emerging challenges, best practices, and research needs in...
TRANSCRIPT
Emerging Challenges, Best Practices, and Research Needs in Sustainable Winter Road Operations
Xianming Shi, Ph.D., P.E.
Dept. of Civil and Environmental Engineering
Washington State University
August 2, 2015
Pre-Symposium Workshop
1. Life cycle sustainability of WRM operations
2. Benefits & emerging challenges in WRM operations
3. Risks to motor vehicles, infrastructure & environment
4. Societal considerations & performance measures
Outline
2
5. Source control approach to environmental sustainability
6. Reactive approach to environmental sustainability
7. Selection and development of “greener” products
8. A look to the future
Outline (cont’d)
3
1. Life cycle sustainability of WRM operations
Infrastructure Voluntary Evaluation Sustainability Tool: www.sustainablehighways.org, w/ a segment on WM: standard practices, RWIS, SMP, MDSS, etc.
(Los Angeles World Airports, 2010)
4
ISO 14041
ISO 14041
ISO 14042
ISO 14043
ISO 14040
• ISO 14040: 2006, Environmental management – LCA – Principles & Framework
• ISO 14044:2006, EM- LCA – Requirements & Guidelines
(A.A. Butt, 2014, Doctoral Thesis)
LCA framework for pavement decision support at the project level
(Kendall et al., 2008, ASCE Journal of Infrastructure Systems, 14(3), 214-222)
Integrated LCCA/LCA of concrete bridge decks
Interconnected components & S.E. perspective
8
Life cycle of salt and other deicers
www.witnerservices.net
www.ci.bellevue.wa.us
Photo courtesy of M. Mills
www.clf.org
www.modot.org
www.syracuse.com
www.miissoulanews.bigskypress.com
9
Q1. Life cycle sustainability of WRM operations
10
What are the research needs before we can fully account
for the life cycle sustainability of WRM operations?
• Fewer accidents
• Improved mobility
• Reduced travel costs & reduced fuel use
• Sustained economic productivity, continued emergency services, …
11
2a. Benefits in WRM operations
• > 70% roads, 70% population
• Highways: 2.3 $bln/yr + 5 $bln/yr
Statewide study: MnDOT current practices
• (4,600 crashes)= 29% avoided
• $10.9M in travel time savings
• $48.4M in user fuel savings
• Total $227M saved, b/c of 6.2
• Intangible costs & benefits
Ye, Z., Yu, X., Veneziano, D., Shi, X. Evaluation of Winter Maintenance Chemicals and Crashes Using Artificial Neural Network. Transportation Research Record, 2014, Vol. 2440, 43-50.
Ye, Z., Veneziano, D., Shi, X. Estimating Statewide Benefits of Winter Maintenance Operations. Transportation Research Record, 2013, Vol. 2329, 17-23.
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. 12
Highway winter operations in U.S.
Safety evaluation of WRM best practices
• Safety Performance Functions (SPF) to predict average crash frequency for base conditions
• Crash Modification Factors (CMFs) to account for effect of site-specific design features
• Observational before-after study using Empirical Bayes (EB) approach
𝑁𝑒𝑥𝑝𝑒𝑐𝑡𝑒𝑑 = 𝑤 ∗ 𝑁𝑝𝑟𝑒𝑑𝑖𝑐𝑡𝑒𝑑 + 1 −𝑤 ∗ 𝑁𝑜𝑏𝑠𝑒𝑟𝑣𝑒𝑑
𝑤 =1
1 + 𝑘 ∗ ( 𝑁𝑝𝑟𝑒𝑑𝑖𝑐𝑡𝑒𝑑𝑎𝑙𝑙 𝑠𝑡𝑢𝑑𝑦 𝑦𝑒𝑎𝑟𝑠 )
Safety Analysis of FAST
FAST systems contributed to crash reductions of:
o 2% on multilane rural highways
o 16 – 70% on urban interstates
o 31 – 57% on rural interstates
o 19 – 40% on interchange ramps
o Unclear for rural two-lane roads
14 Veneziano, D., Muthumani, A., Shi, X. Safety Effects of Fixed Automated Spray Technology Systems. Transportation Research Record, 2015, in press.
