KEVIN DONNELLY , APM

DIRECTOR OF PAVEMENT PRESERVATION

CalAPA Tech Group San Diego, CA May 28, 2014

What is Pavement Preservation?

•  By applying a series of cost-effective treatments over the life of a pavement, agencies can treat more lane miles, preserve their system and increase customer satisfaction.

•  The cumulative effect of systematic, successive preservation treatments is to postpone costly rehabilitation and reconstruction.

Pavement Preservation is "a program employing a network level, long-term strategy that enhances pavement performance by using an integrated, cost-effective set of practices that extend pavement life, improve safety and meet motorist expectations."

Source: FHWA Pavement Preservation Expert Task Group

Developing A Healthy Transportation Network

Pavement Management

Pavement Preservation

Pavement Recycling

Preservation of good roads with low cost treatments saves big money– cost savings is then used to

repair poor roads.

Recycling with Engineered Emulsions saves 30% to 50% the cost over traditional

methods allowing more roads to be repaired with same to better performance

expectations over traditional approach

Roadway inventory, condition assessment, deterioration and work

history allows agencies to track performance,

develop political support of treatments and build

accurate models for future planning.

Treatments

Rejuvenating Fog Seal

Slurry Seals / Micro Surfacing

Chip Seal / Scrub Seal

Cape Seals

Scrub Membrane Interlayer

Recycles (CIR / CCPR)

Recycles (FDR)

Pavement Preservation Toolbox

70-100

60-80

25-70

25-70

20-50

0-50

0-40

Sound structural section

Sound structural section

Sound structural section

Fairly sound structural section

Fairly sound structural section

Fairly sound structural section

Failed / Partially failed structural section

PCI Use on 3-5 yrs

5-7 yrs

5-10 yrs

7-12 yrs

10-15 yrs

15-20+ yrs

Life Extension

Chip Seals and Scrub Seals are placed as: •  A “wearing course” meaning vehicles drive directly upon it; •  Part of a “cape seal” meaning a chip seal is first placed,

then covered by slurry seal or microsurfacing;

•  An “interlayer” meaning a layer between distressed underlying asphalt pavement and a new asphalt or rubberized asphalt surface.

What exactly is a scrub seal?

•  A scrub seal is a more advanced and aggressive multi-purpose chip seal. This rapid crack fill technique utilizes a specialized emulsion which is a polymer modified rejuvenating emulsion (PMRE) as the chip binder and rejuvenator in conjunction with a mechanized scrub broom that forces the optimum amount of emulsion into the cracks. The emulsion is not only highly polymerized which adds flexibility, toughness and durability but contains a recycling agent that conditions the aged surface while restoring the asphaltenes and maltenes balance.

Why Do Agencies Scrub Seal?

•  Cost effective surface treatment •  Eliminates the need to crack seal

-Less neighborhood disruption •  Protects underlying pavement •  Waterproofs the pavement surface •  Seals cracks and imperfections •  Provides a new wearing surface •  Restores surface friction •  Improves Aesthetics and lane

delineation •  Extends the service life

Mechanics

Some Common Types of Chip Seal Oils

CRS-2 CRS-2P PMCRS-2H HFRS-2 CHFRS-2 CHFRS-2P PMRE ARE PASS CR STYRAFLEX

TESTING OF EMULSIONS

Composition • Particle Charge • Density • Distillation

Storage and Handling • Storage Stability • Sieve • Saybolt Viscosity

Reactivity •  Demulsibility

Residue Tests •  Float Test •  Penetration •  Dynamic Shear

Rheometer

Benefits of Polymer Modified Emulsions or PME

Improved adhesion (less chip loss)

Improved resistance to flow at high temps

Improved flexibility at low temps

Longer service life

Chip seal failures usually occur in two forms: stripping (loss of cover stone) and bleeding (excess asphalt on the road surface). Many in the industry believe chip seals fail because emulsion and aggregate are not well suited to each other. Certain emulsions do work better with certain aggregates, but seldom - if ever - is the degree of compatibility between any emulsion and aggregate so poor that the asphalt will not coat the rocks. Most failures result from issues related to one of the following six aspects of chip seal construction, listed here with easy solutions: Aggregate and emulsion spread rates. Spread rates must be tailored to each project. Construction techniques. Properly adjusted and maintained equipment, proper timing, and good teamwork ensure quality chip seals. Weather. Hot, dry weather is best for proper emulsion setting and curing. Surface preparation. Repair and clean the road surface: fill potholes, level ruts, seal large cracks, repair broken edges, and scarify and recompact or stabilize an aggregate base, if necessary. If you chip seal over any of these problems, expect these problems to reappear in short time. Traffic control. Keep traffic under 25 mph until after the emulsion sets, the rolling has been done, and the first brooming is completed. Materials. Aggregate should be clean and dry, otherwise the emulsion won't adhere.

Source http://www.techtransfer.berkeley.edu/newsletter/05-4/sixsteps.php

Chip Seals and Scrub Seals are excellent Stress Absorbing Membrane Interlayer for subsequent treatments

•  Slurry Surfacing •  Micro-surfacing •  PME Chip Seals •  Thin Blanket HMA Overlays •  Warm Mix Asphalt Overlays •  Ultra-Thin Bonded Wearing Course

Think Remaining Service Life (RSL) when selecting roads

Double Chip Seal Red Rover Mine Road

Pre-Construction Discussion

Ordering Materials Material requirements § Min-max application temps

Weather Limitations Surface Preparation Cure Times Sweeping tips techniques

Broom set up Broom maintenance Attaching to distributor Adjustments to broom Amount of material to carry in the

broom How to work start/stops Bridges Joining passes

Pre-Construction Discussion

Striping tips Aggregate application construction sequence § How far between roller/spreader

Spray bar issues Traffic control Speed and weight effects on broom Rolling techniques

Equipment Needed to Perform a Chip Seal

Asphalt Distributor Truck Aggregate Distributor Dump Trucks Pneumatic Tire Rollers Brooms Tabs Traffic Controls

Caltrans District 8 Maintenance

Hwy 74

PASS CR 5/16” Scrub Cape Seal w/ Type II Slurry

Micro Mill, 5/16” RAP Scrub Seal with Type II RAP Micro Surfacing Escondido Canyon Road - Acton, CA

Micro Surfacing on Scrub Seal Stunt Road

Recycled Asphalt Pavement (RAP) Chip

•  Cost effective with best quality

•  Produce multiple products if possible

•  Single stones and conglomerations

•  Residual asphalt content will vary by sample

Crushed and screened 5/16” Rap aggregate

Thank you.

Kevin Donnelly, APM

Director, Pavement Preservation

kevin@westernemulsions.com

805-886-0900