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2/17/16
2016 Nebraska Asphalt Paving Conference 1
NDOR Update to Bridge Membrane and Asphalt Overlay
§ Asphalt Overlays in 70s
o Used Water Proof Membrane
§ Asphalt Overlays in 70s
o Began as an End-‐Of-‐Life Strategy o Approximately 50 Bridges had Water Proof Membrane and Asphalt Overlay installed (‘73 – ’77) o 25 were put on new decks (smooth surface) o 18 are sSll in service o No Chloride PenetraSon
§ Asphalt Overlays in the ‘90s
o Did Not Use Waterproof Membrane o Consistently Poor Results o Department Realiza;on of the Importance of a Waterproofing Membrane in conjunc;on with an Asphalt Overlay on a Bridge Deck
1. Bridges with an exisFng asphalt overlay, will be Re-‐Overlaid with Asphalt.
2. Bridges with the life expectancy of less than 10 years, can get an asphalt overlay.
3. Waterproof Membrane is a MUST install with asphalt overlay.
4. NO asphalt patches on bridge decks.
NDOR’s ExisSng PracSce on Asphalt Overlay
2/17/16
2016 Nebraska Asphalt Paving Conference 2
§ Compare Overlay OpFons
Overlay type Cost ($/SF) Service Life (Expected)
Silica Fume $15 25
Asphalt with Membrane $4 10-‐15
Epoxy Polymer Overlay $8 10-‐15
§ Compare Overlay OpFons
Overlay type Deck CondiSon ProtecSon level
Silica Fume 5 or 6 Poor to Very Good
Asphalt with Membrane 5 or beXer Very Good to Excellent
Epoxy Polymer Overlay 7 or beXer Very Good to Excellent
The importance of deck protecFon: • With good deck protecFon applied early in a bridge’s service life it is possible
the deck can last for the full lifespan of the bridge.
• Without protecFon we know for sure that bridge decks will require major acFon (repairs or re-‐decking).
§ Asphalt with Membrane
Advantages
Low iniFal cost Short construcFon Fme Familiar material: easy to repair small failures. Flexibility of membrane provides protecFon for decks with movement related cracking. Overlay placed with mainline resurfacing (no paving interrupFon at bridge) Membrane can provide protecFon at joints for bridges with low movement. Asphalt can be tapered in lieu of inlay on bridge-‐only projects
Drawbacks
Hides deck for inspecFon. Can’t protect deck under open rails Rail height can limit thickness: • Need 32” minimum rail height on Interstate • Need 27” minimum rail height elsewhere
Preformed membrane is difficult to install on curved bridges and bridges with steep super elevaFons. For these applicaFons use spray-‐type membrane, (at higher cost) Need an asphalt plant
§ Overlays and Expansion Joints
There is no perfect joint: all joints can have problems Joints in overlays, except asphalt, follow same rules for Expansion joint selecFon as on a bare deck:
BOPP 3.1.7 Expansion Device Policy BOPP Expansion Device Policy doesn’t currently cover Asphalt Overlay joint selecFon. SPU pracFce is:
TM < 0.5” no expansion device required (they are considering reducing this to TM < 0.25”) TM between 0.5” and 1.0” use a 12” to 20” asphalt plug joint TM > 1.0” use built up concrete nosing and follow BOPP 3.1.7
2/17/16
2016 Nebraska Asphalt Paving Conference 3
§ Asphalt Plug Joint
§ Bridge Program on State Highway System
2 19
20 14 26
10 9
$0M
$10M
$20M
$30M
$40M
$50M
$60M
$70M
$80M
$90M
2016 2017 2018 2019 2020 2021 2022
Other
Culverts
Bridges
§ Asphalt Overlays with Membrane
$0
$500
$1,000
$1,500
$2,000
$2,500
$3,000
2009 2010 2011 2012 2013 2014 2015
Thou
sand
s
Asphalt Membrane
§ Asphalt and Membrane SpecificaSon EvoluSon
§ 2009-‐2011, 2 pages § Authored by M&R, SPU § End of Life on Maintenance Projects § InstallaSon Per Manufacturer's representaSve and in
accordance with the specificaSons § Stop Gap Measure
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2016 Nebraska Asphalt Paving Conference 4
§ Asphalt and Membrane SpecificaSon EvoluSon
§ 2011, 4 pages § Authored by BMS § PreservaSon of Bridge Decks § Significant Deck PreparaSon InstrucSons § Used 2012 – 2015
§ Asphalt and Membrane SpecificaSon EvoluSon
§ 2014 (Type A), 8 pages § Authored by BMS, M&R, ConstrucSon § PreservaSon of Bridge Decks § Significant changes to ConstrucSon Methods (CSP 5) &
Material ProperSes Table (percent elongaSon, polymeric thickness)
§ Never Let § Driven by Technological and Material Property changes in
the Advancing Industry
§ Asphalt and Membrane SpecificaSon EvoluSon
§ 2015 (Type A), 14 pages § Authored by BMS, M&R, ConstrucSon § PreservaSon of Bridge Decks § Added OpSon 1 and OpSon 2 deck preparaSon § 2015 (2/5/15 and 2/26/15 leengs by Addendum), 2015
(7 remaining leengs in contract) § OpSon 1 Similar to the previous version § OpSon 2 allowed for reduced deck preparaSon but
required a thicker 2 ply membrane
§ Asphalt and Membrane SpecificaSon EvoluSon
§ 2016 (Type 1), 7 pages § Authored by BMS, M&R, ConstrucSon § PreservaSon of Bridge Decks § Removed OpSon 2, single pay item "Preformed
Waterproofing Membrane", used on bridges with less than 15% deck area in need of roughness removal
§ 2016 (2/4/16 leeng by Addendum)
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2016 Nebraska Asphalt Paving Conference 5
§ Asphalt and Membrane SpecificaSon EvoluSon
§ 2016 (Type 2), 7 pages § Authored by BMS, M&R, ConstrucSon § PreservaSon of Bridge Decks § Removed OpSon 2, two pay items "Preformed
Waterproofing Membrane" and "Bridge Deck PreparaSon", used on bridges with more than 15% deck area in need of roughness removal
§ Never Let (yet)
§ Summary
§ Long History of Bridge Deck Membrane Use in NE § AnScipate Increased Use § Asphalt Plug Joints Use to ConSnue and Increase § High Quality ExpectaSons § More Than Willing to Work With the Industry to
Achieve High Quality Results
§ QuesSons? Comments?