15
Shi, X. Winter Road Maintenance: Best Practices, Emerging Challenges, and Research Needs. Journal of Public Works & Infrastructure 2010, 2(4), 318-326.
Shi, X., Jungwirth, S., Akin, M., Wright, R., Fay, L., Veneziano, D., Zhang, Y., Gong, J., Ye, Z. Evaluating Snow and Ice Control Chemicals for Environmentally Sustainable Highway Maintenance Operations. ASCE Journal of Transportation Engineering, 2014, 140(11), DOI: 10.1061/(ASCE)TE.1943-5436.0000709.
Fay, L., Shi, X. Laboratory Investigation of Performance and Impacts of Snow and Ice Control Chemicals for Winter Road Service. ASCE Journal of Cold Regions Engineering, 2011, 25(3), 89-114. DOI: 10.1061/(ASCE)CR.1943-5495.0000025 (Best Paper, 2011-2012).
16
2b. Emerging challenges in WRM operations
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., Veneziano, D., Xie, N., Gong, J. Use of Chloride-Based Ice Control Products for Sustainable Winter Maintenance: A Balanced Perspective. Cold Regions Science and Technology, 2013, 86, 104-112.
17
Q2. Benefits and emerging challenges in WRM operations
18
How do we balance different priorities and address tradeoffs
in a systematic and defensible framework?
Shi, X., et al. Preserving the Value of Highway Maintenance Equipment against Roadway Deicers: A Case Study and Preliminary Cost Benefit Analysis. Anti-Corrosion Methods and Materials, 2015, in press. Jungwirth, S., et al. Proactive Approaches to Preserving Maintenance Equipment from Roadway Deicers. ASCE Journal of Cold Regions Engineering 2014, DOI: 10.1061/(ASCE)CR.1943-5495.0000085. Li, Y., et al. Corrosion of Chloride Deicers on Highway Maintenance Equipment: Renewed Perspective and Laboratory Investigation. Transportation Research Record, 2013, 2361, 106-113. DOI: 10.3141/2361-13. Shi, X., et al. Exploring the Performance and Corrosivity of Chloride Deicer Solutions: Laboratory Investigation and Quantitative Modeling. Cold Regions Science and Technology, 2013, 86, 36-44. DOI: 10.1016/j.coldregions.2012.10.011. Nazari, H. M., Bergner, D., Shi, X. Best Practices for the Prevention of Corrosion to DOT Equipment: A User’s Manual. Final report for the Minnesota Department of Transportation and the Clear Roads Program, St. Paul, MN. December 2014.
Shi, X., et al. A FESEM/EDX Investigation into How Continuous Deicer Exposure Affects the Chemistry of Portland Cement Concrete. Construction and Building Materials, 2011, 25(2), 957-966. DOI: 10.1016/j.conbuildmat.2010.06.086. Shi, X., et al. Laboratory Investigation and Neural Networks Modeling of Deicer Ingress into Portland Cement Concrete and Its Corrosion Implications. Corrosion Reviews, 2010, 28(3-4), 105-153. Shi, X., et al. Freeze-thaw Damage and Chemical Change of a Portland Cement Concrete In the Presence of Diluted Deicers. Materials and Structures, 2010, 43(7): 933-946. DOI: 10.1617/s11527-009-9557-0. Shi, X., et al. Corrosion of Deicers to Metals in Transportation Infrastructure: Introduction and Recent Developments. Corrosion Reviews, 2009, 27(1-2), 23-52. Shi, X., et al. Exploring the Interactions of Chloride Deicer Solutions with Nanomodified and Micro-modified Asphalt Mixtures Using Artificial Neural Networks. ASCE Journal of Materials in Civil Engineering, 2012, 24(7), 805–815. Pan, T., et al. Laboratory Investigation of Acetate-based Deicing/Anti-icing Agents Deteriorating Airfield Asphalt Concrete. Journal of the Association of Asphalt Paving Technologists (AAPT), 2008, 77, 773-793. 19
3a. Risks to motor vehicles and transportation infrastructure
Based on 250 lb/l-m application rate
(adapted from Winston et al., 2012)
Fay, L., Shi, X., Venner, M., Strecker, E. Toxicological Effects of Chloride-Based Deicers in the Natural Environment. Final Report for the AASHTO Standing Committee on the Environment and National Research Council, Washington, D.C. Feb. 2014.
