Crumb Rubber Life Cycle Cost Assessment (LCCA) Project

Crumb Rubber LCCA ProjectMichael R. Barr, Jesus M. Garza,

& Duy L. Nguyen

1

Introduction

• Demonstrating LCCA approach of AR

application to highway surfaces

• Determine total economic worth

– Initial and discounted future costs

• LCCA methodology for successful dialogue

– Differential costs of investment options

– Demonstrating sustainable commitment

2

Background

• Scrap Tire Management – a major

economic, environmental and social issue

• Asphalt Rubber – a proven technology and

superior performance product in highway

preservation

• Significance

– Useful, sustainable reclaimed products

– Reduction, management and/or elimination of

EH&S problems

3

Assumptions

Location: Central California, San Joaquin Valley, Visalia, Interstate 5 (I-5)

Project Type: Day Project, Application/Overlay of Rubberized Asphalt Concrete

(RAC) to Highway Surface

Comparison: Application/Overlay of Asphalt Concrete (AC) to Highway Surface

Work Zone: 5-mile stretch, 2-Lanes, Northbound and Southbound (4 Lanes total) =

20 Lane Miles

Material Type: Rubberized Hot Mix Asphalt Concrete (RAC), 2“ overlay to existing

highway surface

Comparison: Conventional hot mix asphalt (AC), 4“ overlay to existing highway

surface

[Note: 2:1 (AC:RAC) Equivalency Factor for resurfacing projects per Caltrans testing]

Options: Application of a Stress Absorbing Membrane (SAM):

Application of a Stress Absorbing Membrane Interlayer (SAMI)

Starting Capital: $10 million

4

Design Alternatives

• AC – Asphat Concrete

• RAC – Rubberized

Asphalt Concrete

• HMA overlay

• HMA mill-and-overlay

• 20 year pavement

design lives

5

Maintenance Options

Stress Absorbing Membrane (SAM)

Consists of a sprayed-on application of

heated straight-run binder, followed by a layer of aggregate chips that are precoatedwith asphalt rubber binder and seated with a rubber-tired roller

Utilizes asphalt rubber binder with 20% rubber

Greatly reduces the incidence of reflective cracking

Stress Absorbing Membrane Interlayer (SAMI)Consists of a SAM with a surface course of either rubberized or conventional hot mix asphalt

Also utilizes asphalt rubber binder with 20% rubber

Is used instead of SAM on high-traffic roads or when extra structural pavement capacity is needed

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Benefits

• Resists Cracking

• Reduces Road Noise

• Environmental Benefits

• Extends of road Surface

• Reduces Hydroplaning

• Cost Effective

$ $ $ $ $7

AC LCCA

8

RAC LCCA

9

Results

AC

• Initial Investment = $281,572.00

• Cost (O&M)

Maintenance = $847,616.5

Energy = $689.500.67

• Savings (and or Revenue)

Recycle = $56,508.36

• NPV = $16,683,921.30

• Sustainability details

CO2 Emissions = 773.04 tonnes

Energy = 6.41E+12J

RAC

• Initial Investment = $176,000.00

• Cost (O&M)

Maintenance = $387,695.62

Energy = $344,747.62

• Savings (and or Revenue)

Recycle = $31,017.65

• NPV = $14,350,494.38

• Sustainability details

CO2 Emissions = 375.88 tonnes

Energy = 3.12E+12J

10

Results

AC

• Initial Investment = $281,572.00

• Cost (O&M)

Maintenance = $847,616.5

• Savings (and or Revenue)

Recycle = $56,508.36

• NPV = $16,683,921.30

RAC

• Initial Investment = $176,000.00

• Cost (O&M)

Maintenance = $387,695.61

• Savings (and or Revenue)

Recycle = $31,017.65

• NPV = $14,350,494.38

11

Conclusions

Economic Environment Equity

Cost Effective GHG Reduction Reduce Insect Breeding Grounds

Reduces Raw Material Usage

Resource Conservation Reduce Fire Hazards

Speeds Construction Reduce Surface and Ground Water Pollution

Environmental Justice

Reduces Road Maintenance

Renewable ResourceUtilization

Performance Issues (Noise,Vibration, Hydroplaning, Vehicle Splash, Skid Resist.)

Reduces Liability

12

Asphalt Rubber: The Sustainability Effect

Recommendations

• When life cycle cost effective, AR overlays

for highway resurfacing typically yield 10-

25% cost savings

• Project’s limited scope: consider design

alternatives for optimization.

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References

• Cooper, S. J. (2011, October). Asphalt pavement recycling with

reclaimed asphalt pavement (rap). Nwpma, 18th annual fall pavement

conference, Portland, OR.

• Entech asphalt rubber. (2010). Retrieved from

http://www.4entechasphaltrubber.com/about_asphalt_rubber.html

• Keches, C., & LeBlanc, A. (2007). Reducing greenhouse gas emissions

from asphalt materials. Unpublished manuscript, Science, Worcester

Polytechnic Institute ,

• Roschen, T. (n.d.). Asphalt rubber. Informally published manuscript, ,

Available from CalRecylce. Retrieved from www.calrecycle.ca.gov/

• rubberized asphalt concrete (rac) benefits. (2011, August 25).

Retrieved from http://www.calrecycle.ca.gov/tires/rac/Benefits.htm

• Shatnawi, S. (2012). Life-cycle cost analysis of flexible pavement

systems rehabilitated with the use of asphalt rubber interlayers.

Informally published manuscript,

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