Virginia Quiet Pavement Implementation Program

The Virginia Department of Transportation (VDOT) / Virginia Center for Transportation Innovation & Research (VCTIR) is now working on a quiet pavement implementation program. The first year of the program will include five demonstration projects with a two-year performance evaluation. The 2011 demonstration projects are all on four-lane, divided high-speed roads with good underlying pavement structures. These projects will help VDOT determine the performance of the new pavements under climate conditions unique to Virginia.
These new types of pavement technologies pursue the goal of reducing highway noise at the source.

These new technologies are:

Asphalt:

• Porous Friction Course: (1”) PFC 9.5 (70-28)
• Porous Friction Course: (1.5”) PFC 12.5 (70-28)
• Asphalt rubber- porous friction course:  (1”) AR-PFC 9.5
• To compare with the control section, stone matrix asphalt: (1.5”) SMA-9.5 (76-22)

Concrete:

• Conventional Diamond Grind
• Innovative Grind Process — Next Generation Concrete Surface
  

  was developed with the aim of reducing tire–pavement noise.  The surface has a combination of diamond grinding and grooving to create a consistent smooth surface.  The grooves create a negative texture that allows a better sound propagation downward as well as outward, thus some reduction of noise is expected.

  Pavement texture as the one used in NGCS, may actually prove beneficial, as it provides “escape paths” for air that lessen the effect of some of the mechanisms like: air-pumping, stick-snap, pipe-resonance.

  Furthermore: negative texture, being flat on top also means that there are not as many bumps that would otherwise punch into the tire, generating noise.

  Next Generation Concrete Surface is a multistep process, which follows the diamond-grinding process with a smoother grind and a longitudinal groove

• To compare with the control section:  Transverse Tine

The global evaluation plan was designed to validate the performance by measuring:

• Tire-pavement and wayside noise
• Skid resistance, ride quality, and splash-spray
• Material and structural stability
• Constructability and cost
• Winter function and maintenance requirements

The Center for Sustainable Transportation Infrastructure (CSTI) at Virginia Tech Transportation Institute (VTTI) is involved in these projects with the responsibility of measuring the Tire-pavement noise at the source using the On-Board Sound Intensity (OBSI) methodology (AASHTO TP76-12).

OBSI: On-Board Sound Intensity measurements provide an efficient, standardized way to measure the noise-reduction benefits of the alternative materials and processes used in these projects, and also to evaluate changes in tire-pavement noise over time. Since tire-pavement interaction is the primary source of traffic noise at highway speeds, measuring tire-pavement noise at its source is the most direct way to quantify the benefits of quieter surfaces.

Asphalt project status – Dec 2011
Leesburg (Asphalt) – Superior Paving
SMA, AR-PFC, PFC: Installation Complete

Williamsburg (Asphalt) – Branscome Inc.
SMA, AR-PFC, PFC: Installation complete

Chester (Asphalt) – Branscome Inc.
SMA, AR-PFC, PFC: Installation complete

Concrete project status – 0ct 2011
Richmond (concrete)
Conventional diamond grind, NGCS: Installation complete

Hampton Roads (concrete)
Conventional diamond grind, NGCS: Installation complete

Planned 2011-2012 activities
Performance evaluation on the five demo projects: OBSI measurements along with other functional conditions (ride quality, skid resistance, splash and spray, etc.)
Accelerated Testing – 2 sections at NCAT Track
2012 Demo Projects:
Two-layer PFC 9.5, SMA 4.75, NGCS.

What “Quiet pavement” is:
General – wearing surface that minimizes tire-pavement noise production and propagation

Baseline Noise VA 2010/11

(click to enlarge)