Jungwirth, S., Shi, X., Strecker, E., Fay, L. Best Management Practices to Mitigate Water Quality Risks and Toxicological Effects of Chloride Based Deicers. ASCE Journal of Cold Regions Engineering, 2015, in review.
Fay, L., Shi, X. Environmental Impacts of Chemicals for Snow and Ice Control: State of the Knowledge. Water, Air & Soil Pollution, 2012, 223, 2751–2770. DOI: 10.1007/s11270-011-1064-6.
(adopted from Granato, 2014)
20
3b. Risks to the natural environment: air, water, soil,
vegetation, wildlife, & human health
Q3. Risks to motor vehicles, infrastructure & environment
21
How do we quantify the risks (and the benefits) with varying
road weather scenarios and site-specific constraints, especially
when they are long-lasting and intangible?
22
4a. Societal considerations
• Traffic crash risk
• User delay costs
• Vehicle operations
• Environmental damage & costs
• Continued emergency services
• Just-in-time delivery services
• Traveler decision / traveler information
• Political and cultural priorities/constraints
• Customer feedback from driving public: to reassess defined performance measures & LOS guidelines
• e.g., surveys and focus groups of Idaho residents
• Generally “Satisfied” with ITD’s winter maintenance and 3 out of 4 respondents indicated they feel “Safe” on Idaho’s highways
• Most respondents had “No Concern” w/ “Plowing” & “Gravel/Sand”
Veneziano, D., Fay, L., Shi, X., Foltz, B., Reyna, M. Highway User Expectations for ITD Winter Maintenance. Final report for the Idaho Transportation Department, Boise, ID. July 2014. 23
Managing user expectation for LOS
Connected vehicles: Concept for WRM
24
• Mobility, accessibility, reliability, safety
• Measured as: time to bare pavement, return to speed limit, friction, visual inspection, winter mobility index
NCHRP 14-34 Guide for Performance
Measures in Snow and Ice Control Operations
25
4b. Performance measures
Iowa DOT salt usage dashboard
• Allocates salt to garages based on weather conditions & policy usage requirements
• Creates a salt budget for each garage
Garage Salt Use Summary Through 4/15/2012 Payperiod 13 & 14
Scale: < 90% 90% - 100% Over 100%
CC GarageAllocation
(Tons)
Salt Used
(Tons)
Salt Target
(Tons)
% Target
Used
% Allocation
Used
D1
551602 Ames 3,057 1,163.4 1,710.4 68.0% 38.1%
551604 Marshalltown 1,871 829.6 1,081.7 76.7% 44.3%
551605 Tama 1,315 717.8 642.5 111.7% 54.6%
551607 Grundy Center 1,714 459.8 689.1 66.7% 26.8%
551608 Iowa Falls 1,796 512.4 820.6 62.5% 28.5%
551609 Williams 2,179 726.3 1,133.7 64.1% 33.3%
551611 Fort Dodge 1,573 558.3 771.6 72.4% 35.5%
551612 Gowrie 840 156.0 449.4 34.7% 18.6%
551613 Jefferson 1,005 459.3 488.1 94.1% 45.7%
551614 Boone 1,263 688.2 573.5 120.0% 54.5%
551802 Malcom 1,185 628.4 674.4 93.2% 53.0%
551803 Grinnell 1,106 488.5 568.9 85.9% 44.2%
551804 Newton 2,370 921.3 1,045.9 88.1% 38.9%
551806 Altoona 1,261 542.6 410.9 132.0% 43.0%
551807 Des Moines North 2,778 972.4 1,012.0 96.1% 35.0%
551808 Grimes 3,750 1,264.8 1,636.0 77.3% 33.7%
551809 Carlisle 1,603 542.7 429.6 126.3% 33.9%
Statewide Salt Use vs. Target
78%
0
100%
200%
Annette Dunn, Iowa DOT
26
Iowa DOT salt usage dashboard (cont’d)
Annette Dunn, Iowa DOT
• Improves performance monitoring, accountability, decision-making
• Cost savings & environmental benefits
27
Q4. Societal considerations and performance measures
28
What are the research needs before we can develop more holistic
and objective performance measures?
