Determination of mechanical properties used in WAY-30 test pavements

Ohio Research Institute for Transportation and the Environment

FHWA/OH-2010/9

Tech Report

Ohio

676688806

Technical report.

Ohio Research Institute for Transportation and the Environment

NTL-HIGHWAY/ROAD TRANSPORTATION-Materials

The US Route 30 bypass of Wooster, Ohio, in Wayne County, “WAY-30”, was constructed to demonstrate two types of

extended service pavements, a long-life Portland cement concrete (PCC) pavement on the eastbound lanes and an asphalt

concrete (AC) perpetual pavement on the westbound lanes. Both pavements are designed to provide 50 years or more of

service with minimal maintenance (e.g. resurfacing). The PCC pavement structure features a thick and extra-wide slab on an

asphalt treated base, while the AC pavement structure features a Superpave surface and a Fatigue Resistant Layer (FRL).

Report FHWA/OH-2008/7 discusses the instrumentation and studies of the response of the pavement under loads. For this

study, samples of all pavement materials, including soils, granular subbase material, PCC mixes, and AC mixes were tested

in the laboratory to determine material parameters. Four asphalt mixes were selected to provide a rut and fatigue resistant

pavement structure, while two mixes of the PCC were used in different sections of the road. The subgrade material was

ODOT type A-4a (AASHTO A-4). The granular subbase material was A-1a with high permeability (1.001 cm/s or 2,838

ft/day). PCC tests included: unit weight, modulus of rupture, static modulus of elasticity, Poisson’s ratio, splitting tensile

strength, compressive strength, maturity, and thermal coefficient of linear expansion. AC test results indicated that the

creation of asphalt-rich bottom by adding additional asphalt binder did work to increase the fatigue resistance by orders of

magnitude. At 70 με, the expected fatigue endurance limit and the designed strain level for the structure, regular 302 mix

showed 20,000 cycles to failure while asphalt-rich 302 mix (Fatigue Resistant Layer) is estimated to have 20 million cycles to

failure. For average climatic and traffic conditions (25°C or 77°F; 10 Hz or 0.1 sec loading time), the overall dynamic moduli

and the resilient moduli of asphalt mixes were higher than the values used in the development of the asphalt perpetual

pavement structure. This will reduce the maximum strain at the bottom of FRL significantly than the designed 70 με. The

rutting test results from asphalt pavement analyzer test and flow numbers obtained from the repeated load test indicated that

all asphalt mixes were rut-resistant. TSRST cracking temperatures of asphalt mixes were lower than the expected pavement

temperatures for the project site determined by LTPPBind software, suggesting the possibility of the low temperature thermal

cracking would be very small.

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US Transportation Collection