O’Hare Modernization Project

Reflective Cracking and Improved

Performance of Grooved Asphalt

September 21st, 2006

Research Overview and Future Tasks

William G. Buttlar, Associate Professor

Imad Al-Qadi, Professor

Hyunwook Kim, Hasan Ozer, Alex Apeagyei, Research Assistants

Outline

• Project Overview (5 min.)

– Reflective Cracking

– Performance of Grooved Asphalt Pavement

• New Tasks Proposed for ’07 (5 min.)

Reflective Cracking Updates

Preliminary Modeling(January – September ‘06)

• Prepare Constitutive Models for ABAQUS Finite Element Program (Creep, Fracture)

• Thermal Cracking Analysis using TCMODEL

Assessment of Existing ORD Pavement

(June-October)

• In Consultation with Mr. David Peshkin, Applied Pavement Technologies

• Review Databases, ORD Pavement Inventory, and PCI Distress Survey Results

• Develop Schematics to Aid in Selection of Priority Pavements for Detailed Study (Example)

Field Sampling and Testing(October-November)

• Field Investigation of Priority Pavements (Coordinated w/ Mr. Peshkin)

• Procurement of 150mm Cores (Away From Gear Loading Areas) for Lab Testing

10-1

100

101

102

103

104

10-2

10-1

100

101

Time (sec)

-30 oC-20 0C-10 0C

Com

plia

nce

(1/G

Pa)

Site-Specific RC Modeling(October-December)

• Finalize Meshes for Priority Pavements (Oct)

• Run Parametric Investigations for Range of Typical Material Properties (Oct-Nov)

• Re-run Parametric Investigations When Lab Results are Available (Nov-Dec)

Performance of Grooved Pvt Update

Literature Review(June – July ‘06)

• Summarized During July Presentation

• Will be Documented in Quarterly Report

• Copies Available Upon Request

Performance Test Development(June-October)

• Feasibility of Adapting Advanced Pavement Analyzer (APA) Assessed

• Logistics and Permission for Testing with of IDOT BMPR’s APA Completed

• Preparation and Testing of Baseline Materials in Development

Field Sampling and Testing(October-December)

• In Conjunction with Mr. David Peshkin, Applied Pavement Technologies and in Parallel with Reflective Cracking Task

• Field Investigation of Priority Pavements

• Procurement of 150mm Cores (away from gear loading areas) and Lab Testing

Proposed Tasksfor ‘07

Proposed Tasks for ‘07

1) Develop Best Practices Guidelines for HMA Overlays at ORD– Goal: Minimize RC severity and subsequent

FOD– PG Binder Selection– Mix Design and Thickness Considerations– HMA Performance Test

Proposed Tasks (cont.)

2) Groove Collapse Modeling

3) Best Practices Guidelines for Grooved Pavement at ORD– Goal: Minimize Deterioration of Grooved

Pavement Surfaces– PG Binder Selection– Mix Design Considerations– Groove Geometry Considerations– Performance Test Protocols

Thank You !!

Methodology

HMAGroove stability

Laboratory Evaluation ModelingData collection

from O’hare

Simulate field collapse mechanism of

grooves

Dynamic loading, surfaceshear stresses, and

micro-structural considerations in FEM

Samples ???

An example for micro-structural considerations• Explicit consideration of surface roughness of interfaces as a micro-

structural property (i.e. saw-tooth model)

• Consider degradation of h in a plasticity model– Degradation due to shear stresses at the pavement surface

– Due to deynamic tire-pavement interaction

PCC tining prior to HMA overlay

h

DE Modeling of Grooved AC Beam

1.5 inch

1/4 inch

1/4 inch

9.5 mm NMAS