• To ensure the implementation of best practices
• To minimize the materials usage (or loss) & associated environmental footprint
• Fay, L., Shi, X., Huang, J. (2013). Strategies to Mitigate the Impacts of Chloride Roadway Deicers on the Natural Environment. Washington, D.C.: National Academies Press. DOI: 10.13140/2.1.1360.2249.
• Fay, L., Akin, M., Shi, X., Veneziano, D. Revised Chapter 8, Winter Operations and Salt, Sand, and Chemical Management. Final report for the National Cooperative Highway Research Program, Washington, D.C. NCHRP 20-07/Task 318. March 2013. 29
5. Source control approach to environmental sustainability
• Salt management plans
• Resource planning (zoning, route optimization,
fleet/crew sizing, location of RWIS, etc.)
• Staff training & workforce development
• Design/operations of road maintenance yards
• Monitoring and record-keeping
• Roadway and pavement design
• Vegetation management
• Innovative snow fences for drift control
• Weather services 30
Source control: proactive strategies/tactics
• Operational strategies
• FAST system
• Pavement innovations
• Maintenance decision support systems
• Pavement sensors & thermal mapping
• Advanced snowplows & spreaders
• Equipment maintenance & calibration
• Material storage & recycling
• … 31
Source control: proactive strategies/tactics (cont’d)
Salt management plans
A statement of policies & objectives
• Identifies: road use, salt vulnerable areas, storage sites & other facilities, snow disposal sites, materials handling, training, …
Documentation
Proposed approaches
Training
oClassroom, CBT, field, post-storm debriefing, simulator, etc.
Management Review
The most effective way
to dispose of snow is
to let it melt where it
accumulates
www.capitalbay.com
32
Roadway design & snow fences for drift control
≥8 ft
Enhance wildlife habitat, control
erosion, improve water quality,
reduce spring-time flooding,
sequester CO2
• Reduce blowing & drifting snow
• Low cost snow storage
• Increased safety
• Reduce need for ice control products
• 25 yr lifespan at $1.40 per ft2
33
Improved weather forecasts
• Reduce the WM costs:
o 11–25% (labor)
o 4-10% (material)
• Improved spatial resolution = greater benefits to
service levels 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. DOI: 10.3141/2107-11.
Strong, C., Shi, X. Benefit-Cost Analysis of Weather Information for Winter Maintenance: A Case Study. Transportation Research Record, 2008, 2055, 119-127. DOI: 10.3141/2055-14.
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. DOI: 10.1080/01441640903414470.
Ye, Z., Strong, C., Fay, L., Shi, X. Cost Benefits of Weather Information for Winter Road Maintenance. Final Report for the Aurora Consortium led by the Iowa DOT, Des Moines, IA. April 2009.
Ye, Z., Shi, X., Wang, S., Ballard, L., Huang, E. A Regional Pilot Weather Information System for Surface Transportation and Incident Management: Concept of Operations. 12th COTA International Conference of Transportation Professionals (CICTP 2012), Beijing, China. August 3-6, 2012.
34
Toolbox approach
Local needs
Rd weather scenarios
Local constraints
Proactive vs. Reactive
o Anti-icing
o Deicing (pre-wet salt, DLA, …)
o Sanding (pre-wet sand, e.g., slurry)
o Mechanical (plowing/blowing)
Operational strategies
Cui, N., Shi, X. Improved User Experience and Scientific Understanding of Anti-icing and Prewetting for Winter Maintenance in North America. Proceedings of the Transportation Research Board 94th Annual Meeting. Jan. 11-15, 2015. Washington, D.C. Paper No. 15-5823. 35
Cost & material savings, benefit/cost: 1.33 to 8.67
Less use of vehicles (and staff overtime)
Lessons learned: time needed to refine forecast and get management on board, continued training & exposure
Tools that integrate road weather forecasts, coded maintenance rules of practice, resource data to provide recommended treatment strategies (FHWA, 2011)
Decision support tools (e.g., MDSS)
36
Ye, Z., Strong, C.K., Shi, X., Conger, S., Huft, D. Benefit-Cost Analysis of Maintenance Decision Support System. Transportation Research Record, 2009, 2107, 95-103.
