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AD/AB - LCCA 2 nd Session. Wednesday, January 29th. AD/AB - LCCA (Alternate Design – Alternate Bid/Life Cycle Cost Analysis) Changes in Pennsylvania Issues under discussion. 2009 – 2011 9/10 went asphalt Only 2/10 had concrete bids. SEP-14 FOR AD/AB. FHWA AB Guidelines
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AD/AB - LCCA 2nd Session Wednesday, January 29th
AD/AB - LCCA • (Alternate Design – Alternate Bid/Life Cycle Cost Analysis) • Changes in Pennsylvania • Issues under discussion
2009 – 2011 • 9/10 went asphalt • Only 2/10 had concrete bids SEP-14 FOR AD/AB
FHWA AB Guidelines • “Do not encourage” “Since DOTs want to use” • Equivalent designs and performance over the same period • No longer experimental
Alternate Bidding • A + “C”, where: A is the bid for initial construction C is the cost of future maintenance
“C” = summing the PW of future maintenance and M&PT (50 year evaluation period)
DOT/FHWA/Industry Committee Formed Spring 2012
GAO Report on LCCA June 2013 • Evaluate states’ LCCAs • Required by MAP-21 • Surveyed 13 selected states • 8/13 included User Delay in LCCA
Evaluation period ranged from 25 to 55 years • States do comply and variability is justified
“Pavement Policy Manual” Publication 242 • New Chapter 3 • “Pavement Type Determination”
When is AD/AB and LCCA applicable? • Construction, reconstruction or • major rehabilitation • 30,000 sq yds or greater of main line • Pavement design and LCCA
What are some exclusions to having to bid pavement alternates? • Difference of 10% or more without UDC • Difference of 20% or more with UDC. . .
Exclusions (continued) • Engineering judgement • Adjacent pavement types • Subgrade condition • Right-of-way constraints
How are “User Delay” costs considered in LCCA process? • UDC will not be included in C-factor • Calculated for initial construction and • each maintenance activity and • brought to PW • If 20% or greater difference • including UDC, exception to AD/AB
What discount rate should be used in LCCA? • 6, 4, 2%? • 5 year rolling average of OMB Circular 94 (published annually)
Should “Price Adjustment Clauses” be used with alternate bidding? • PACs have been used in PA for decades • Proven benefit to owner and industry…
PACs (continued) • Equates pavement types on a risk basis • Change threshold for PACs from 10% to 20% and greater
How are “Residual Life” and “Salvage Value” considered in LCCA? • Currently only residual life for concrete (5 years) • Proposal to eliminate residual life and make treatment cycles come out equal to the evaluation period
How are maintenance treatment and cycles established? • Historical performance data • State preferences…
Established (continued) • Proposed AC goes from 10 years to 15 years • Concrete goes from 1 grind and 2 overlays to 2 grinds and 1 overlay
What about production rates and unit cost inputs? • PennDOT and industry teams for both asphalt and concrete updated this data
Give the engineers/administrators latitude to make good decisions! LCCA just a tool!
Give credence to relative performance and motorists’ preference!