Loading in 2 Seconds...
Loading in 2 Seconds...
SESSION: DEICER MANAGEMENT SOLUTIONS June 18, 2014, 2:30pm. Track B OVERVIEW OF CHAPTER 8, WINTER OPERATIONS AND SALT, SAND, AND CHEMICAL MANAGEMENT OF THE NCHRP REPORT 25-25(04) Xianming Shi, Montana State University EVALUATION OF SALT-RICH BIOCHAR AS A ROADWAY DE-ICING AGENT IN SUPPORT OF THE RECYCLING OF APPLIED ROAD SALTS THROUGH PHYTOREMEDIATION AND BIO-FUEL PRODUCTION Andy Alden, Virginia Tech Transportation Institute (VTTI) SALT MANAGEMENT RESEARCH IN VIRGINIA Jimmy White, Virginia Center for Transportation Innovation & Research
SESSION: DEICER MANAGEMENT SOLUTIONS Overview of Chapter 8, Winter Operations and Salt, Sand, and Chemical Management of the NCHRP Report 25-25(04 Xianming Shi, Montana State University The Revised Chapter 8 presents information on recommended practices and strategic planning for reduced salt usage, highlights innovative DOT practices and programs that achieved reductions or improved environmental outcomes. Specific topics covered include: • Basic information on the most commonly used snow and ice control materials, their impacts on the environment, and public concerns on the use of these products. • Strategic planning and stewardship practices that can be used to reduce snow and ice material usage, such as anti-icing, utilizing available pavement and weather information, etc. • Precision application methods and material distribution systems. • The importance of record keeping and monitoring, management at winter operations facilities, and appropriate training of winter maintenance personnel. This work also provides research recommendations to address knowledge gaps or areas with limited or little research on the topics discussed in Revised Chapter 8. Research Interests1. Durability of civil infrastructure: understanding, preventing or mitigating the impact of service environment on metals, concrete, asphalt and structures (e.g., corrosion monitoring system, high performance coatings, preservation and maintenance techniques for pavements, and rehabilitation techniques for bridge decks).2. Environmental sustainability: with a focus on the use of nanotechnology, green technology, and beneficial microorganisms for: environmentally friendly concrete, advanced cementitious materials, eco-friendly asphalt, green buildings, and environmental preservation3. Sustainable transportation systems engineering, especially products, technologies, and systems to facilitate environmentally responsible best practices in road weather management, snow and ice control, dust suppression, and other maintenance activities.4. New energy technologies: microbial fuel cells, energy harvesting, advanced functional materials, etc.
Minimizing the Environmental Footprint of Winter Highway Operations Xianming Shi, PhD, PE, Research Professor A Presentation at 2014 TRB Committee ADC60 Sustainable & Resilient Infrastructure Workshop New York City, June 18, 2014
Revised Chapter 8,Winter Operations and Salt, Sand & Chemical Management, of the Final Report NCHRP 25-25(04) Environmental Stewardship Practices, Procedures, and Policies for Highway Construction and Maintenance My coauthors: Laura Fay, Laura Fay, Michelle Akin, David Veneziano
Supplemented by:NCHRP Synthesis 449,Strategies to Mitigate the Impacts of Chloride Roadway Deicers on the Natural Environment My coauthors: Laura Fay, Jiang Huang
Outline • Impacts of Winter Highway Operations • Reducing Sand Usage • Strategic Planning to Reduce Salt Usage • Proactive Stewardship Practices • Precision Application • Monitoring & Keeping Records • WM Facility Management • Training • Concluding Remarks Photo courtesy of GNP.
