Guide to the Investigation and Remediation of Distress in Flexible Pavements

Transcription

1 Guide to the Investigation and Remediation of Distress in Flexible Pavements Presentation for: 2004 Annual Meeting of the Transportation Research Board Based on Study Funded by: California Dept. of Transportation

2 Authors Mike Cook, P.E. (Caltrans) Steve Seeds, P.E. (APTech) Haiping Zhou, P.E., PhD. (MACTEC) Gary Hicks, P.E., PhD. (MACTEC)

3 Why did we need this? Caltrans 12 autonomous districts Has lost a lot of experience Staff amenable to new technology Some practices have become outdated Need for standardized approaches that address typical flexible pavement problems

4 Purpose of Presentation Identify documentation Review basic process Highlight features Share information

5 Documentation Office Manual Detailed reference Limited production Field Manual Assumes familiarity with Office Manual Contains all primary tools Assists field personnel

6 Overview of Guide Introduction Types of Flexible Pavements Hot-Mix Asphalt Surface Treatments Composite (HMA over PCCP) Factors Affecting Pavement Distress and Performance

7 Environment Traffic Pavement Performance Pavement Materials Subgrade Soil

8 Overview of Guide Introduction Types of Flexible Pavements Factors Affecting Pavement Distress and Performance Types of Pavement Distress and Their Mechanisms

9 Pavement Distress Types Typical distress types for both HMA pavements and surface treatments HMA Cracking, Deformation, Deterioration, Mat problems Surface Treatments Seal Coats, Slurry Seals/Microsurfacing Distresses are consistent with Caltrans Condition Survey Procedure

10 Distress Types Covered

11 Pavement Distress Mechanisms Distress Type Wheel Load Climate Temp. Moist. Mtls. Rutting Fatigue Cracking Thermal Cracking Top Down Cracking Stripping Reflection Cracking

12 Example Illustration of Distress Mechanism (Rutting)

13 Overview of Guide Introduction Types of Flexible Pavements Factors Affecting Pavement Distress and Performance Types of Pavement Distress and Their Mechanisms Investigation of Distress

14 Main Objective of Process: Identify and address the cause of the problem, not just the symptom.

15 Flowchart of Process Overall Problem Possible Investigation Requirements Records Review Field Distress Survey Structural Evaluation Field Sampling and Testing Lab Testing Data Analysis Probable Cause(s)

16 Typical Distresses and Possible Causes Overall Problem Possible Causes of Distress Construction Structural Geometric Materials Climate Traffic Mix Design Design Design Distress Type Distress Category Low-Strength or Low-Stability Mix Poor Mix Gradation Low Asphalt Content High Asphalt Content Low Air Void Content High Air Void Content Improper Fines Content Tender Mix Segregated Mix Poor Surface Preparation Excess/Insufficient Prime/Tack Improper Crack Sealing Techniques Improper Compaction Techniques Excess Moisture in Mix Low HMA Thickness Low Base/Subbase Thickness Poor Subgrade Compaction Poor Base/Subbase Compaction Poor Base/Subbase Gradation High Asphalt Binder Viscosity Low Asphalt Binder Viscosity Temp. Susceptible Asphalt Binder Rapid Aging Asphalt Binder Moisture Sensitive Mix Poor Aggregate Durability Poor Aggregate Soundness Poor Aggregate Cleanness High Exposure to Moisture Cool/Cold Prevailing Temperatures Hot Prevailing Temperatures Freeze-Thaw Cycling Large Daily Temperature Cycles High Traffic Volume High ESAL Truck Volume Exposure to Studded Tires/Chains Inadequate Pavement Structure Poor Material Selection Poor Drainage Narrow or Non-Existent Shoulder Narrow Lane Width Excessive Horizontal Geometry Longitudinal Fatigue Transverse Reflective Block Edge Rutting Corrugation Shoving Depression Overlay Bumps Delamination Potholes Patching Raveling Stripping Polished Aggr Pumping Segregation Checking Bleeding Mat Problems Deterioration Deformation Cracking Legend: Common cause of distress Occasional cause of distress

17 Typical Distresses and Possible Causes Low-Strength or Low-Stability Mix Poor Mix Gradation Low Asphalt Content High Asphalt Content Low Air Void Content High Air Void Content Improper Fines Content Distress Type Construction Mix Design Tender Mix Segregated Mix Distress Category Longitudinal Fatigue Transverse Reflective Block Edge Cracking Common cause of distress Occasional cause of distress

