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What is a Resource? • • • • • Any physical or virtual entity of limited availability A new or reserve supply that can be drawn upon when needed Something that one uses to achieve an objective An input to be used in an activity, especially production The ability to deal resourcefully with unusual problems; "a man of resource" Streets and Local Roads Resources Philip Kresge Sr. Director, National Resources National Ready Mixed Concrete Association Streets and Roads Thickness Design Surface smoothness or rideability Thickness Design Longitudinal joint Transverse joint Surface Texture Concrete materials Tiebars Subgrade Subbase Dowel bars (may be optional) Understanding Design Optimization • • Design optimization is the balance of performance features and costs. Design optimization involves adjusting variables to: • • • • Achieve long life (durability) Reduce initial costs Minimize maintenance and rehabilitation costs, and/or Enhance sustainability. Introducing StreetPave • • • • • Software tool primarily for streets and roads Uses mechanistic-empirical modeling for thickness determination (like MEPDG but less complex) Direct comparisons of concrete and asphalt designs Allows life cycle cost analysis (LCCA) to compare “hard costs” (if local cost & performance data available). Approved by VDOT for streets and roads design Global Inputs in StreetPave • • • • Project information Design life Reliability* Failure criteria* • • Terminal serviceability Percent cracked slabs *Should be selected based on policy and experience StreetPave Input Examples First screen of walk-through wizard Life-Cycle Cost Analysis Initial Cost Cost Rehabilitation Costs Maintenance Costs Time Cost Salvage Value Net Present Worth Time Combines all present and future costs (benefits) Where to find StreetPave • Available in two formats • • Full-feature Windows® version in available from ACPA website at www.acpa.org/bookstore Free, limited feature webbased version on ACPA’s website at www.acpa.org/ StreetPave/index.asp What can be done with Concrete an existing Overlays asphalt pavement? Concrete Overlays Historical Review • • • • • Began in late forties and early fifties First used on Airports and Secondary Roads In mid-seventies acceptance grew By late eighties this was normal practice Significant amounts of state and federal highways have been rehabilitated this way Why Concrete Overlays? • • • • • To enhance curb appeal To rehabilitate existing surface To add structural capacity To save money (reduce maintenance) To enhance safety • • Lighting Skid resistance www.cptechcenter.org/publications/overlays/index.htm Ultra-Thin Whitetopping • By Definition • Thicknesses between 2” and 4” • Bonded to underlying surface • Short joint spacing 2’ – 6’ panels • Existing asphalt pavement as base Rte. 30, Lancaster, PA • • • • • • Intersection of Rte. 30 & Oakview Rd. In front of PennDOT County Maintenance Facility Placed Oct. 1995 Existing asphalt pavement less than three years old In excess of 1,500 trucks per day Severe rutting/shoving Copyright ©2010 – NRMCA WWW.NRMCA.ORG Existing asphalt pavement was only 2-3 years old. Severe rutting, in excess of 5 inches, was a continual problem. Smaller vehicles actually “bottomed out” on ridge of asphalt! Copyright ©2010 – NRMCA WWW.NRMCA.ORG High/Early Strength concrete mix used to facilitate opening to traffic in 24 hrs. Copyright ©2010 – NRMCA WWW.NRMCA.ORG Rte. 30, Lancaster, PA • • • Placed Oct. 1995 Over 1,500 trucks per day 8.2+ million trucks in 15 yrs. service Copyright ©2010 – NRMCA WWW.NRMCA.ORG • • Available through the National Concrete Pavement Technology Center www.cptechcenter.org Copyright ©2010 – NRMCA WWW.NRMCA.ORG Other Resources Training presentation available in-house or as online webinar Contact Bob Long at ACPA for details Life-Cycle Costs Executive Overview Life-Cycle Costs Technical Fact Sheet Sustainability Considerations www.nrmca.org www.pavement.com Thank You! Philip Kresge Senior Director, National Resources [email protected]