PCCP Preservation Steps to Take to Extend Pavement Life and Performance of Your Concrete Pavements

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1 PCCP Preservation Steps to Take to Extend Pavement Life and Performance of Your Concrete Pavements Larry Scofield, P.E. International Grooving and Grinding Association 1

2 Big Preservation

3 Everybody Wins When it is Funded Roman Road Network Approximately Equal to the US Interstate System-- Cost $3.2 Million per Mile

4 Road Building/Preservation 1993 and Lets Build 100 Miles of Road Funding 2014 Lets Build 67 Miles of Road Arizona Consumption Rate 1995 Lets Drive 39.7 Billion VMT 2014 Lets Drive 59.6 Billion VMT (50%)

5 Increase in Vehicle Miles Traveled and Miles of Roadway ( )

6 Standards in Vehicle Fuel Efficiency Gas Tax

7 It s a New Game In Town International Grooving & Grinding Association 7

8 FHWA Performance Measures Measure IRI (in/mi) Cracking Percent Surface All Pavement s Asphalt Jointed PCCP Population Consideration Population < 1 Million Population > 1 Million Good Fair Poor Good Fair Poor < >170 < >220 No Population Considerations Good Fair Poor < > 10 Assessment Rutting (in) Faulting (in) Cracking Percent Asphalt Jointed PCCP CRCP No Population Considerations Good Fair Poor < > 0.4 No Population Considerations Good Fair Poor < > 0.15 No Population Considerations Good Fair Poor < > 10

9 Why Concrete Pavement Preservation Bellefontaine, Ohio = 125 th Anniversary

10 2016 = 123 rd Anniversary

11 Message Slide Funding and the Transportation System are Critical Components of the National Economy Preservation is Not Only Important it is Absolutely Necessary Times Have Changed International Grooving & Grinding Association 11

12 Concrete Pavement Preservation Guide

13 NHI Web Based Training Modules

14 Typical Concrete Preservation Activities Diamond Grinding or Diamond Grooving Partial Depth or Full Depth Repairs Dowel Bar Retrofit Joint Sealing or Resealing Slab Jacking Longitudinal Crack Stitching

15 Trigger Values for Preservation

16 Grinding Concrete

17 Diamond Grinding Equipment

18 IRI of Concrete Interstate Pavements Kentucky DOT PMS Results IRI Time

19 Full Depth Repair

20 Full-Depth Repairs Workhorse treatment Removal/replacement of concrete pavement at deteriorated joints/cracks Focus on workmanship Dowel bar installation Need for rapid opening times Accelerated materials Precast repairs

21 Full-Depth Repair May also need to: Stabilize Sub Base If distress greater than 1/3 ½ D

22 Full-Depth Repair

23 Dowel Bar Retrofit

24 Dowel-Bar Retrofit Also need to: Reseal Joints

25 Sealing and Resealing Sealant Nozzle Reservoir Backer Rod

26 Slab Stabilization/ Jacking

27 Cross Stitching

28 Cross Stitching Top View Transverse Joint See Note A 24 in. min. Cross-stitch Holes (Typ.) (Alternate sides of crack) Cross-sectional View Slab Subbase See Note B 0.75-in. dia. Rebar Epoxy into Place T Note A: Distance between holes is 24 in. for heavy traffic; 36 in. for light traffic Note B: Determine distance from longitudinal crack to hole based on slab thickness T and drill angle. Slabs less than 12 inches thick require a 35 insertion angle.

