Concrete Pavement Preservation 2018 TRC Transportation Engineering Conference May 16, 2018 Hot Springs, Arkansas Peter Taylor, PhD., P.E. ptaylor@iastate.edu 1
Outline Service Life Trigger Values Typical Treatments Diamond Grinding Full Depth Repairs Partial Depth Repairs Dowel Bar Retrofit Joint Sealing or Resealing Slab Stabilization/Jacking Cross stitching Summary 2
Service/Investment Maintaining the Service and Investment of a Concrete Pavement by Improved Designs and Cost-Effective PAVEMENT PRESERVATION TECHNIQUES
Life Cycle Thinking Which one was cheaper? To buy To own Resale Maintenance Cost of money 4
Life Cycle Thinking Agency income flat / shrinking Traffic growing Maintenance costs We have to be more efficient just to keep up Do we buy miles, or years? And how do we maintain them? 5
Service Life SHORT TERM PAVEMENT
Service Life LONG TERM PAVEMENT PDR and/or DG
Why Concrete Pavement Preservation Bellefontaine, OH 1925 8
2018 = 125 th Anniversary 9
Asset Management What do we buy? Intended life Ability to resist the loads When do we work on it? Little and often Occasionally Later What sort of work? Rules of thumb Depends on the distress 10
Trigger/Limit Values for Preservation (JPCP) Start Programming Performance Indicator Trigger Value Limit Value Repair Trans. Cracking 1.5-2.5% of slabs cracked 5-15% of slabs cracked Partial, Full, Dowel Bar Repairs Joint Deterioration 2.0-4.0% of joints 15-20% of joints Partial-Depth Repair Joint Faulting 1/8 inch 3/8 1/2 inches* Dowel Bar Retrofit Roughness 90 in/mi 170 in/mi* Diamond Grinding 11
Typical Concrete Preservation Activities Diamond Grinding or Diamond Grooving Full Depth repairs Partial Depth Repairs Dowel Bar Retrofit Joint Sealing or Resealing Slab Stabilization/Jacking Cross stitching 12
Concrete Pavement Preservation Guide 2014 http://www.cptechcenter.org/technical-library/documents/preservation_guide_2nd_ed_508_final.pdf Contains 12 Chapters on Preservation Techniques Introduction Preventive Maintenance and Pavement Preservation Concepts Concrete Pavement Evaluation Slab Stabilization and Slab Jacking Partial-Depth Repairs Full-Depth Repairs Retrofitted Edgedrains Dowel Bar Retrofit, Cross Stitching, and Slot Stitching Diamond Grinding and Grooving Joint Resealing and Crack Sealing Concrete Overlays Strategy Selection 13
Diamond Grinding Remove surface layer using closely spaced blades Makes a smooth, level surface Provides longitudinal texture with desirable friction and low noise Frequently performed with other CPP techniques 14
Diamond Grinding 15
International Roughness Index (IRI) I-10, Katy Freeway, Houston 700,000 sq yds 180 160 140 120 IRI (in/mi) 100 80 60 40 20 0 Left Right Average Left Right Average Left Right Average Left Right Average R1 R2 L1 L2 Pre-NGDG 3-mo Post-NGDG 6-mo Post-NGDG Avg. Post-NGDG 16
OBSI Data (Level by Lane) I-10, Katy Freeway, Houston 700,000 sq yds 17
Full-Depth Repair Key Factors for Success Removal (4 min.) Dowel bar holes (grout vs. epoxy) Proper material selection Proper placement and curing Include as part of Partial-Depth Repair 18
Full Depth Repair 19
Partial-Depth Repair Key Factors for Success Proper selection of candidate projects Proper material selection Identification of repair boundaries Use of joint/crack reformers Achieving good bond Proper placement and curing 20
Partial Depth Repairs 21
Dowel Bar Retrofit Restores load transfer Reduces probability of pumping, faulting, and corner breaks Improves long-term rideability Increases service life 22
Dowel Bar Retrofit 23
Pavement Age vs. DBR Placement 70 60 50 40 30 20 10 0 4107 4235 4340 4616 4706 4902 5009 5122 5144 5193 5270 5686 5712 5827 5926 5968 5981 6025 6334 6473 6520 6529 6757 6883 6916 7084 7293 Age (years) Contract Number Washington DOT PCC Age at DBR DBR In Service (2018) Portion DBR Out of Service) HMA Overlay Reconstructed 24
Slab Stabilization/Jacking Used for Sub Grade Repair Soil collapse Poor Compaction Loss of fines Restore support of slabs Reduce progression of Pumping Joint faulting Corner breaks Fill Void or Level Slab Grout 25
Slab Stabilization/ Jacking 26
Joint and Crack Resealing Minimize infiltration of water and incompressibles Types Hot pour Silicone Compressive seals Reservoir preparation Clean Shape Reduces: Subgrade softening Erosion of fines Spalling 27
Joint Resealing 28
Cross Stitching Used for longitudinal cracks that are in good condition Used to maintain aggregate interlock and provide added reinforcement to crack Strengthen longitudinal cracks Prevent slab migration Maintain aggregate interlock Prevent lane separation Prevent longitudinal joint faulting 29
Cross Stitching 30
Cross Stitching Top View Transverse Joint Cross sectional View See Note B 35 45 Slab Subbase See Note A 24 in. min. 0.75 in. dia. Rebar Epoxy into Place T Cross stitch Holes (Typ.) (Alternate sides of crack) 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. 31
Distress Guide 2018 Surface Defects Surface Delamination Material Related Cracks Transverse & Diagonal Cracking Longitudinal Cracking Corner Cracking Spalling Faulting Joint Warping and Curling Blowups Settlement and Heaves Focus: Identification Causes Prevention Rehabilitation Subgrades & Base Support Conditions CRCP Concrete Overlays, BCOA, BCOC, UBCOA, UBCOC Laboratory & Field Testing 32
Summary This is a challenging time for the transportation industry Innovative, cost-effective solutions are needed to meet these challenges Concrete Pavement Preservation (CPP) can extend pavement life significantly at a competitive cost Many CPP techniques provide sustainable benefits such as increased friction (safety), reduced noise, improved smoothness and long life When building roadways we must begin with the end in mind to ensure durable pavements are constructed 33
Any Questions? www.cptechcenter.org 34