18 Possible Data Review/Requirements Distress Structural Field Sampling & Laboratory Testing (General Material Characteristics) Records Review Survey Evaluation Testing Methods Unbound Mat'ls Bound Materials (Strength-Related) Design Reports Plans and Specifications QC/QA Records As-Built Drawings Lab Material Test Results Past Surveys/NDT/Sampling Results Maintenance/Repair Histories Traffic Data Environmental/Climate Records PMS Reports Windshield Survey Detailed Distress Survey Nondestructive Testing Evaluation of NDT Uniformity Struct. Capacity Eval. (Caltrans) Struct. Capacity Eval. (Backcalc.) Coring Auger Base, Subbase and/or Subgrade Shelby (Push) Tube Test Pit (Trench) Dynamic Cone/Standard Penetrometer Soil Classification Gradation Moisture Content Density Density Asphalt Content Air Void Content Asphalt Binder Viscosity Asphalt Temperature Susceptibility Aggregate Gradation Coarse Aggregate Abrasion Aggregate Durability Aggregate Soundness Moisture Sensitivity R-Value (Unbound Materials) Indirect Tensile (Bound Materials) Resilient Modulus (Fine/Coarse Matls) Modulus (Asphalt Mixtures) Possible Causes of Distress Low Strength or Low Stability Mix Poor Mix Gradation Low or High Asphalt Content Low or High Air Void Content Improper Fines Content Tender Mix Segregated Mix Surface Prep./Excess/Lack Prime/Tack Improper Crack Sealing Techniques Improper Compaction Techniques Excess Moisture In Mix Low HMA Thickness Low Base/Subbase Thickness Poor Subgrade Compaction Poor Base/Subbase Compaction Poor Base/Subbase Gradation Low or High Binder Viscosity Temp. Susceptible Asphalt Binder Rapid Aging Asphalt Binder Moisture Sensitive Mix Poor Aggregate Durability Poor Aggregate Soundness Poor Aggregate Cleanness High Exposure to Moisture Cool/Cold Prevailing Temperatures Hot Prevailing Temperatures Freeze-Thaw Cycling Large Daily Temperature Cycles High Traffic Volume High ESAL Truck Volume Exposure to Studded Tires/Chains Inadequate Pavement Structure Poor Material Selection Poor Drainage Narrow or Non-Existent Shoulders Narrow Lane Width Excessive Horizontal Geometry Geometric Design Structural Design Traffic Climate Materials Construction Mix Design Legend: Typical test or data requirement Occasional test or data requirement

19 Possible Data Review/Requirements Distress Records Review Survey Structural Evaluation Design Reports Plans and Specifications QC/QA Records As-Built Drawings Lab Material Test Results Past Surveys/NDT/Sampling Results Maintenance/Repair Histories Windshield Survey Detailed Distress Survey Nondestructive Testing Evaluation of NDT Uniformity Struct. Capacity Evaluation Possible Causes of Distress Low Strength or Low Stability Mix Poor Mix Gradation Low or High Asphalt Content Low or High Air Void Content Improper Fines Content Tender Mix Segregated Mix Mix Design Construction Typical test or data requirement Occasional test or data requirement

20 Use of Selection Tables Overall Problem (by Distress Category and Type) Possible Causes (by General Category) Possible Data Requirements

21 Overview of Guide Introduction Types of Flexible Pavements Factors Affecting Pavement Distress and Performance Types of Pavement Distress and Their Mechanisms Investigation of Distress Remediation of Distress

22 Flowchart of Process Probable Cause(s) Repair/Rehabilitation Alternatives Patch Sealing /Micro- Milling Surface Level Surface Treatment Over -lay Remove and Replace Recon -struct Structural Section Design and/or Mix Design Cost Analysis Treatment Selection

23 Candidate Rehab & Repair Treatments HMA Patch Reconstruct Sealing/Micro- Milling Surface Leveling Surface Treatment HMA Overlay Remove & Replace (HMA Surface) Pre-Treatments Partial Depth Full Depth Crack Sealing Rout and Seal Saw and Seal* Micro-Milling Cold Milling (Partial Depth) Rut Filler Leveling Course Chip Seal Fog Seal Slurry Seal Microsurfacing Sand Seal Scrub Seal Bonded Wearing Course OGFC Thin Overlay ( 30 mm) CAPM ( 75 mm) Structural Overlay Inlay (PD Mill & Fill) Hot In-Place Recycle Partial Depth CIPR* Full Depth CIPR* Hot Central Plant Recycle Mill & Fill (Full Depth) Full Depth Reclamation Virgin Materials Drainage Improvements Heater Scarify Fabric* Geogrid* SAMI* Distress Type Longitudinal x x x x x x x x x x x x x x Fatigue x x x x x Transverse x Reflective x Block x Edge Rutting x Corrugation Shoving Depression Overlay Bumps Delamination Potholes Patching Raveling Stripping Polished Aggr. Pumping Segregation Checking Bleeding Mat Problems Deterioration Deformation Cracking Distress Category Candidate treatment Marginal treatment. Product selection is critical x Special product or technique required * Requires an overlay or other suitable surface treatment No Caltrans Specification