29 Partial Depth Patching

30 Good Reference Material International Grooving & Grinding Association 31

31 Partial Depth Repairs (old) Repairs deterioration in the top 1/3 of the slab. Generally located at joints, but can be placed anywhere surface defects occur

32 Repair Layout (old) 2-6 in min. 2-6 in min. Spall Patch 2 in (min.) - t/3 (max.) t

33 Differences in New Manual T/2 CP Tech Center International Grooving & Grinding Association 34

34 Type 1 Repair Layout 2/23/2016 International Grooving & Grinding Association CP Tech Center35

35 Type 2 Repair Distress International Grooving & Grinding Association 36 CP Tech Center

36 Type 2- Repair Layout CP Tech Center International Grooving & Grinding Association 37

37 Type 3 -- Repair CP Tech Center International Grooving & Grinding Association 38

38 Size of Repairs (Old) Minimum length 12 in Minimum width 4 in Go beyond problem by 3-4 in Combine close patches (<2 ft) Repair entire joint if more than 2 patches

39 Repair Materials Concrete Mixes 3/8 Agg, w/c <.44, psi, MnDOT Modified Hydraulic Cement Gypsum Based (1 hr opening, reinforcement) Calcium Aluminate (cold weather, conversion) Polymer Based Resinous Materials Agg added to resins, quick set, Magnesium Phosphate Sensitive to Water, limestone not acceptable

40 Bonding Agents Sand Cement Grouts (2c-1s-1w) Epoxy bonding agents 2/23/2016 International Grooving & Grinding Association 41

41 Construction of Partial- Depth Repairs

42 Finding Unsound Concrete Sounding the pavement: Hammer Steel rod Steel chain DULL SHARP Unsound-Delaminated Solid

43 Sounding the Pavement

44 Concrete Removal Sawing and chipping Carbide milling Transverse Longitudinal

45 Sawing Vertical cut at perimeters Diamond blade Depth to 2 in Overcut slightly

46 Chipping Break to minimum depth of 2 in (1/3 ½) slab thickness maximum) 30 lb maximum hammer 15 lb hammer preferable for control Spade bits preferable to gouge bits Do not expose dowels

47 Removal of Concrete with Jackhammer

48 Milling Machine Requirements: High horsepower rating in milling head width Wheels preferable to tracks Transverse orientation Longitudinal orientation

49 Cold Milling Heads International Grooving & Grinding Association 50 Courtesy CP Tech Center

50 Transverse Orientation

51 Cleaning Sound to check for weak spots before cleaning Chip out with 15 lb hammer if necessary Sandblast bottom and sides Waterblast acceptable alternative: Waiting period to dry

52 Chipping out weak spots

53 Sandblasting

54 Blowing Compressed Air Remove Debris

55 Checking Patch For Cleanliness

56 Joint Insert Separates patch from adjacent concrete Reforms joint reservoir Provides uniform sealing reservoir MUST get below patch material Acceptable materials: Styrofoam Asphalt-impregnated fiberboard Fiberboard

57 Compressible Insert 3 in min. Spall Patch Compressible insert 1 in

58 If Insert Not Used... Point Bearing Popout & Breakage Joint Closure Debonding Expansion Expansion

59 Compressible Joint Insert

60 Cement Grout International Grooving & Grinding Association 61

61 Application of Grout Bonding Agent

62 Placing Patch Material Mix in small quantities Place from wheelbarrows or buggies soon after bonding grout Slightly overfill the patch area Use small spud vibrators (<1 in) Hold at degrees Do not drag!!

63 Finishing & Texturing Match surrounding elevation (grinding) Work tool from center toward edges Texture similar to surrounding pavement Seal saw-cut runouts with grout or liquid epoxy

64 Patch Material Placement International Grooving & Grinding Association 65

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66 Curing High Surface Area 1.5 to 2 Times Normal Application Rate

67 Joint Sealing Resealing joints will help prevent further damage Saw & air blast all joint faces before sealing Seal according to agency specifications (silicone, hot pour, etc.)

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69 Opening to Traffic 3 methods: Specified minimum strength ( psi) Specified minimum time after completing placement (5 or 10 hour patches) Maturity method (mix specific) Strength method preferred Variations in air temperature influence strength development

70 Summary Limit use to top 1/3 (1/2) of slab Avoid point bearing : Use a compressible insert in joints & cracks Cure properly Reseal Joints Quality is Job One

71 Questions