1. Benefits of Winter Highway Operations • Fewer accidents, improved mobility, reduced travel costs, reduced fuel use • Sustained economic productivity, continued emergency services, …
1a. WM in the U.S. • > 70% roads, 70% population • Hwys: 2.3 $bln/yr + 5 $bln/yr • MnDOT Case Study: • (4,600 crashes)= 29% ↓ • $10.9M in travel time savings • $48.4M in user fuel savings • Total $227M saved, b/c of 6.2 • Intangible benefits • Ye, Z., Veneziano, D., Shi, X. Transportation Research Record, 2013, 2329: 17. • Ye, Z., ..., Shi, X. Transportation Research Record, 2014, in press. • Fay, L., Veneziano, D., Ye, Z., Williams, D., Shi. X. Transportation Research Record 2010, 2169: 174.
1b. Emerging Challenges Shi, X.Journal of Public Works & Infrastructure 2010, 2(4): 318.
1c. Impacts of Salt & Other Deicers www.modot.org Photo courtesy of M. Mills www.witnerservices.net www.miissoulanews.bigskypress.com www.clf.org www.ci.bellevue.wa.us www.syracuse.com
1d. Impacts of Salt & Other Deicers (cont’d) Sustainability = economic growth + social progress + ecological balance • Fay, L., Shi, X. ASCE Journal of Cold Regions Engineering 2011, 25(3): 89. • Shi, X., et al. Cold Regions Sci. Eng. 2013, 86: 36; Corrosion Reviews 2010, 28(3-4): 105. Corrosion Reviews 2009, 27(1-2): 23. Materials & Structures 2010, 43(7): 933. Construction & Building Materials 2011, 25(2): 957.ASCE Journal of Materials in Civil Engineering, 2012, 24(7): 805. • Pan, T., He, X., Shi, X. Journal of theAssociation of Asphalt Paving Technologists (AAPT) 2008, 77: 773. • Fay, L., Shi, X. Water, Air & Soil Pollution, 2012, 223: 2751.
2. Reducing Sand Usage & Managing Traction Materials • More materials, lower LOS • Pre-wetting • Liquid product • Hot water • Heating sand • Using other materials • Reduce bounce/scatter • Apply in appropriate locations • Low speed roads, hills, curves, intersections
3a. Salt Management Plans • A statement of policies & objectives • Identifies: road use, salt vulnerable areas, storage sites, snow disposal sites, training, … • Documentation • Proposed approaches • Training & Management Review
3b. Iowa DOT Salt Model • Allocates salt to garages based on weather conditions & policy usage requirements. • Creates a salt budget for each garage Annette Dunn Iowa DOT
3c. Salt Matrix & Pre-set Spreader Application Rates Kentucky Department of Highways • Goal: Reduce application rates while maintaining same LOS • Considers: pavement temp., heating/cooling trends, road condition at time of service, available maintenance strategies • Provides: recommended application rates for liquid and solid for initial & subsequent treatments on reference sheets • 4 storm scenarios (light, moderate, & heavy snow, freezing rain) • Drivers use their judgment to make decisions
4. Proactive Stewardship Practices for Reducing Salt, Sand & Chemical Usage
“…prevent the formation or development of bonded snow & ice by timely applications of a chemical freezing-point depressant” (vs. DLA) 4a. Anti-icing • LOS, product, abrasives & plowing • 20 – 65 gal/l-m • Cost savings + mobility & safety • reducing impacts to the environment, infrastructure, vehicles • Limitations: • Cold temps, rain/sleet, blowing snow, air temp above freezing & rising, high humidity
4b. RWIS Real-time road condition information • Used to time treatments & determine which treatments to use • Benefits: • LOS • Cost savings • Aid in maintenance response • Efficiency • Benefit/cost ratio : 1.4 to 11
www.vaisala.com 4c. Pavement Sensors & Thermal Mapping Maine DOT • Monitoring, planning, treatment strategies, forecasting • Invasive and non-invasive www.enterpriseflasher.com www.bangordailynew.com www.cbc.ca
www.vaisala.com 4d. Friction Measurements • Monitoring, planning, treatment strategy, prevent over-application • Colorado DOT • Non-contract friction measurements • Provide good short/long-term assessment of product performance www.mastrad.com www.highfrictionroads.com www.dot.state.oh.us
4e. Residual Chemical Measurement Salinity sensors have been used to make educated decisions about reapplication (Ye et al., 2012). • Monitor road surface product concentration • On-vehicle, embedded, or non-contact • Accurate/recalibrated application rates • Link measurements with automatic spreader controls • Benefits: • Prevents over-application, saves material & $$$
