Fine Graded Polymer Asphalt Concrete Pavements of Ohio ... partnering with the Ohio DoT a test...

Fine Graded Polymer Asphalt Concrete

“Ohio’s Smoothseal” Cliff Ursich, PE

Flexible Pavements of Ohio

¨ Product Development

¨ Description of Candidate Projects

¨ Materials Characterization

¨ Thickness Guidelines

¨ Manufacturing and Placement

¨ Typical Applications

¨ Deployment / Education

Ohio DOT’s Fine-Graded Polymer Asphalt Concrete - Smoothseal

¨ Product Development 4Developed and deployed in the early 1990’s by

Ohio’s asphalt paving industry in partnership with the Ohio Department of Transportation.

4Development was in response to growing interest in preventive maintenance practices.

4Looking for a hot-mix product that… 1. Could be placed in thin lifts to lower the cost per

square yard, 2. Could be manufactured by any contractor using

locally available materials (i.e. no special license required),

3. Was cost-competitive with other preventive maintenance products.


¨ Product Development 4Where do we start? ú Survey of state associations



4Where do we start?

ú Survey of state associations

ú NAPA pub. on thin-lift mixes

ú Ohio DOT’s Ralumac specification then known as Latex Modified Emulsified Asphalt (SS807)


¨ Product Development - 1991 4Gradation and binder type of SS 807 served as

the launching point for development.

4Marshall method utilized for design.

4Sought a mix type rich in binder, mix volumetrics that would ensure good durability. Latex was added for this purpose.

4Performance tests were not readily available so partnering with the Ohio DoT a test project was constructed.


The Smoothseal texture


1992


1993



4FHWA PM initiative in 2002 creates renewed interest in preventive maintenance.

4The Ohio DoT develops a catalog of treatment options and methodology for their use based on pavement condition rating; included is Fine-Graded Polymer Asphalt Concrete (a.k.a. Smoothseal)

4Smoothseal is elevated from proposal note to Supplemental Specification 854.


¨ Product Development - 2005 4Smoothseal is accepted as a standard

specification.

4Governed by ODOT, Item 424, Fine Graded Polymer Asphalt Concrete

4For use as a pavement preservation (PM) treatment

4Since 2002 in excess of 1.2 million tons placed*

* Represents material sold on ODOT contracts.

Does not include tonnage sold on local government contracts.





¨ Description of Candidate Projects 4Pavements suitable for a surface treatment

overlay show the following distresses: § Dry-looking, “bony” pavements that are porous

or permeable

§ Pavements that have begun to ravel

§ Pavements with extensive cracking too fine for crack sealing

§ Pavements with cracking of the surface too extensive for crack sealing alone

§ Pavements where curb reveal does not permit heavy lift thicknesses

Smoothseal - Ohio DOT’s Fine-Graded Polymer Asphalt Concrete


¨ Description of Candidate Projects 4Candidate pavements will have...

§ No unrepaired structural (fatigue) damage

§ No appreciable rutting (< ¼ inch)

§ Sufficient remaining structural capacity to last the life of the treatment

Note:

ú Rapidly deteriorating pavements are not good candidates for PM. Rapid deterioration is indicative of inadequate pavement strength.

ú Not intended as a crack attenuating layer.






¨ Materials Characterization 4Types of Smoothseal § Type A

Mix Design - Recipe mix (all traffic types) § Type B

Mix design – Volumetric mix design (light, medium, or heavy traffic pavements)


¨ Materials Characterization 4Types of Smoothseal § Type A

Composition:

Blend of sands w/ 8.5% polymer modified asphalt binder (76-22 SBS or 64-22 w/5% SBR)

Silicon dioxide requirement on the fine agg. ensures good skid resistance

Highest polymer dosage used in Ohio’s market enhances mix toughness, stability, and longevity

Smoothseal - Ohio DOT’s Fine-Graded Polymer Asphalt Concrete


0 200 30 8 4 3/8 1/2 3/4

30 20 10

40 50

60 70 80

90 Item 424, Type A

1/2 inch 3/8 inch 100 No. 4 95-100 No. 8 90-100 No. 16 80-100 No. 30 60-90 No. 50 30-65 No. 100 10-30 No. 200 3-10

