Nonwoven Geotextile Interlayers in Concrete Pavements Improve Pavement Performance while Reducing Costs:
Improving Pavement in America Pavement engineers are constantly seeking out proven innovative concepts with the potential to improve pavement performance while reducing costs. An example of such a concept is the use of a nonwoven geotextile as an alternative to hot-mix asphalt (HMA) between cementitious layers. Proven by German engineers to be effective, this concept is not common or widespread in the U.S. As part of a recent effort to demonstrate the use of nonwoven geotextile interlayers as concrete pavement interlayers, initial recommendations for materials specifications and better construction practices were developed. Implementation was successful in two recent field trials in Missouri and Oklahoma. Nonwoven geotextile between cementitious layers material:
• Proved to be cost effective—material and installation
• Required minimal training and equipment during construction
• Ease of Construction—Rapid installation, with firsthand observations revealing installation rates exceeding that of paving
• Has the potential to be a viable alternative to more conventional materials as an interlayer in the U.S. pavements
Separation Keeps discontinuities (cracks or joints) in the underlying cementitious layer from reflecting to the surface layer. This requires a material that possesses a degree of compliance that can accommodate the anticipated movements in the base layer.
Drainage Channels away water that infiltrates into the pavement structure at the surface. Water should drain into the interlayer, then along the (cross-) sloped surface to the pavement edge. Because of this, German practice requires that GEOTEXTILE MATERIAL either:
• Terminate next to a drainage layer, or
• Be daylighted (allowing the egress of water)
• Drainage function also requires that the geotextile have enough permeability to allow a minimum flow rate in 3 dimensions
Bedding
• Reduces bearing stresses and the effects of dynamic traffic loads
• Function also requires a geotextile material that has some degree of compliance, but not so much that inadequate support stiffness results
For the nonwoven geotextile webpage, please go to: https://www.thetranstecgroup.com/nonwoven-geotextile-interlayers-concrete-pavements/?utm_medium=email&utm_campaign=January%20Newsletter&utm_content=January%20Newsletter+CID_b4172e3c1ad5eea78f0a4d90eb2c9b12&utm_source=Email%20Campaign%20Monitor&utm_term=Learn%20More
Data Collection: Automatic, Off-Site Concrete Temperature & Maturity Monitoring
Click to go to Command Center AutoCollect Webpage
COMMAND Center has released a new fully autonomous concrete data collection option as part of its concrete temperature and maturity monitoring system named “COMMAND Center AutoCollect”. Teams can:
• Measure concrete temperature history
• Log concrete temperature history
• Calculate maturity
• Evaluate in-place strength while away from the jobsite
By removing the necessity of on-site personnel to collect data, COMMAND Center AutoCollect can save teams:
• Expense
• Labor hours of manually collecting data
Using COMMAND Center maturity monitoring on pavement projects can:
• Prove that in-place concrete has achieved adequate strength sooner than anticipated than by just breaking beams and cylinders
• Roads can be reopened to traffic sooner
For more information, please go to: https://www.commandcenterconcrete.com/autocollect/
TRANSTEC: Engineers Week 2021: Inspiring Words, Thoughts, & Advice from Engineers
National Engineers Week was February 21-27 to celebrate the accomplishments and contributions of engineers, increase understanding of engineering, and spark the interest of younger generations!
In honor of Engineers Week, some of Transtec’s engineers shared their inspirations, thoughts, and advice on being an engineer. The 4 questions asked and answered were:
“Who inspired you to become an engineer?
What do you enjoy most about being an engineer?
What advice do you have for aspiring engineers?
What is your favorite project you’ve worked on and why?”
Click to go to Transtec “Engineers Interview” Webpage
Mengge Yuan, Project Manager
Amanda Gilliland, Project Manager
Mauricio Ruiz, Director of Engineering
Kiran Mohanraj, Project Manager
George Chang, Director of Research
One of the best answers (by Kiran Mohanraj):
“Go for it! You don’t get the kind of satisfaction you get by being an engineer with anything else!”
For all of the interviews, and to learn more about Engineers Week and getting involved, please go to the “2021 Discover Engineers Week” Website: www.discovere.org/our-programs/engineers-week
For the interviews on the Transtec website, please go to: https://www.thetranstecgroup.com/engineers-week-2021-inspiring-words-thoughts-and-advice-from-engineers/?utm_medium=email&utm_campaign=March%20Newsletter&utm_content=March%20Newsletter+CID_1431e0980157569250621f01a704396c&utm_source=Email%20Campaign%20Monitor&utm_term=Keep%20Reading
Research: Pavement Surface Characteristics (PSC), Design, Construction, & Materials Behavior
Click to go to Transtec “PSC Research” Webpage
Several factors affect highway safety including pavement friction, road geometry, traffic conditions, vehicle speed, and environmental conditions.
