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From page 11... ... 11 C h a p t e r 3 Introduction The major findings from the project were assembled into one application with several resource documents, which collectively serve as guidelines for roadway renewal using existing pavements. Implementation and use of the guidelines will be largely dependent on the ease of use and practicality of the products. Read the entire page →
From page 12... ... 12 asphalt layer is laid upon an already cracked layer. With time, the crack will propagate through the new layer. Read the entire page →
From page 13... ... 13 design life of 5 to 10 years for 4- to 7-in. bonded concrete overlays of asphalt pavements (TxDOT 2011) Read the entire page →
From page 14... ... 14 Table 3.2. Examples of Long-Life JPCP Standards for MnDOT and WSDOT Item Minnesota DOT Washington DOT Design life • 60 years • 50 years Typical structure • Slab thicknesses = 11.5–13.5 in. Read the entire page →
From page 15... ... 15 for low coefficient of thermal expansion, and to provide adequate strength) ; • Dowels and reinforcing (corrosion resistance, sized and located for good load transfer) Read the entire page →
From page 16... ... 16 • HMA over PCC renewal methods 44 HMA over crack and seat JPCPs, 44 HMA over saw, crack, and seat JRCPs, 44 HMA over rubblized JPC pavements, 44 HMA over composite pavements, and 44 HMA over existing CRCPs. HMA Overlay and Existing HMA Pavement If there is no visible distress in the existing HMA pavement other than that in isolated areas, the existing pavement can be directly overlaid as long as it is determined to be structurally sound, level, clean, and capable of bonding to the overlay. Read the entire page →
From page 17... ... 17 in test sections in the United Kingdom (Coley and Carswell 2006) Read the entire page →
From page 18... ... 18 (>50 years) , and their use in the context of long-life pavements, while possible, is still unproven. Read the entire page →
From page 19... ... 19 8 PCC (unreinforced PCC overlays of CRCP) test sections were analyzed. Read the entire page →
From page 20... ... 20 Table 3.4. Summary of Rigid Pavement Renewal Features and Limitations Approach Critical Features Limitations Unbonded PCC overlay over existing PCC • Overlay thickness is critical to performance • Repair locally failed areas • Stable subbase • 1.5-in. Read the entire page →
From page 21... ... 21 Table 3.6. Advantages and Disadvantages of Rigid Pavement Renewal Approaches Rigid Pavement Renewal Approach Advantages Disadvantages Unbonded concrete overlay over PCC • Very good long-term performance with minimal maintenance or rehabilitation • Insensitive to existing pavement condition • Best documented record of projects in place that have achieved long life • Significant surface elevation gain • Placement or cure time may make work-zone management difficult Bonded concrete overlay • Smallest vertical elevation gain • Unlikely to be viable for service lives longer than 35 years Unbonded concrete overlay over HMA • Requires little preparation for existing pavement • Easily accommodates lane addition • Significant surface elevation gain • Placement or cure time may make work-zone management difficult Table 3.7. Read the entire page →
From page 22... ... 22 (JPCP, JRCP, and CRCP) , and composite pavements. Read the entire page →
From page 23... ... 23 Instead, for the flexible alternative, full-depth pulverization or reclamation is recommended along with HMA overlay. The decision process would also recommend an unbonded concrete overlay as a rigid renewal alternative. Read the entire page →
From page 24... ... 24Table 3.9. Feasible Renewal Alternatives for Existing Flexible Pavements Distress Category Specific Distress Description Distress Present? Read the entire page →
From page 25... ... 25 Full-depth fatigue cracking Longitudinal or alligator cracking in wheelpaths Yes Flexible <15% fatigue cracking: patch and repair, moderate thickness AC overlay. Use Tables 3.13–3.15 with 30-ksi base for AC overlay thickness, then subtract existing AC thickness to determine overlay thickness. Read the entire page →
From page 26... ... 26Table 3.10. Feasible Renewal Alternatives for Existing JPCP and JRCP Pavements Distress Category Specific Distress Description Distress Present? Read the entire page →
From page 27... ... 27 Joint faulting -- Yes Flexible option for low faulting (<0.25 in.) Rubblization or crack and seat JPCP with a thick AC overlay. Read the entire page →
From page 28... ... 28 Table 3.11. Feasible Renewal Alternatives for Existing CRCP Pavements Distress Category Specific Distress Description Distress Present? Read the entire page →
From page 29... ... 29 Table 3.12. Feasible Renewal Alternatives for Existing Composite Pavements Distress Category Specific Distress Description Distress Present? Read the entire page →
From page 30... ... 30 Table 3.13. Flexible Pavement Renewal Designs ESALs (millions) Read the entire page →
From page 31... ... 31 approach for pavement renewal with the recommendations provided by the new guidelines. During the visit, the team acquired detailed design information on the project from each agency to be used as a test case. Read the entire page →
From page 32... ... 32 Project Assessment Manual The Project Assessment Manual was prepared to offer agencies a systematic collection of relevant pavement-related data. Furthermore, such data need to be organized to maximize the usefulness in the pavement decision-making process. Read the entire page →
From page 33... ... 33 are discussed. The design and construction for the different long-life approaches are presented in some detail along with quality control and assurance needs. Read the entire page →
From page 34... ... 34 The complete Life-Cycle Cost Analysis manual can be found in this project's guide, Chapter 5. Emerging Pavement Technologies Some PCC and flexible pavement technologies are not yet considered to be long-life renewal options but may become so in the future. Read the entire page →
From page 35... ... 35 of this study. This short treatment simply suggests that technologies exist which should be monitored as they continue to evolve and which may be or become viable components for long-lasting pavement renewal. Read the entire page →
From page 36... ... 36 (e) Section summary (f) Read the entire page →
From page 37... ... 37 in determining the renewal-layer design thickness (described in Step 5) Read the entire page →

From page 11...

... 11 C h a p t e r 3 Introduction The major findings from the project were assembled into one application with several resource documents, which collectively serve as guidelines for roadway renewal using existing pavements. Implementation and use of the guidelines will be largely dependent on the ease of use and practicality of the products.