IDOT UPDATE

Illinois Association of Aggregate Producers

Eric E. Harm, PEAssistant Chief Engineer

May 18, 2006

New Staffing

• Director of Highways – Milt Sees• Chief of Staff – Clayton Harris III• Chief of Operations – Brice Sheriff• Engineer of Tests – Matt Mueller

SAFETEA-LU

August 10, 2005 $295 B Nationwide $6.18 B Illinois (33% increase) Safety Emphasis

Earmarks

$1.25 B Highway Earmarks Over 300 Earmarks Required Match $315 M Shortfall ± $8 B

Downside

Locals have to match Obligation Ceiling ≈ 85% Funds are not upfront Cost of projects up Mix of projects

High Profile Earmarks New Mississippi River Bridge

$164 M plus $75 M for Missouri O’Hare Western Access

$140 M Prairie Parkway

$207 M River Bridge in Quad-Cities

$12 M plus $48 M for Iowa

Bond Program

?

Recycling

Reclaimed Asphalt Pavement

(RAP)

Let’s Rap on RAP

o Usage is in Chapter 53 BD&E Manual.

o Used successfully for 20 years.o Improvements made over the

years.

What’s Driving The Equation?

Aging systemFew bare pavements to overlay (How

many bare pavements did you drive over to get here?)

Limited new constructionMill and Fill 1:1

Results in excess Newer mixes with polymer limit RAP usage

What’s Driving The Equation?

Problem areasCurrently urbanState wide in future

More RAP’n

o Some agencies are not allowing RAP by showing “0% RAP” on plans.

o SB 120 introduced:• All mixes to use RAP and Rubber

Tires.• Died in committee.

o Need to follow sound usage of resources or it will be legislated to us.

S = I - OStorage = Inflow - Outflow

Piles of RAP = Milling – Reuse

Depends upon: Allowable RAP usage

Recycling Summit – 3 meetings

1. RAP as aggregate.2. Revisit RAP use in HMA.3. Concrete as Aggregate.

RAP as an Aggregate

Increase usage for Non-Quality uses

Look into ways of testing for Quality uses

RAP into HMA

Increase %’s Allow RAP in Polymer Mixes

Recycled Concrete as Aggregate

Change sampling stockpile to 10,000T

Use in HMA?

ASR

Alkali Silica Reactivity

Alkali-Silica Reaction (ASR)

• Alkalies React with Silica

– Alkalies from Cement/Cementitious Materials

– Silica from Aggregate

– Needs Water

– Gel is Formed

– Expands and Cracks The Concrete

ASR on IDOT System

• ASR Confirmed in Districts 3, 4, and 8

– Four bridge parapets

– Two bridge medians

– Two bridge decks

– One pavement

• Constructed Between 1985 and 1997

Cedar Street Bridge Extension (1988)

Cedar Street Bridge Median (1988)

I-255 Pavement (1985-86)

IL 116 over I-39 (1990)

IL 116 over I-39

Optical micrograph showing ASR gel fully filling circular void in center and partially filling circular void to left (width of field is 1.4 mm).

IL 116 over I-39

IL 251 over Mackinaw River (1992)

CTL Report:Cracking Related to ASR IL 29 (1997)

Alkali-Silica Reaction (ASR)

• Why So Long to Find This Problem?– FHWA Training– ASR Takes 5-15 Years to Manifest Itself– Requires Cores (Assumed D-Cracking)– Luck Because Low Alkali Cements Have

Been Used in Highly Reactive Locations

Alkali-Silica Reaction (ASR)

• Current Status– Specification Is In Final Draft Form– Industry Has Provided Numerous

Suggestions For Development– Specification Intent Is To Provide

Reasonable ASR Protection– No Intent To Burden Any One Industry

Quality Tests Quality Tests StreamliningStreamlining

Quality TestsQuality Tests

• Current: Every YearCurrent: Every Year

• New: Every Year or Every Other YearNew: Every Year or Every Other Year

Quality TestsQuality Tests

• Will Not Apply To:Will Not Apply To:– Special ProvisionSpecial Provision– Recycled ProductsRecycled Products

Quality Tests (Coarse)Quality Tests (Coarse)

• Tests Looked At:Tests Looked At:– SoundnessSoundness– AbrasionAbrasion– CountCount

Quality Tests (Fine)Quality Tests (Fine)

• Tests Looked At:Tests Looked At:– SoundnessSoundness– CountCount– Minus (-) #200Minus (-) #200

Quality TestsQuality Tests

• Reviewed 10 Years of Test DataReviewed 10 Years of Test Data

• Entire Ledge Was RatedEntire Ledge Was Rated

• This Year:This Year:– All every year and ½ of every other yearAll every year and ½ of every other year

• Next Year:Next Year:– All every year and other ½ plus any left All every year and other ½ plus any left

from this yearfrom this year

Freeze-thaw TestsFreeze-thaw Tests

• Current FrequencyCurrent Frequency>0.030 – Every Year>0.030 – Every Year

<0.030 – Every Other Year<0.030 – Every Other Year

Freeze-thaw TestsFreeze-thaw Tests

• New FrequencyNew Frequency>0.030 – Every Year>0.030 – Every Year

0.015 – 0.030 – Every Other Year0.015 – 0.030 – Every Other Year

<0.015 – Every Three Years<0.015 – Every Three Years

Quality on Quality on TicketsTickets

Quality on Quality on TicketsTickets

New Approved List

• Alphabetical• P/S #• Quality on Tickets (June 1, 2006)

– Ticket Designation– Material Approval

Quality on Tickets

• Thanks• Being rolled out this year!

Thank You!Thank You!Thank You!Thank You!