• Materials Characterization Type A


¨ Materials Characterization 4Types of Smoothseal

§ Type B Composition:

½-inch max. sized coarse agg. and sand particles w/ min. polymer binder content of 6.4% (76-22 SBS or 64-22 w/5% SBR)

100% two-faced crushed coarse agg. for heavy traffic mixes to provide stability

Silicon dioxide requirement on the fine agg. ensures good skid resistance


¨ Materials Characterization 4Types of Smoothseal

§ Type B Composition (continued):

Highest polymer dosage used in Ohio’s market enhances mix toughness, stability, and longevity

10% RAP permitted


0 200 30 8 4 3/8 1/2 3/4

30 20 10

40 50

60 70 80

90 Item 424, Type B

1/2 inch 100 3/8 inch 95-100 No. 4 85-95 No. 8 53-63 No. 16 37-47 No. 30 25-35 No. 50 9-19 No. 100 No. 200 3-8

• Materials Characterization

Type B


0 200 30 8 4 3/8 1/2 3/4

30 20 10

40 50

60 70 80

90 Item 424, Type B

1/2 inch 100 3/8 inch 95-100 No. 4 85-95 No. 8 53-63 No. 16 37-47 No. 30 25-35 No. 50 9-19 No. 100 No. 200 3-8

• Materials Characterization Type A Type B


0 200 30 8 4 3/8 1/2 3/4

30 20 10

40 50

60 70 80

90 Microsurfacing

3/8 inch 100 No. 4 85-100 No. 8 50-80 No. 16 40-65 No. 30 28-45 No. 50 13-25 No. 100 --- No. 200 5-15

• Materials Characterization Type A Type B


Types of Smoothseal


5954 54 53 52 52

63

46 49 50 49 52 56 56

02468101214

010203040506070

RIC

430

TRU

88

STA

93

PER

345

BUT

177

TUS

39

JEFF

7

LUC

23

LUC

475

SHE

75

LOR

20

COS

36

FAY

35

PIK

32

Pave

men

t Age

Ski

d N

umbe

r (rib

bed

tire) Skid # Age (years)







• Overlay thickness guidelines § Type A mix

– 5/8” < thickness < 1 1/8”

§ Type B mix – 3/4” < thickness < 1 1/2”

Note: Pavement surfaces having significant irregularity will require a leveling course or milling prior to placement of Smoothseal.








• Manufacturing and Placement 4Manufacturing Smoothseal will be

similar to other polymer-modified HMA § Greater heat during production

§ Elevated mix temperature at the project site - max. 350ºF

– Sufficiently hot to compact

– Not so hot so as to cause binder draindown

– At least 290ºF at time of compaction

§ Has been manufactured as WMA


• Manufacturing and Placement 4Placing Smoothseal § Heightened attention to factors affecting

pavement smoothness

§ Uniformity in production, temperature, mix delivery, head of material before the screed, and compaction all become critically important

§ Handling and raking should be minimized…very, very sticky mix!

§ Avoid feathering

§ Butt joints preferred for joint construction


• Manufacturing and Placement 4Ensuring a successful Smoothseal job § Place material on clean and dry pavement

§ Place material on pavement having a minimum 60ºF surface temperature

§ Ensure uniform application of tack coat, set prior to paving

§ DO NOT USE PNEUMATIC TIRE ROLLERS.

§ Construct hot longitudinal joints or seal cold joints with bituminous material thoroughly coating the vertical face without runoff









Paving Englewood city streets with Smoothseal - 2002

Smoothsealing SR82 in Cuyahoga County

North Coast Inland Bike Path Paved with Smoothseal, Type A

IR 675 Montgomery County – Smoothseal, Type B







¨ Deployment / Education


Thank you ! Clifford Ursich, PE

[email protected] www.flexiblepavements.org

An association for the development, improvement and advancement of quality asphalt pavement construction.

Date post:	31-Mar-2018
Category:	Documents
Upload:	voque
View:	217 times
Download:	3 times

Fine Graded Polymer Asphalt Concrete Pavements of Ohio ... partnering with the Ohio DoT a test...

Documents