De-Bonding of HMA Pavements/Construction Observations
Reviewed by licensed engineers
Checked against its sources by licensed professional engineers on the previous site, where reviewers weren’t recorded by name.
Construction Observations of Some Washington State Projects
The following section presents tack coat application photos and noted overlay construction issues from various WSDOT contracts. These photos and notes are intended to serve as a preliminary collection of data to be used in identifying construction practices and conditions that lead to de-bonding and bottom-up cracking. Information from these specific contracts has been added to this database because WSDOT personal noticed either pickup or questionable applications of tack during construction.
Contract 6772, 6749 and 6688
- The following were done in 2004:
- C#6772, SR 503, MP 13.82 – 29.96, Rock Creek Rd Vic. to Ham Rd Vic. (Some pickup noticed)
- C#6749, SR 12, MP 134.28 – 165.98, Lake Creek to Wildcat Creek
- C#6688, SR 97A, MP 201.57 – 214.20, Wenatchee North Paving
- Contract Locations
Contract #6772
Contract #6749
Contract #6688
Contract 6059, 6098 and 6143
- Projects were completed in 2001:
- C#6059, SR 395, MP 45.36 – 61.24, SR 17 to Adams Co. Line (Light tack on Oxidized surface (Pepper application)).
- C#6098, SR 4, MP 0 – 28.2, Jct. SR 101 to West Valley Creek (Tack truck had issues and needed repeated applications to get coverage).
- C#6143, SR 101, MP 321.7 – 329.07, Jorsted Creek Vic. to Sund Creek (Some pickup was seen)
- Contract Locations
Contract #6059
Contract #6098
Contract #6143
Contract 5816
- Contract 5816, SR 500, MP 8.37-20.37, NE 162nd to SR 14 Vic
- Class A PG 64-22, 0.15' mill and overlay
- Paved in 2000 (6/20 - MP limits that day were 19.1-19.7)
- Project Bid Tab
- Comments: streaked tack coat on milled surface
Contract #5816
Contract 5700
- Contract 5700, SR 101, MP 249-252, Golf Course Road to Morse Creek
- Class A PG 58-22, 0.15' (actual was ~2")
- Paved in 2000 (6/26)
- Project Bid Tab
- Comments: over clean prelevel, thin coat, fairly uniform, CSS-1 w/10% dilution
Contract #5700
Contract 5831
- Contract 5831, SR 2/97, MP 117.15-119.17, Lower Sunnyslope to Easy St
- Class A PG 64-34, 0.15'
- Paved in 2000 (7/12)
- Project Bid Tab
- Comments: CSS-1 w/ ~10% dilution, even distribution, double coverage
Contract #5831
Contract 5677
- Contract 5677, SR 12, MP 118-134, Surrey Creek to Lake Creek Road
- Class 1/2" PG 64-28, 0.15'
- Paved in 2000 (8/1)
- Project Bid Tab
- Comments: tack very light (not even sticky on shoes)
Contract #5677
Contract 5827
- Contract 5827, SR 5, MP 70.9-85.51, SR 508 to Thurston Co Line
- Class A PG 64-22, 0.15'
- Paved in 2000 (8/17)
- Project Bid Tab
- Comments: tack very streaky and not broken
Contract #5827
Contract 5841
- Contract 5841, SR 27, MP 75.66-83.10, Freeman to Vic 32nd Ave
- Class 1/2" PG 64-28, 0.15' mill and overlay
- Paved in 2000 (6/27)
- Project Bid Tab
- Comments: STE-1 used, uniform over milled surface, picking up in wheelpaths (still in valleys of milled surface)
Contract 5807
- Contract 5807, SR 542, MP 21.41-30.92, Hatchery Rd to Nooksack River Bridge
- Class B PG 64-22, 0.12'
- Paved in 2000 (7/19)
- Project Bid Tab
- Comments: very light tack on new prelevel
Contract 5862
- Contract 5862, SR 14, MP 114.06-134.29, Goodnoe Rd to Wood Creek/Alderdale Rd
- Class A PG 64-28, 0.15'
- Paved in 2000 (7/27)
- Project Bid Tab
- Comments: CSS-1 over prelevel, streaky (told application rate was 0.05-0.08)
Contract 5609
- Contract 5609, SR 395, MP 241.73-248.54, Columbia River Bridge to Boyds
- Class B PG 58-34, 0.15' mill and overlay
- Paved in 1999 (date visited was 6/9)
- Project Bid Tab
- Comments: tack coat looked very good
Contract 5701
- Contract 5701, SR 14, MP 11.88-21.77, 6th Ave to Clark Co Line (Contract Location)
- Class A PG 64-22, 0.20' overlay
- Paved in 1999 (9/7)
- Project Bid Tab
- Comments: streaked tack coat
Contract 7060
- Contract 7060, SR 17 (just south of SR 26) - severe delamination during milling.
- Project Bid Tab
- I recall that on I-5 Maytown project, Mel was out there and made them put two coats on a milled surface and it wouldn't break because there was too much tack and it was a relatively cool night. (Jim, do you have pics?)
- Also, I think Jim Weston may have some pictures, but I think on I-90 (contract 6136 or 6151) there was some extreme pick up of the tack in the wheelpaths. Jim will probably have some of the better notes when it comes to tack coat...
De-bonding on the Moanalua Freeway
This is some brief evidence from the State of Hawaii based on cores taken on the Moanalua Freeway.De-bonded pavement cores taken from Moanalua Freeway Ramp 68
Contract #5816
Contract #5816
Teaching this? Figures and worked examples are free to use with credit. Course reading lists
Cite this page
APA
Pavement Interactive. (2026, November 1). De-Bonding of HMA Pavements/Construction observations. HeadLight. Retrieved [the date you read it], from https://pavementinteractive.org/reference-desk/pavement-management/pavement-distresses/de-bonding-of-hma-pavementsconstruction-observations/
ASCE
Pavement Interactive. (2026). “De-Bonding of HMA Pavements/Construction Observations.” HeadLight, <https://pavementinteractive.org/reference-desk/pavement-management/pavement-distresses/de-bonding-of-hma-pavementsconstruction-observations/> ([the date you read it]).
BibTeX
@misc{pavint-de-bonding-of-hma-pavements-construction-observations,
author = {{Pavement Interactive}},
title = {De-Bonding of HMA Pavements/Construction Observations},
year = {2026},
publisher = {HeadLight},
howpublished = {\url{https://pavementinteractive.org/reference-desk/pavement-management/pavement-distresses/de-bonding-of-hma-pavementsconstruction-observations/}},
note = {Accessed [date]}
}