4f. Road Weather Management Decision Support Tools that integrate road weather forecasts, coded maintenance rules of practice, resource data to provide recommended treatment strategies (FHWA 2011) • Cost & material savings, benefit/cost: 1.33 to 8.67, less use of vehicles • Lessons learned: time needed to refine forecast & get management on board, continued training & exposure
4h. Improved Weather Forecasts Strong, C.K., Ye, Z., Shi, X. Safety Effects of Winter Weather: The State of Knowledge and Remaining Challenges. Transport Reviews 2010, 30(6), 677-699. Ye, Z., Shi, X., Strong, C.K., Greenfield, T. H. Evaluation of the Effects of Weather Information on Winter Maintenance Costs. Transportation Research Record 2009, 2107, 104-110. Strong, C., Shi, X. Benefit-Cost Analysis of Weather Information for Winter Maintenance: A Case Study. Transportation Research Record 2008, 2055, 119-127.
4i. Drift Control & Snow Fences • Reduce blowing & drifting snow • Low cost snow storage • Increased safety • Reduce need for ice control product • 25 yr lifespan at $1.40 per ft2 Wildlife habitat, control erosion, improve water quality, reduce spring-time flooding, sequester carbon ≥8 ft
5. Precision Application to Manage & Reduce Chemical Applications • Benefits • Improved material placement • Return on investment • Reduced chemical usage • Improved environmental stewardship • Costs • Equipment • Training • Calibration
5a. Material Distribution Systems Challenges • Mechanical failure • Clogging & freezing • Corrosion • Frequent calibration • Tailgate Spreaders & Reverse dumping • Multipurpose spreaders • Rear Discharge Spreaders • Zero velocity spreaders • Dual spinners • Spinner • Modified spinners • Homemade chutes
5b. FAST Systems • Reduced mobile operations • Reduced crash frequency &delay • Less material required • Challenges • Activation frequency • System maintenance & training • Appropriate only at a highly localized level, as a supplement to mobile operations • Installation should be site specific • Ye, Z., Wu, J., El Ferradi, N., Shi, X. Canadian Journal of Civil Engineering, 2013, 40: 11–18.
5c. Calibration • Is a must • Train how to calibrate & keep records • When to calibrate: • when first acquired • points throughout a season • whenever a new material is used • after repairs • if there appears to be discrepancy in material usage
6. Monitoring & Keeping Records • Determine your baseline • Use collected data to find trends • Consider tracking: • Total length of road • Winter severity rating • Number of events • Material used • Calibration dates • Treatment effectiveness
7. WM Facility Management7a. Material Storage • All products should be stored in a manner to minimize any loss of product www.syracuse.com
7b. Management of Snow Disposal Sites • If moving snow to a melting location: • Minimize impacts (dust, litter, etc.) • Manage meltwater to comply with local water quality regulations • Routinely monitoring of site capacity, soil & water The most effective way to dispose of snow is to let it melt where it accumulates.
8. Training for Salt Management & WM Operations • Assess the needs of your staff • Consider who is being trained & how to best convey that info • Design training based on learning goals • Training methods: • Classroom, field, post-storm debriefing, simulator, etc.
8a. Training Continued… • Have experienced staff conduct the training • Evaluate your training program • Assess how much information was learned • Common training methods: • Annual operator training, Snow University, Snow & Ice Rodeo, Computer Based Training (CBT) www.triblocal.com www.capitalbay.com
9. Concluding Remarks WHAT: deliver the right type & amount of materials in the right location at the right time WHY: effectiveness & efficiency of winter operations material usage, $$$, environmental footprint HOW to balance LOS vs. sustainability: best practice in technology & management domains Shi, X., et al. Cold Regions Science and Technology, 2013, 86: 104.