Ye, Z., Strong, C., Shi, X., Conger, S. Analysis of Maintenance Decision Support System (MDSS) Benefits and Costs. Final Report for the MDSS Pooled Fund led by the South Dakota DOT, Pierre, SD. May 2009.
Maintenance Decision Support System
37
Smart snowplows and sensors
Mobile RWIS: integrated with AVL/GPS to provide improved real-time knowledge of road & environmental conditions throughout a network
• Surface temperature sensors
• Freezing point & ice presence detection sensors
• Salinity sensors
o Linked w/ automatic spreader controls
o Enable educated decisions
oPrevents over-application, saves material & $$$
Ye, Z., Shi, X., Strong, C.K., Larson, R.E. Vehicle-Based Sensor Technologies for Winter Highway Operations. IET Intelligent Transport Systems, 2012, 6(3), 336-345.
GPS/AVL: http://clearroads.org/project/synthesis-on-gpsavl-equipment-used-for-winter-maintenance/
Plug & Play Initiative: http://clearroads.org/project/plug-and-play-initiative/ 38
Q5. Source control approach to environmental sustainability
39
What are the best practices and research needs in source
control?
Chlorides are difficult to remove from the environment!
• Dilution + controlled storage/release (via detention, retention or evaporation ponds; wetlands and shallow marshes)
To mix larger volumes of stormwater to reduce peak [Cl-]
Route the runoff away from sensitive receiving waters
• Infiltration (e.g., via infiltration trenches/basins, vegetated swales and filter strips) vs. groundwater contamination
• Phytoremediation (plant uptake)
• Chloride capture on filter media
6. Reactive approach to environmental sustainability
40
41
Combined use of various BMPs to provide flow control
(Strecker, 2014)
Q6. Reactive approach to environmental sustainability
42
What are the best practices and research needs in reactive
approach?
7. Selection and development of “greener” products
Muthumani, A., Fay, L., Akin, M., Wang, S., Gong, J., Shi, X. Correlating Lab and Field Tests for Evaluation of Deicing and Anti-icing Chemicals: A Review of Potential Approaches. Cold Regions Science and Technology, 2014, 97(1): 21-32. 43
Multi-criteria collaborative decision making
Normalized Data Cost per Lane Mile
Average Performance
Infrastructure/Vehicle Impacts
Environmental Impacts
Composite Index
AF Salt
100
73 59 27 65
BLKFT Salt 86 57 27 55
Firth Salt 83 49 27 53 Boise Salt 86 49 27 54
Regular Salt 73±3 53 43 51±1
AF Slicer 84 50 27 54
Ice Slicer BLKFT 79 56 27 54
Ice Slicer Malad 79 49 27 52
BLKFT Brine
96
26 62 68 63
Pocatello Brine 6 60 68 45
Regular Brine 11±13 60 68 50±10
30% MgCl2 Boise 0 61 82 22 41
Max 100 86 82 68 65
Min 0 2 49 22 41
Shi, X., et al. Evaluating Snow and Ice Control Chemicals for Environmentally Sustainable Highway Maintenance Operations. ASCE Journal of Transportation Engineering, 2014, 140(11), DOI: 10.1061/(ASCE)TE.1943-5436.0000709.
Shi, X., Akin, M. Holistic Approach to Decision Making in the Formulation and Selection of Anti-icing Products. ASCE Journal of Cold Regions Engineering, 2012, 26(3), 103-117.
44
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2.0
2.1
10 20 30 40 50 60
mL
bri
ne
/g d
eic
er
Time (min)
Ice Melt vs. Time 20F
Mix 28
Mix 29
80:20NaCl:Boost
Mix 30
Mix 31
Mix 35
Mix 36
Mix 3
Mix 22
Mix 13Z
45
0
10
20
30
40
50
60
70
80
90
100
NaCl DIWater
Mix 3 Mix 22 Mix 3A Mix 22A Mix 3B Mix 22B Mix 3C 30%MgCl2
23%NaCl
Co
rro
sio
n R
ate
(M
PY
)
Corrosion Rate (MPY)
46
0
10
20
30
40
50
60
70
23%NaCl 30%MgCl2
DI Water Mix 3A Mix 22A Mix 3 Mix 22 Mix 3B Mix 22B Mix 3C
Pe
rce
nt
We
igh
t lo
ss (
%)
Freeze-thaw weight loss of PCC following the SHRP H205.8 test
47
Q7. “Green” anti-icing and deicing products
48
What are the best practices and research needs in “green”
products for snow/ice control?
