AD/AB - LCCA2nd Session

Wednesday, January 29th

AD/AB - LCCA(Alternate Design – Alternate Bid/Life Cycle Cost Analysis)

• Changes in Pennsylvania• Issues under discussion

SEP-14 FOR AD/AB

2009 – 20119/10 went asphaltOnly 2/10 had concrete bids

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 LCCAJune 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!