1. Shongtao Dai, Ph.D, PE Office of Materials Minnesota Department of Transportation 6/24/08 Kevin Erb University of Wisconsin Extension 9/22/08 Mn/DOT Office of Materials and Road Research Effects of Implements of Husbandry “Farm Equipment” on Pavement Performance Mid 2008 Summary

2. Background n Study initiated by Professional Nutrient Applicators Association of Wisconsin (PNAAW) in consultation with the Wisconsin Towns Association. u Several others with similar interest, including Minnesota County Highway Engineers. Minnesota County Highway Engineers.

3. Background n Determined early on that this is an issue bigger than just Wisconsin u Contacted DOT in 8 states. u Examined existing testing facilities u Chose to partner with Minnesota DOT F Existing research facility (MnROAD) F Similar needs identified

4. Background n Created a multi state Pooled Fund Research Study (2007-2010) u Allowed states and federal government to join project. project. u Iowa, Minnesota, Illinois DOT, Mn Local Road Research Board (LRRB). Research Board (LRRB). u Wisconsin DOT chose not to participate (yet)

5. Background n Industry Partnership u Manure Applicator Associations (WI, MN, IA, OH, PA, MI) PA, MI) u Farm equipment manufacturers

6. Major Objectives n Determine pavement responses to selected agricultural equipment using instrumented pavements. n Compare pavement response to typical 5-axle semi (80,000 lbs).

7. Research Approach n Construct two asphalt test sections that represent typical local roads n Utilize existing concrete pavement test sections at test facility (MnROAD) n Visually assess gravel road

8. What is MnROAD? Very comprehensive pavement research facility. Very comprehensive pavement research facility. u Constructed in 1994 and located about 40 miles NW of the Twin Cities. u Mainline and Low Volume Road. u Originally more than 4500 sensors embedded within 40 sections: F Strain gauges, LVDTs, TDRs, Thermocouples, pressure cells. http://www.dot.state.mn.us/mnroad/index.html

9. Research Approach n Construct two asphalt test sections on MnROAD research facility (A & B) B A

10. n Cell 84 (Thick) u 5.5” HMA with PG58-34 u 9” gravel aggregate base u A-4 subgrade soil (existing subgrade soil). n Cell 83 (Thin)  3.5” HMA with PG58-34 u 8” gravel aggregate base  A-4 subgrade soil (existing subgrade soil). 5.5” HMA 8in. Aggregate base A6 clay subgrade 3.5” HMA 8” Aggregate base A6 clay subgrade 9” Aggregate base

11. Research Approach n Utilize existing concrete pavement test sections at test facility

12. n Existing PCC sections on MnROAD u Cell 32 F 5” PCC F 6” Aggregate base 5” PCC 6” Aggregate base A6 clay subgrade u Cell 54 F 7.5” PCC F 12” Aggregate base 7.5” PCC 12” Aggregate base A6 clay subgrade

13. Research Approach n Build sensors into and below pavement to determine impact of farm equipment compared to an 80,000 lb semi

14. Research Approach n Strain Gauges: measures strain to surface layer (asphalt or concrete) – at bottom of layer, edge of road n Deflection gauges (LVDT): deformation of pavement sections/segments n Contact Pressure (surface): tire-pavement foot print and pressure distribution n Temperature/moisture

15. n Instrumentation of Test Sections u Strain gauges: bottom of HMA (18 per section) u Pressure in base (6 per section) u LVDTs (3 per section) u Base moisture measurement: TDR & ECH20 (8 per section) u Thermocouples (32 in cell 83; 16 in cell 84)

16. Contact pressure gauge (Tekscan)

17. Project Status n Spring – April 2007 u Developed workplan u Select test equipment n Construction done Oct. 2007 n Trial Test – Dec. 2007

18. Project Status n 1 st Spring test – Between Mar 17 & 27, 2008 (Spring thaw period) u Manure trucks, tires, sprayers n 1 st Fall test: Aug 25-Sept 5 (dry fall) u Large tankers, flotation tires n 3 year project u 2 weeks in spring u 2 weeks in fall

19. Yellow are Spring 2008 tested. Pink are Fall 2008 tested equipment

20. S1: 4400 gal S3: 1800 gal S2: 4400 gal

21. T2: 4000 gal T1: 6000 gal T3: 6000 gal

22. 7300 gal 9500 gal 6000 gal

23. Test Configuration n 4 different weight: 0%; 25%; 50%; 80% full* F These 4 percentages allow us to determine the effects of different types of manure and different tank sizes. n 3 different speed: Static; 5 mph; 10 mph n Offset from pavement edge: 0 & 12 inches

24. Test Results n Our goal is to have a wet/dry fall and wet/dry early spring test. n Full data will be available when completed

25. Test Results n Preliminary Data u Tire designs have an impact (brighter color – more pressure on pavement) 6,000 gal tanker @ 80% 80% full0% full

26. Test Results n Preliminary Data u Fall: 7500 gal tanker (0%, 80% full), 80,000 lb semi u Each colored square is 0.7 inches by 0.7 inches 80,000 lb Semi 0% full80% full

27. n Pavement Performance (Rutting)

28. Test Results n Preliminary presentation of 1 st year data: January, 2009 n Full data will be available when completed

29. Thank you