Muthumani, A., Shi, X. Effectiveness of Liquid Agricultural By-Products and Solid Complex Chlorides for Snow and Ice Control. ASCE Journal of Cold Regions Engineering, 2015.
• Technological and institutional barriers remain!
• Micro-scale road weather forecasting & sensing
• Understanding the ‘dynamic layer’ on the road surface: timing & freq.
• More integrated & automated onboard sensors
• Low-cost, high-reliability FAST system or pavement innovations for ice-prone locations
• A holistic snow/ice control management system
• Ultimate integration of solutions into the WM toolbox: continued investment & efforts in R&D + user-needs driven product strategies
8. A look to the future
49
Q8. A look to the future
50
What are the emerging challenges and solutions in the next five
to ten years?
Q & A for the workshop
51
1. What are the research needs before we can fully account for the life cycle sustainability of WRM operations?
2. How do we balance different priorities and address tradeoffs in a systematic and defensible framework?
3. How do we quantify the risks (and the benefits) with varying road weather scenarios and site-specific constraints, especially when they are long-lasting and intangible?
4. What are the research needs before we can develop more holistic and objective performance measures?
Q & A for the workshop (cont’d)
52
5. What are the best practices and research needs in source control?
6. What are the best practices and research needs in reactive approach?
7. What are the best practices and research needs in “green” products for snow/ice control?
8. What are the emerging challenges and solutions in the next five to ten years?
Questions?
Xianming Shi, PhD, PE
Dept. of Civil & Environmental Engineering
Washington State University
Sloan 101, PO Box 642910
Pullman, WA 99164-2910
Phone: 1-509-335-7088
53
Collaboration?
Additional Slides for Q & A
54
Sustainability practices in the use of traction materials
• Air quality (PM 10)
• Water quality (TMDL/turbidity)
• More materials, lower LOS
• Apply at low speed roads, hills, curves, intersections
• Pre-wetting • Liquid product or hot water • Reduce bounce & scatter • Accelerates breakup of snow/ice and
improve longevity on pavement
• Heating sand
• Cleaning up
55
• Determine baseline & identify trends
• Total length of road
• Winter severity rating
• Number of events
• Material used
• Calibration dates
• Treatment effectiveness
Monitoring & records-keeping
http://clearroads.org/project/calibration-accuracy-of-manual-and-ground-speed-control-spreaders/ 56
An
ti-i
cin
g
• 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
“…prevent the formation or development of
bonded snow & ice by timely applications of a
chemical freezing-point depressant”
Or weaken the bond
57
Prewetting: Slurry Technology
• High volume liquid anti-icer to dry salt (30%:70%) ~ 60-90 gal/ton
• 200 lb/l-mi = ~ 9 gal/l-mi
• Oatmeal consistency, salt grains fully saturated
• Slurry auger & at spinner
• Goes into action quicker, acts immediately, lasts longer on road, out-perform traditional pre-wetting, minimizes bounce & scatter
(Maine DOT 2005)
58
Slurry Technology
• 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
59
Typical Product Application Rates
Product Use Application Rate
Pavement
Temperature
Ranges Reference
Deicing 200 to 800 lbs/l-m 32 to 0°F Levelton Consultants Limited, 2007; Salt Institute, 2007
Anti-icing 20 to 80 gal/l-m 32 to 10°F Levelton Consultants Limited, 2007, Peterson et al. 2010
Pre-wet solid 200 to 800 lbs/l-m 32 to 0°F Levelton Consultants Limited, 2007
Deicing 100 to 400 lbs/l-m Fischel, 2001
Anti-icing 30 to 45 gal/l-m Fischel, 2001
Pre-wetting 10 to 12 gal/l-m Blackburn et al., 2004
Traction sand 500 to 6000 lbs/l-m no limits Levelton Consultants Limited, 2007