24 Candidate Rehab & Repair Treatments Partial Depth Full Depth Chip Seal Fog Seal Slurry Seal Microsurfacing Bonded Wearing Course OGFC Thin Overlay ( 30 mm) CAPM ( 75 mm) Structural Overlay Type HMA Patch Surface Treatment HMA Overlay Longitudinal x x x x Fatigue x Transverse x Reflective x Block x Edge Cracking Distress Category Candidate treatment Marginal treatment. Product selection is critical x Special product or technique required

25 Distress Cause(s) Addressed Causes of Pavement Distress Addressed by Rehabilitation and Repair Treatments Low-Strength or Low-Stability Mix Poor Mix Gradation Low Asphalt Content High Asphalt Content Low Air Void Content High Air Void Content Improper Fines Content Tender Mix Segregated Mix Poor Surface Preparation Excess/Insufficient Prime or Tack Improper Crack Sealing Techniques Improper Compaction Techniques Excess Moisture in Mix Low HMA Thickness Low Base/Subbase Thickness Poor Subgrade Compaction Poor Base/Subbase Compaction Poor Base/Subbase Gradation High Asphalt Cement Viscosity Low Asphalt Cement Viscosity Temp. Susceptible Asphalt Cement Rapid Aging Asphalt Cement Moisture Sensitive Mix Poor Aggregate Durability Poor Aggregate Soundness Poor Aggregate Cleanness High Exposure to Moisture Cool/Cold Prevailing Temperatures Hot Prevailing Temperatures Freeze-Thaw Cycling Large Daily Temperature Cycles High Traffic Volume High ESAL Truck Volume Exposure to Studded Tires/Chains Inadequate Pavement Structure Poor Material Selection Poor Drainage Narrow or Non-Existent Shoulder Narrow Lane Width Excessive Horizontal Geometry Candidate Treatments Partial Depth Full Depth Crack Sealing Rout and Seal Saw and Seal* Micro-Milling Cold Milling (P. Depth) Rut Filler Leveling Course Chip Seal x x x Fog Seal Slurry Seal x x x Microsurfacing x x x Sand Seal Scrub Seal Bonded Wearing Course OGFC Thin Overlay ( 30 mm) CAPM ( 75 mm) Structural Overlay Inlay (PD Mill & Fill) Hot In-Place Recycle Partial Depth CIPR* Full-Depth CIPR* Hot Central Plant Rec. Mill & Fill (Full Depth) F.D. Reclamation Virgin Materials Drainage Improvements Heater Scarify Fabric* Geogrid* SAMI* Pre-Treatments Reconstruct Remove and Replace (HMA Surface) HMA Overlay Surface Treatment Surface Leveling Sealing/Micro- Milling HMA Patch Treatment Category Candidate treatment Marginal treatment * Requires an overlay or other suitable surface treatment x Special product or technique required No Caltrans specification

26 Distress Cause(s) Addressed Candidate Treatments Treatment Category Low-Strength or Low-Stability Mix Poor Mix Gradation Low Asphalt Content High Asphalt Content Low Air Void Content High Air Void Content Improper Fines Content Tender Mix Segregated Mix Partial Depth Full Depth Chip Seal Fog Seal Slurry Seal Microsurfacing BWC OGFC Thin Overlay ( 30 mm) CAPM ( 75 mm) HMA Overlay Surface Treatment HMA Patch Structural Overlay Candidate treatment Marginal treatment

27 Use of Treatment Selection Tables Candidate Rehabilitation and Repair Treatments Overall Problem (by Distress Category and Type) Causes of Pavement Addressed by R&R Treatments

28 Development Status Method has been tested on several projects Review process complete Manuals have been finalized and will be produced for statewide distribution One-day training course under development

29 Acknowledgements Terrie Bressette (Caltrans) Rita Leahy (MACTEC) David Peshkin (APTech)

30 Thank You!