RESEARCH of PAVEMENT SURFACE CHARACTERISTICS (PSC): Experts in pavement surfaces must understand more than pavements. For over 40 years, Transtec has performed PSC measurements for research study at thousands of pavement locations around the globe; Developed a wide array of research results; Conducted research on noise, texture, smoothness for the Federal Highway Administration (FHWA); state and international agencies in Europe, Asia, and Latin America. Industry leaders are invited to speak about where the industry is headed in the future …
Pavement surface characteristics affect: • roadway safety • comfort • durability • vehicle performance • environmental impact
FRICTION and splash & spray affect safety:
—Safety data shows low friction in conjunction with wet conditions directly correlates to increased number of skid related crashes. Thus,
—Friction is a key factor in highway safety
VIDEO: “FHWA/ATSSA – High Friction Surface Treatments“
The Federal Highway Administration (FHWA) and the American Traffic Safety Services Association (ATSSA) produced a video to help highway agencies and contractors successfully implement high friction surface treatments (HFST) as a crash-reducing safety countermeasure.
For information on FRICTION, please go to: www.thetranstecgroup.com/pavement-surface-characteristics/friction/
SMOOTHNESS directly affects comfort and the public demands good ride quality. Good ride quality comes from understanding of both pavements and vehicle dynamics, and knowledge of the tools and best practices to meet the public’s demands:
—Materials Specifications
—Pavement Grinding Optimization for Cost-effective Corrections
—Slipform Stringline Staking Optimization before Construction
—Many standards related to road profiling and smoothness
—WORKSHOPS on “Best Practices” and Software
For information on SMOOTHNESS, please go to: www.thetranstecgroup.com/pavement-surface-characteristics/smoothness/
TEXTURE is a significant pavement surface characteristic affecting friction, noise, smoothness, and more; and often categorized by wavelengths—length between physically repeating features.
• RoboTex is a unique robotic-based texture-measuring device utilizing a line laser:
—Full 3-D images
—Detailed and intuitive visualization of surface texture
—Full suite of analytical metrics are determined, including mean profile depth (MPD) and spectral metrics
—Texture in longitudinal and transverse directions is evaluated
• Transtec helps with:
—Texture specifications to be met by contractors during construction
—Guidance on texture to optimize safety and noise: concrete surfaces require specifications for curing
—Many ways of finishing concrete pavement: tining, dragging, and grinding, etc.
—Identification & specification of a texture optimized for their particular situation
—Processing guidelines and controls to meet texture, smoothness, and durability requirements
—Texture Testing Standards
—Multiple ways to understand standards
—Analyze and interpret test data
—Testing
• WORKSHOPS on Texture: Basics of surface texture and how texture relates to other surface characteristics including durability, noise, and friction. For information on TEXTURE, please go to: www.thetranstecgroup.com/pavement-surface-characteristics/texture/
NOISE: Experts must also understand pavement acoustics. Tire-pavement noise and solar reflectance (albedo) can be environmental concerns. Traffic noise can be a major environmental concern for many roads and highways. In many cases, the dominant source of traffic noise is tire-pavement noise:
Solutions?
—Build pavements that are quieter
—Noise-abatement strategies like walls or barriers
—Specialized surface texture measurements help understand the root cause of high noise levels from a pavement
—State-of-the-art texture measuring methods and 3-D profiles help diagnose why a pavement surface texture has noise issues
—On-Board Sound Intensity (OBSI) test method to conduct tire-pavement noise measurements across a network of roads
—Create a database or catalog of pavement noise levels for the roads in a region to identify quieter from louder construction methods
—WORKSHOPS for decision-makers and project engineers: Basic introduction about pavement noise. For information on NOISE, please go to: www.thetranstecgroup.com/pavement-surface-characteristics/noise/
For PSC Webpage, please go to: https://www.thetranstecgroup.com/pavement-surface-characteristics/
PAVEMENT DESIGN RESEARCH: Transtec has conducted pavement design research for the Federal Highway Administration since 1992, earning multiple research awards.
PAVEMENT CONSTRUCTION RESEARCH: Transtec conducts extensive research into pavement construction: Intelligent Compaction research and implementation; Intelligent Construction Systems and Technologies implementation; Performance Related Specification development; Real-Time Smoothness (SHRP2); and High Friction Surfaces.
MATERIALS BEHAVIOR RESEARCH: Transtec performs research on pavement construction materials for both private and public clients on many topics including surface characteristics, mix optimization, materials performance, Alkali-Silica Reaction, and Resilient Modulus. For more information, please go to: www.thetranstecgroup.com/services/research
ADDITIONAL TRANSTEC ARTICLES BY ISCP:
JUL 30. 2020: Transtec Group’s Continuous Testing Data Saves Texas Airport from Costly, Major Reconstruction
FEB 26. 2020: TransTech Project Spotlight: 1st PPCP Technology for Bridge Approach Slab Construction—Hwy 60, Iowa
AUG 21. 2019: The Transtec Group Provides Texas Pavement Design—Built to Outlast Design Life—for Longest Highway Loop in U.S.
**GEOTEXTILES:
JUN 20. 2018: PUBLICATION: CP Tech: “…Geotextile vs. Asphalt Interlayers…” AND Transtech Group: “Nonwoven Geotextile Interlayers…” Effective in Germany over 25 years
APR 14. 2017: VIDEO: Video: The Transtec Group Delivers Innovative Pavement Engineering for Winnipeg Transitway
DEC 19. 2016: Canada: The Transtec Group Provides Expert Lifecycle Advisement for Extensive Southwest Calgary Ring Road Project