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Runway 5-23 at Buffalo Niagara International Airport – A Case Study In Maintaining Pavement Serviceability. Roy D. McQueen, P.E. Roy D. McQueen & Associates, Ltd. www.rdmcqueen.com. 1 st Eastern Region Seminar November 1976. Overview. Basic Principals Case Study. Pavement Life Cycle.
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Runway 5-23 at Buffalo Niagara International Airport – A Case StudyIn Maintaining Pavement Serviceability Roy D. McQueen, P.E. Roy D. McQueen & Associates, Ltd. www.rdmcqueen.com
Overview • Basic Principals • Case Study
Pavement Life Cycle EXCELLENT 40% DROP IN QUALITY GOOD $1.00 FOR RENOVATION HERE FAIR 75% OF LIFE 40% DROP IN QUALITY POOR WILL COST $4.00 TO $5.00 HERE VERY POOR 12% OF LIFE FAILED TIME
Basic References • AC 150/5370-11A, Use of Nondestructive Testing in the Evaluation of Airport Pavements. • AC 150/5380-6A, Pavement Maintenance Manual • AC 150/5320-6E, Airport Pavement Design and Evaluation
Basic Purpose of Pavement Evaluation • Functional Characteristics & Surface Condition • Structural Adequacy Photo Courtesy Dynatest International A/S
Basic Principle • Pavements Fail for Different Reasons: • Load • Environment • Other
Functional vs Structural Analysis • Structural: Ability to support loads • Functional: Condition of Operational Surface
Key to Evaluation Process (1) • Identifying failure mechanism is critical to evaluation process • Necessary to develop appropriate (cost-effective) remediation
Key to Evaluation Process (2) • Differentiation between functional and structural condition is critical • We will focus on each and see how we tie them together
MicroPaver for Functional Analysis
Nondestructive Testing & LEDFAA (FAARFIELD) for Structural Analysis
EvaluationProcess Condition Survey Records Review Develop Testing Plan Report Pavement Testing & Materials Sampling Pavement Evaluation
EvaluationProcess Condition Survey RecordsReview Develop Testing Plan Report Pavement Testing & Materials Sampling Pavement Evaluation
Records Review • Maintenance Records • Computer Database • Corporate Knowledge • Inspection • Aerial Photos • As-built Drawings McQueen & Associates, Ltd.
EvaluationProcess ConditionSurvey Records Review Develop Testing Plan Report Pavement Testing & Materials Sampling Pavement Evaluation
Visual Evaluation • Distinguish between distress categories • Load • Environmental • Other • Calculate PCI
DISTRESSQUANTITY DISTRESSTYPE PCI DISTRESSSEVERITY
Preventive Maintenance Corrective Maint, Rehabilitation, or Reconstruction Normal PCI Decline PCI = 95 100 Critical PCI Pavement Condition Index 0 Time or Traffic McQueen & Associates, Ltd.
Pavement Condition Analysis Previous PCI (1996) Branch Name Runway 12-30 N/A Branch ID RW12 Current PCI (2000) 80 Section ID 01 Predicted PCI (2005) 67 Pavement Section 18” PCC / 6” CTB LCD 06/01/92 DETERIORATION CURVE Runway 12-30 - Section 01 100 90 80 77 80 75 72 70 67 70 60 RW12 - 01 Pavement Condition Index (PCI) 50 Critical 40 30 20 10 0 INSPECTION SUMMARY – EXTRAPOLATED DISTRESS QUANTITIES Previous Current Jan. 2001 Jan. 2002 Jan. 2003 Jan. 2004 Jan. 2005 Inspection Inspection Distress Description Sev Quantity Units Density % Deduct (1996) (2000) 65 JT SEAL DMG H 51. Slabs 50. 12. 65 JT SEAL DMG M 51. Slabs 50. 7. Condition Analysis Data 66 SMALL PATCH H 4.86 Slabs 4.76 6.19 70 SCALING L 19.43 Slabs 19.05 6.75 74 JOINT SPALL L 7.29 Slabs 7.14 2.69 PERCENT OF DEDUCT VALUES BASED ON DISTRESS MECHANISM Load Related Distress (%) Climate/Durability Related Distress (%) Other Related Distress (%) 0 55 45
M&R Policies • Function of Distress Type, Severity, and PCI • Cost-effective maintenance procedures • Examples: • Crack sealing • Patching • Reconstruction, overlay • Mill & fill McQueen & Associates, Ltd.
Maintenance is performed to Increase PCI and Slow Rate of Deterioration Preventive Maintenance PCI Near Critical PCI Pavement Condition Time or Traffic McQueen & Associates, Ltd.
EvaluationProcess Condition Survey Records Review Develop Testing Plan Report Pavement Testing & Materials Sampling Pavement Evaluation
Testing Methods: • Destructive • Test Pits • Semi-Destructive • Coring • Penetrometer • Non-Destructive • Deflectometer • Ground Penetrating Radar
Pavement Coring • Thickness • DCP Access • Materials Sampling • HMA cores • Unbound Base Aggregates • Subgrade Soils Photo Courtesy United States Air Force
Soil Borings • Drill Rig • Split-Spoon Sampling • Standard Penetration Test Photo Courtesy CME, Inc.
Deflection Basin McQueen & Associates, Ltd.
EvaluationProcess Condition Survey Records Review Develop Testing Plan Report Pavement Testing & Materials Sampling PavementEvaluation
Structural Analysis • NDT • Layer & Subgrade Strength • Patterns of Variability in Stiffness • Traffic Study • Evaluation • Expected Structural Life • Pavement Classification Number (PCN) • Allowable Load • Strengthening Options • Overlay • Reconstruction McQueen & Associates, Ltd.
3 McQueen & Associates, Ltd.
EvaluationProcess Condition Survey Records Review Develop Testing Plan Reporting Pavement Testing & Materials Sampling Pavement Evaluation
Primary Evaluation Output • Allowable Load • Structural Life • PCN • Functional Life • Rehabilitation/Strengthening Options McQueen & Associates, Ltd.
LEDFAA Computes Structural Life Directly From Mixed Fleet Traffic
ACN-PCN – COMFAA In ACN Computation mode Enter allowable operating weight coverage will default to 10,000 Read ACN for desired subgrade category
Rehabilitation Method Depends on Whether Problem is Structural or Functional
Runway 5-23 at Buffalo Niagara International Airport A Case Study in Extending Pavement Life
Overview • Airport Layout & Construction Details • Pavement Evaluation/Management Practices • Study Results • Maintenance Activities to Extend Life • Rehabilitation Planning McQueen & Associates, Ltd.
RW 5-23 McQueen & Associates, Ltd.
Construction History • Original Construction 1940’s • 10-in PCC / 7-in Subbase • Extended in Stages through 1964 • 2-in AC Overlay in 1972 • 8-in to 12-in AC Overlay in 1975 McQueen & Associates, Ltd.
Buffalo Climate • 44 Degrees North Latitude on Lake Erie • Cold Winters (0 F) • Many Freeze-Thaw Cycles • Warm Summers (90-95 F) McQueen & Associates, Ltd.
Pavement Evaluation / Management Practices That Were Used • Visual Condition Survey • Nondestructive (HWD) Testing • Pavement Evaluation • Functional – MicroPAVER • Structural – LEDFAA (FAARFIELD) • Program and Budgets McQueen & Associates, Ltd.