Project Title: Superload Effect on Pavement Life

Objective/Abstract

The goal of the project is to assess the distresses and damage caused by superloads to Pennsylvania pavements. This information will indicate to PennDOT how pavement design should be modified to account for superloads. A method of quantifying the loss of pavement life due to permitted overloads will be developed from this work.

Equipment/Materials Used

Concrete Fatigue:

• Structural Engineering Laboratory
• Pavement Mechanics and Materials Laboratory
• MTS Fatigue Testing Frame, Load Cell, Actuator
• MTS FlexTest SE
• ASTM Flexural Strength, Compressive Strength, Elastic Modulus Testing
• DA STARNETXE Data Acquisition System
• LVDTs/Strain Gauges

Dowel Looseness:

• Pavement Mechanics and Materials Laboratory
• MTS Fatigue Testing Frame, Load Cell, Actuator
• MTS FlexTest GT
• ASTM Flexural Strength, Compressive Strength, Elastic Modulus Testing
• TE Connectivity GCA Series 250 LVDTs

Principal Investigator(s)

Dr. Julie Vandenbossche

Sponsors and Collaborators

Pennsylvania Department of Transportation

Current Postdoc(s)

Sushobhan Sen

Current Student(s)

Nathanial Buettner, Charles Donnelly, Zachary Brody, Katey Paraskiewicz

Former Personnel

Nicole Souder, Katherine Chmay

Key Findings

• The peak fatigue damage caused by superloads occurs when the concrete slab has a large positive temperature gradient
• Superloads can cause significant fatigue damage on thinner concrete pavements (i.e., 8-inch and 10-inch JPCPs), especially when there is not a concrete shoulder to reduce edge stresses
• Superloads may induce significant contact stresses between the dowel and surrounding concrete, which has the potential to result in accelerated socketing. This socketing reduces the performance of the doweled joint.
• Positive temperature gradients cause curling of the slab, which in turn induces higher bearing stresses.
• Tandem axles have the greatest potential for damage, due to overall vehicle weight and proximity of the axles to the doweled joint.

Potential Impact

By determining the impact of superloads and tandem axles on pavement life, pavement designs can be improved to withstand these superloads. Furthermore, routes for superloads can be adjusted to avoid roads and highways with more vulnerable pavement.

Buzzwords

-structural performance