Acknowledgements • Gabriel Guevara • Leland Smithson • Frank Lisle • Amir Hanna • Annette Dunn • Monty Mills • Michael Williams • Brian Burn • AASHTO Standing Committee on Highways • Caleb Dobbins • William Hoffman • Steve Lund • Debra Nelson • Wilfrid Nixon • Max Perchanok
Contact Info Xianming Shi, Ph.D., P.E., Research Professor Manager, Winter Maintenance & Effects Program Western Transportation Institute, PO Box 174250, Bozeman, MT 59717-4250 Xianming_s@coe.montana.edu Web: www.coe.montana.edu/me/faculty/Shi/ http://ine.uaf.edu/cesticc/ 406-994-6486 (Phone) 406-994-1697 (Fax)
Weather Forecasts and Information Services • Research has shown that winter maintenance costs decrease as the use of weather information increases (Ye et al., 2009). • Accurate and timely forecasts have been shown to save 11–25% (labor) and 4-10% (material), but using a bad forecast can cost you (Shi et al., 2007) • Improved spatial resolution will provide greater expected benefits to service levels (Fu et al., 2009).
Electronic Spreader Controls • Pre-set or on-demand application rates • Use electronic ground speed controls to provide consistent application rates. • Can be linked with sensors (e.g. friction, AVL, GPS) • Modern units can record information about • Application rate, gate position, run time, blast information, avg. spread width/symmetry.
Rearward Casting Spreaders(Ground-Speed and Zero-Velocity Spreaders) • Material is discharged rearward at the same speed as the spreading vehicle is traveling forward. • Keeps more material on the road where it was placed. • Application speeds should not exceed 35 mph, higher speeds reduce application accuracy.
Pre-Wetting Solid Material • Adding liquid to products or abrasives at stockpile or at the spreader • Benefits • Eases product management and distribution • Accelerates breakup of snow/ice and enhances melting • Minimizes bounce and scatter, improves performance • Increases longevity on road = less frequent applications
Case Study: Slurry Technology • High volume liquid anti-icer to dry salt (30%:70%) ~ 60-90 gal/ton • 200 lb/l-m = ~ 9 gal • Oatmeal consistency, salt grains fully saturated • Slurry auger and at spinner (Maine DOT 2005)
Slurry Technology Contd. • Lesson Learned • ¾ in salt allowed but smaller grains work better. • Start with a heavier application, followed by smaller • Some equipment has worked better than others • Pumps, on board crushers, overall equipment design/functionality • Material and cost savings (Maine DOT 2005) • Anecdotal comments: • Goes into action quicker, acts immediately, lasts longer on road, out-perform traditional pre-wetting methods, minimizes bounce and scatter.
Performance Measures • Environmental Performance Measures • Maintain or improve ecosystem, habitat, biodiversity, water quality, wetlands, air quality. • Example: water quality monitoring • Data collection: hydrologic, biologic, atmospheric, etc. • Resources • Environmental Guidebook (FHWA), Environmental Review Toolkit (FHWA), Center for Environmental Excellence (AASHTO), Eco-Logical, FHWA INVEST Sustainable Highways Self Evaluation Tool
Performance Measures • Winter Operations Performance Measures • Mobility, reliability, accessibility, safety • Example: time to bare lane • Measured as: return to speed, friction, visual inspection, etc. www.pbase.com
A Look to the Future • Technological & institutional barriers remain • Micro-scale road wx forecasting and sensing • ‘dynamic layer’ on the road surface: timing & freq. • More integrated & automated onboard sensors + VII • Performance measures + systematic approach to decision making in materials selection • Ultimate integration into the WM toolbox: continued investment & efforts in R&D + user-needs driven product strategies