LTPP and Pavement Preservation

Transcription

1 LTPP and Pavement Preservation MWPPP Annual Meeting Kansas City, Missouri Monday September 28, 2015 Gonzalo Rada, Ph.D., P.E. Amec Foster Wheeler E&I, Inc. Principal Investigator

2 Agenda 1. Background 2. Overview of Experiment Approach & Key Considerations 3. Experimental Designs & Project Layouts 2

3 1. Background 3

4 LTPP Mission Increase pavement life by investigation of various designs of pavement structures and rehabilitated pavement structures, using different materials and under different loads, environments, subgrade soil, and maintenance practices Understand how pavements behave and why they behave as they do 4

5 Project Objective Design pavement preservation experiments for the LTPP program Enable LTPP to provide short- and long-term performance data on pavements relative to preservation technology Verify preservation as a viable technology in extending pavement life Document impacts of preservation to enable development and implementation of important products and tools

6 Project Activities Phase I Expert Task Group (ETG) Experiment Designs Materials Sampling & Testing Plans Phase II Performance Monitoring Requirements Construction Requirements for RSCs Other Data Collection Needs Technical Support & Marketing

7 Expert Task Group (ETG) Provide review/feedback throughout development of experiment Anita Bush (Nevada DOT) Colin Franco (Rhode Island DOT) Morgan Kessler (FHWA) David Luhr (Washington State DOT) Magdy Mikhail (Texas DOT) Jim Moulthrop (FP 2 ) Larry Scofield (IGGA) Roger Smith (Texas A&M University)

8 2. Overview of Experiment Approach & Key Considerations 8

9 LTPP Pavement Preservation Experiments SPS-11 AC Pavement Preservation Study SPS-12 PCC Pavement Preservation Study Two experiments; consistent with other LTPP experiments 9

10 Experimental Approach Segregate treatment types and pavement project locations into discrete groups Apply same preservation treatment, at different times, on same pavement structure LTPP focus is on timing/distress propagation rates, while NCAT/MnROAD studies and others focus on treatment comparisons LTPP and NCAT/MnROAD studies complement / supplement each other 10

11 Example SPS-11 Project 6 test sections 1 control (no overlay) and 5 treatment sections: Treatment Test Section 5 (8 years) Treatment Test Section 3 (4 years) Treatment Test Section 1 (0 years) Control Test Section Treatment Test Section 2 (2 years) Treatment Test Section 4 (6 years) Traffic 11

12 Preservation Treatments AC Pavements (SPS-11) Thin HMA overlays (< 1 ) Chip seals Micro Surfacing PCC Pavements (SPS-12) Diamond grinding & DBR Joint sealants Joint penetrating sealers

13 SPS-11: Pavement Types AC overlay of existing AC pavement (AC/AC) SPS-12 : Original jointed plain concrete pavement (JPCP) 13

14 Climate Thresholds: Precipitation of 20 inches/year Freezing Index of 150 F-days/year MERRA data 14

15 Traffic SPS-11 experiment considers both volumes and ESALs, while SPS-12 only considers ESALs Vehicles per Day 1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000 > 9,000 Annual ESALs 100, , , , , , , ,000 > 900,000 LOW HIGH 15

16 Replicates, Repeats & Supplemental Replicates: Two per experimental cell; will depend on funding Repeat: Control test section plus test sections that have not received treatment Supplemental: Highly encouraged; will be supported and monitored by LTPP 16

17 3. Experimental Designs & Project Layouts 17

18 SPS-11 Matrix Wet Dry Freeze No Freeze Freeze No Freeze Moisture Temperature Sub-Experiment / Treatment Thin AC Overlay Chip Seal Micro-Surfacing High Low High Low High Low High Low Traffic 18

19 Typical SPS-11 Layout Treatment Test Section 5 (8 years) Treatment Test Section 3 (4 years) Treatment Test Section 1 (0 years) Control Test Section Treatment Test Section 2 (2 years) Treatment Test Section 4 (6 years) Traffic 19

20 SPS-12 Matrix Wet Dry Freeze No Freeze Freeze No Freeze Moisture Temperature Treatment High Low High Low High Low High Low Diamond Grinding & Dowel Bar Retrofit Traffic Joint Sealant Joint Penetrating Sealers 20

21 Diamond Grinding & DBR Diamond Grinding (5 years) Diamond Grinding & DBR (5 years) Control Test Section Diamond Grinding (0 years) Diamond Grinding & DBR (0 years) Diamond Grinding (10 years) Diamond Grinding & DBR (10 years) Traffic 21

22 Joint Sealant (Cap/Replace Sealant) Sealant 10 Year Intervals Sealant 10 Year Intervals Control: No Sealant Control: Sealant Maintained Control: Sealant kept As-Is Sealant 5 Year Intervals Sealant 5 Year Intervals Traffic 22

23 Penetrating Sealer (Silanes or Siloxanes) Sealer at Year 5; Re- 5 year Intervals Sealer at Year 5; Do Not Re-Apply Control: No Joint Sealant (remove if present); No Sealer Control: Joint Sealant Maintained; No sealer Control: Joint Year 0, but Not Maintained; No sealer Sealer at Year 0; Re- 2 year Intervals Sealer at Year 0; Do Not Re-Apply Traffic 23

24 Typical Test Section 100 ft 50 ft 500 ft 50 ft 100 ft Sampling Area Buffer Area Test Section Buffer Area Sampling Area 24

25 Summary Phase I: Experiment Designs and MS&T Plans will be completed shortly Phase II: has been approved and work will commence shortly Project Schedule: construction and data collection guidelines will be completed by next fall and, once done, will start to recruit projects 25

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