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Estimating Condition-Based Highway Reconstruction Needs. NCHRP 20-24(52) Task 14 (funded by NCHRP 20-7). Estimating Condition-Based Reconstruction NCHRP 20-24(52) Task 14. Questions about models for C & P (HERS & NBIAS) estimating reconstruction for other than traffic or safety
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Estimating Condition-Based Highway ReconstructionNeeds NCHRP 20-24(52) Task 14 (funded by NCHRP 20-7)
Estimating Condition-Based ReconstructionNCHRP 20-24(52) Task 14 • Questions about models for C & P (HERS & NBIAS) estimating reconstruction for other than traffic or safety • 20-7 Quick Turnaround funded Task 14 (4 months) • Survey FHWA, AASHTO & State DOTs • Determine if there is a valid issue • If so, define possible approaches to address
Estimating Condition-Based ReconstructionWorking Group • FHWA • Ross Chrichton, Ian Friedland, Steve Gaj, Darren Timothy, Steve Sissel • AASHTO • Tony Kane, Ken Kobetsky • State DOTs • Caltrans – Michael Johnson • Maryland – Neil Pedersen • New York – Nancy Ross • Consultants • PB - Hal Kassoff, Task Leader • Cambridge – Arlee Reno, Bill Robert, Herb Weinblatt • Alan Pisarski
Estimating Condition-Based ReconstructionDefinitions • Condition-based: physical deterioration (not traffic or safety) • Reconstruction: • Replacement in kind focused on major elements • Roadway: includes full paving section, unsuitable sub grade, failed drainage, etc. • Bridge: includes replacement of > 50% of superstructure or substructure
Estimating Condition-Based ReconstructionInterviewees • FHWA • AASHTO • State DOTs • Arizona • Caltrans • Delaware • Illinois • Louisiana • Maryland • Michigan • Nebraska • New York • Ohio • South Carolina • Tennessee • Vermont • Toll Authority • Pennsylvania Turnpike
Estimating Condition-Based ReconstructionKey Findings • Condition-based Interstate reconstruction needs are not insignificant – most or all of original Interstate not reconstructed for traffic or safety will require condition-based reconstruction in foreseeable future • More prevalent in cold climates • More prevalent in pavements than bridges –examples abound in both • Due to variety of causes – materials, design details, soils, freeze-thaw, excessive traffic, higher axle loadings • Late 1980’s/early 1990’s turning point in durability of constructed pavements and bridges • Would add up to multiple-billions
Estimating Condition-Based ReconstructionRecommendations • Follow-on effort is justified • Two options presented to Working Group • Enhanced Models & Methods • Empirical Adjustment • Enhanced Models & Methods: Multi-year, Multi- millions, Integrated with Models & Methods • Empirical Adjustment: One shot adjustment for Interstates and similar facilities done situationally • Hybrid proposed by working group – Empirical approach but adapted to models and methods
Estimating Condition-Based ReconstructionActions • Complete report • Provide information in larger Interstate report • Decisions by FHWA & AASHTO on how to proceed • Implementing actions through FHWA and NCHRP
Estimating Condition-Based Highway ReconstructionNeeds Questions?