Salt-sand mix 500 to 6000 lbs/l-m 32 to 0°F Levelton Consultants Limited, 2007
Pre-wet abrasives 500 to 6000 lbs/l-m no limits Levelton Consultants Limited, 2007
NaCl
MgCl2
and CaCl2
Abrasives
60
Deicing Application Rate Guidelines 24’ of pavement (typical two-lane road)
www.pca.state.mn.us/programs/roadsalt.html
MN Snow and Ice Control Field Handbook for Snowplow Operators
Pavement
Temp. (ºF) and
Trend (↑↓)
Weather
Condition
Maintenance
Actions
Lbs/lane-mile
Salt
Prewetted/
Pretreated With Salt
Brine
Salt Prewetted/
Pretreated With
Other Blends
Dry Salt
Winter Sand
(abrasives)
>30° ↑ Snow Plow, treat
intersections only
80 70 100 not recommended
Frz. Rain Apply chemical 80-160 70-140 100-200
not recommended
30° ↓ Snow Plow & apply
chemical
80-160 70-140 100-200 not recommended
Frz. Rain Apply chemical 150-200 130-180 180-240 not recommended
25 - 30º ↑ Snow Plow & apply
chemical
120-160 100-140 150-200 not recommended
Frz. Rain Apply chemical 150-200 130-180 180-240 not recommended
61
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. Anti-icing for Key Highway Locations: Fixed Automated Spray Technology. Canadian Journal of Civil Engineering, 2013, 40: 11–18. DOI: 10.1139/cjce-2012-0226.
• Muthumani, A., Huang, J., Shi, X. Fixed Automated Spray Technology: Current Practices and Case Study. Proceedings of the Transportation Research Board 94th Annual Meeting. Jan. 11-15, 2015. Washington, D.C. Paper No. 15-1577.
62
• MDSS Benefits (per winter season)
Assume 30% MDSS recommendations were followed.
• Costs per winter season: $332,879
• Benefit-Cost Ratios:
• 2.1 (Same Conditions); 2.6 (Same Salt)
New Hampshire Case Study
Scenarios
Delay
Savings
Crash
Savings
Materials
Savings
Total
Savings
Same Conditions $5,039 $335,052 $354,661 $694,752
Same Salt $72,461 $786,385 $6,624 $865,470
Ye, Z., Strong, C.K., Shi, X., Conger, S., Huft, D. Benefit-Cost Analysis of Maintenance Decision Support System. Transportation Research Record, 2009, 2107, 95-103.
Ye, Z., Strong, C., Shi, X., Conger, S. Analysis of Maintenance Decision Support System (MDSS) Benefits and Costs. Final Report for the MDSS Pooled Fund led by the South Dakota DOT, Pierre, SD. May 2009. 63
Pavement Sensors &Thermal Mapping
• Monitoring, planning, treatment strategies, forecasting
• Invasive & non-invasive
www.vaisala.com
Maine DOT
www.enterpriseflasher.com
www.bangordailynew.com
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Advanced snowplows and spreaders
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Precise Application of Materials
• Tailgate Spreaders & Reverse dumping
• Multipurpose spreaders
• Rear Discharge Spreaders
• Zero velocity spreaders
• Dual spinners
• Modified spinners
• Homemade chutes
Challenges
• Mechanical failure
• Clogging & freezing
• Corrosion
• Frequent calibration
Fay, L., Veneziano, D., Ye, Z., Williams, D., Shi. X. Costs and Benefits of Tools to Maintain Winter Roads: A Renewed Perspective Based on Recent Research. Transportation Research Record, 2010, 2169, 174–186. DOI: 10.3141/2169-19.
Clear Roads Program: Development of a Totally Automated Spreading System. http://clearroads.org/project/development-of-a-totally-automated-spreading-system/.
Clear Roads Program: Comparison of Materials Distribution Systems. http://clearroads.org/project/comparison-of-materials-distribution-systems/. 66
• Monitoring, planning, treatment strategy, prevent over-application
• Colorado DOT
oNon-contract friction measurements
oProvide good short/long-term assessment of product performance
Fric
tio
n M
easu
rem
ents
www.dot.state.oh.us
www.mastrad.com
www.highfrictionroads.com
www.vaisala.com
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A “Supermix” (85% salt brine, 10% De-ice, 5% CaCl2):
anti-icing above 15F @ 40 gln/ln-mi
pre-wetting above 2F @ 10 gln/ton
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