cost analysis
• Mix design results
• Other (please specify)

Long Description.

The horizontal axis for the number of agencies ranges from 0 to 4 in increments of 1. The vertical axis lists different categories. The data is as follows. Mix design results, 3. Traffic level, 0. Availability of material, 0. Historic use or past performance, 0. Life cycle cost analysis, 0.

Question 11: Who determines/specifies the stabilizing agent dosage in FDR applications? – (select best option):

• Agency determined
• Contractor determined based on agency requirements
• Contractor determined independently
• Unknown
• Other (please describe briefly)

Long Description.

The horizontal axis for the number of agencies ranges from 0 to 6 in increments of 1. The vertical axis lists different categories. The data is as follows. Contractor determined based on agency requirements, 4. Agency determined, 2. Contractor determined independently, 0. Other, 5.

Question 12: How does your company determine the stabilizing agent dosage in an FDR project? – (select best option):

• Fixed dosage based on stabilizing agent type (please briefly describe):
• Dosage is determined based on our methodology (please briefly describe):
• Based on agency guidelines
• Other (please specify)

Long Description.

The data is as follows. Fixed dosage based on stabilizing agent type, 0. Dosage is determined based on our methodology, 2. Based on agency guidelines, 1. Other, 1.

Part C: State-of-the-Practice Related to Post-Construction for Full-Depth Reclamation

Question 13: What properties does your company evaluate during FDR construction for quality control (QC)? – select all that apply:

• Moisture content
• Compaction (in-situ density)
• Gradation of pulverized material
• Mechanical characterization
• Stabilizing agent amount
• Depth
• Cross-slope
• Surface properties (such as smoothness or deviation from a straight edge) of the FDR layer (post-compaction, pre-overlay)
• Unknown
• Other (please specify)

Long Description.

The horizontal axis for the number of agencies ranges from 0 to 10 in increments of 2. The vertical axis lists different categories. The data is as follows. Moisture content, 9. Compaction (in-situ density), 9. Gradation of pulverized material, 9. Stabilizing agent amount, 9. Depth, 9. Cross-slope, 7. Surface properties of FDR layer (post-compaction, pre-overlay), 5. Mechanical characterization, 2. Other, 2.

Question 14: How does your company determine when to allow traffic or place surfacing on the FDR layer? – select all that apply:

• A set amount of time
• Raveling resistance (e.g., short-pin raveling test)
• Shear resistance (e.g., long-pin shear test)
• Modulus/stiffness criteria
• Moisture content criteria
• Agency determines timing
• Other (please specify)

Long Description.

The distribution is with respect to how it is determined when traffic or surfacing placement is allowed on a newly constructed FDR layer. The horizontal axis for the number of agencies ranges from 0 to 5 in increments of 1. The vertical axis lists different categories. The data is as follows. A set amount of time, 4. Agency determines timing, 4. Moisture content criteria, 2. Modulus slash stiffness criteria, 1. Raveling resistance (for example, short-pin raveling test), 0. Shear resistance (for example, long-pin shear test), 0. Other, 1.

Question 15: When performing FDR, does your company routinely perform any treatments to reduce the potential for cracking in asphalt overlays on FDR?

• Yes (please briefly describe which treatments)
• No
• Unsure

Long Description.

A pie chart shows the data as follows. Yes, 6. No, 4.

Part D: Identification of Challenges and Future Plans

Question 16: What challenges to starting (or continuing) to successfully perform FDR has your company experienced?

• Lack of agency experience
• Lack of contractor expertise
• Lack of mix design methods and engineering-based design procedures
• Lack of tests and criteria to determine dosage of stabilizing agents and/or performance
• Poor performance of previously constructed FDR rehabilitated pavements
• No significant challenges
• Other (please describe briefly)

Long Description.

The horizontal axis for the number of agencies ranges from 0 to 8 in increments of 2. The vertical axis lists different categories. The data is as follows. Lack of agency experience, 7. Poor performance of previously constructed FDR, 4. Lack of contractor expertise, 3. Lack of mix design methods and design procedures, 2. Lack of criteria to determine stabilizing agent dose, 1. No significant challenges, 1. Other, 6.

Question 17: If you have any additional information or thoughts you would like to share regarding this topic, please do so here:

• (please provide additional information or thoughts regarding FDR)

Transportation Research Board
500 Fifth Street, NW
Washington, DC 20001