Pavement Preservation Journal - Spring 2013 - (Page 27)

CENTERS Micro Surfacing Training Offered at Texas Center By Drit Sokoli, Dias Nurgazy and Yetkin Yildirim, P.E. T he Texas Pavement Preservation Center (TPPC) continues its ongoing mission to educate industry practitioners about the most recent developments in pavement technology and knowhow. TPPC’s training courses provide the latest crucial information and advancements in pavement technology to a wide audience of engineers, technicians and policy makers. The Texas Pavement Preservation Center will offer six different training courses in 2013. One of the courses taught by TPPC staff is MNT 705, Guidelines on the Use of Micro Surfacing. This course provides guidelines for planning and designing micro surfacing projects. The application of micro surfacing or slurry seals to existing pavements does not increase the structural capacity of the pavement, but it does help preserve the structural capacity, primarily by reducing the environmental damage that would otherwise develop in the original asphalt concrete pavement from the surface down. There, increased moisture levels will reduce stiffness of most pavement materials. Reduction of moisture infiltration reduces this loss of strength and may allow some strength to be regained during hot, dry periods so it can continue to effectively support traffic loads. This TPPC course is composed of three chapters that cover all the components of micro surfacing. These topics include: TxDOT specifications for micro surfacing, mix design requirements and criteria, different applications and usage of micro surfacing, causes of micro surfacing failures, TxDOT’s use of cape seals, the concept of pavement preservation strategy, guidelines for appropriate selection of roadways for micro Micro surfacing is a durable surface treatment that the Texas Pavement Preservation Center is promoting through educational courses surfacing, guidelines for filling ruts, and guidelines for the use of cape seals. MICRO SURFACING BEST PRACTICES A second course developed by the Texas Pavement Preservation Center, MNT 706, Best Practices of Micro Surfacing. This course builds upon MNT 705 and is intended to provide guidelines for planning, design and construction in micro surfacing projects. More specifically, this course covers the following topics: the components of micro surfacing, how micro surfacing works as a surface treatment, and guidelines for quality assurance and possible problems that may occur. The course is organized in three chapters, starting with an introduction to micro surfacing, which is mostly a review of MNT 705. Chapter two presents the guidelines for quality assurance, while the last chapter gives an overview of the possible problems that could occur in micro surfacing applications. Overall, these two courses will provide attendees with much-needed expertise in the following topics related to micro surfacing: • Selection guidelines. These advise when to use micro surfacing treatments in place of conventional seal coats, in addition to layer thickness guidelines, and when not to use micro surfacing as a surface treatment. • Opening to traffic guidelines. In most of the cases, micro surfacing can handle rolling traffic in less than one hour after placement without damaging the pavement, but stopand-go traffic—especially heavy vehicles in cool, moist or very hot weather—may require additional curing time. • Quality assurance guidelines. Micro surfacing, as a material, appears to be at odds with many of the techniques that TxDOT inspectors have developed over the years to ensure that quality hot-mixed asphalt concrete pavements are constructed. For example, micro surfacing requires that the surface be pre-wet, whereas normal hot-mix asphalt application requires a dry surface. Training is needed to give direction for the proper checks and tests that take place during the application of micro surfacing and slurry seals in order to ensure that a quality product is provided by the contractor. • Possible problems, prevention and correction. Micro surfacings and slurry seals are relatively new maintenance techniques, and even TxDOT inspectors may not be familiar with the potential problems that can occur on site. Training is needed to provide inspectors and construction personnel with the required information to prevent and/or correct problems which can occur during micro surfacing applications. Yildirim is director, Texas Pavement Preservation Center Spring 2013 pavement preservation journal 27

Table of Contents for the Digital Edition of Pavement Preservation Journal - Spring 2013

President’s Message
MAP-21: Pathway to Preservation at the Federal Funding Level
Cold-in-Place Recycling, Fiber Membrane and Seal Preserves Desert Highway
NCPP: New Online Tool Helps Measure Road Network Health
NCAT UPDATE: Axle Loads, Mileage Begin to Accumulate on NCAT Tests
NEPPP: Ribbon Cuttings Shine Spotlight on New Hampshire Pavement Preservation
TPPC: Micro Surfacing Training Offered at Texas Center
MnROAD Studies Pavement Preservation
Enlist News Media in Battle for Pavement Preservation
HIR Solves Cost Challenge to Runway Reconstruction
Shale Gas Boom Drives Town’s Bridge Renovation
Optimum Time for Slurry Seal Depends on Original Build Dat
Index of Advertisers

Pavement Preservation Journal - Spring 2013