adaptation and performance of hot mix asphalt recycling
TRANSCRIPT
INDIAN INSTITUTE OF TECHNOLOGY ROORKEE
International Conference Transportation Infrastructure Projects Conception To Execution
January 7-10, 2019
Authors
Ankit Sharma*, G.D. Ransinchung R.N.**, Praveen Kumar***
*Research Scholar, IIT Roorkee, India
**Associate Professor, IIT Roorkee, India
*** Director, NIT Delhi, India
Adaptation and Performance of Hot Mix Asphalt Recycling Technology in India and Abroad : A
Review
Content
• Why RAP Recycling?
• Development of RAP-HMA Technology.
• What are Rejuvenators?
• Status of RAP-HMA in India and Abroad.
• Specifications of RAP- HMA.
• Conclusions.
33
What is Next ?
44
Save the National Asset
RAP
Rejuvenators
55
Reclaimed Asphalt Pavement (RAP)
• Recycling of asphalt pavements by reclaiming them, called
Reclaimed Asphalt Pavement.
• Reclamation of pavement consist of adding softer grade of
binder, appropriate rejuvenators and virgin aggregates.
66
RAP is worth the virgin material it replaces.
Source : http://www.apa-mi.org/docs/RAP2012LRW.pdf
77
Economy using RAP material (5% Bitumen Content)
• Or 2860 Rupees per ton of RAP.
Quantity of RAP material
Total RAP 30,000 t
Bitumen 1500 t
Aggregates 28,500 t
Cost Saving by RAP material
Bitumen 630 Lacs
Aggregates 228 Lacs
RAP 858 Lacs
88
Cost variation on using RAP
Source: http://raptech.us/library/Asphalt-Professional-Nov-2014.pdf
99
Overlay can Experience Cracks and Rerutting
Source: https://www.h-a-d.hr/pubfile.php?id=792
1010
Milling and Inlays Prevent Rutting
Source: https://www.h-a-d.hr/pubfile.php?id=792
Overlay Changes Bridge Clearance
Milling creates a Grooved
Surface
Environmental Benefits.
Development of RAP Recycling
• Pre- 1970s: A Novelty (RAP)
• 1970- 1985: Rising to Meet a Need (RAP)
• 1985- 2006: Standard Practices (RAP and RAS)
• 2006- 2015: A Revival (RAP and RAS)
• 2015- Present: Balance Mixture Design Method
Pre- 1970s: A Novelty (RAP)
• Warren Brothers Co. started recycling at the
beginning of 20th Century.
• In 1931, Singapore rehabilitated road by
recycling and they lasted for 14 years before
World War- II.
• In 1948, recycling was used in Mumbai to
rehabilitate the roads, lasted for 30 years
before any subsequent reconstruction.
1970-1985: Rising to Meet a Need (RAP)
• The Arab Oil Embargo of mid- 1970 force
industries to find ways to save petroleum
cost.
• Rejuvenators have been used with RAP
materials.
• Researchers focused on technical aspects of
RAP recycling.
Ageing of Asphalt Pavement
Ageing !!!
• The use of RAP material is limited due to
stiffness and workability issues related to
RAP, hence rejuvenating cream or anti ageing
cream is used for asphalt called- rejuvenators.
Fig.: Rejuvenating action exampleSource : https://thumbs.dreamstime.com/z/beauty-skincare-concept-no-aging-wrinkles-14508503.jpg
Rejuvenators
• Rejuvenator are the material which soften the
aged RAP mix.
• Improves Cracking Performance without
compromising rutting performance.
Figure: Various rejuvenators
Central plant recycling (Little, Dallas N., Epps, 1980)
S.No. Rejuvenators RAP incorporation Pavement Layer
1 Cyclogen L (Recycling Oil) 100%, Surface, Base Course
2 AR- 2000 and Extender Oil 80% Surface
3 AC- 10 70% Surface Course
4 AC (200/300 Pen) 50% Surface and Base Course
5 AR- 8000 and Paxole (Softening Agent) 100% Surface
6 AR- 2000 70% Surface
7 AC-5 85%, 93% Base, Surface
8 E.A. 11-M (Emulsified Asphalt) and AC-10 30-100% Base
9 AC-10 and Softening Agent 85-100% and 77-100% Surface
10 Cyclopave (Recycling Oil) 72% Surface
Evaluation of Rejuvenator’s
Effectiveness with Conventional Mix
Testing for 100% Reclaimed Asphalt
Pavement Mixtures
Martins Zaumanis, Rajib B. Mallick, and Robert Frank
M. Zaumanis and R. B. Mallick, Civil and Environmental Engineering Department, Worcester Polytechnic Institute, 100 Institute Road,
Worcester, MA 01609.
R. Frank, RAP Technologies, LLC, 217 Belhaven Avenue, Linwood, NJ 08221.
Sample Preparation
• Binder used in the study was extracted from RAP by using toluene
as a solvent.
RAP binder was extracted using Toluene.
Sample Preparation
+Plant Oils
Refined Tallow (9%)
Distilled Tall Oil (9%)
Organic Blend (9%)
Waste-derived oils
WEO Bottoms (18%)
WEO (18%)
Engineered Products
WEO+FT Wax (18%)
Traditional and Non-Traditional
Refinery Base Oil
Paraffinic Base Oil (18%)
Aromatic Extract (18%)
Naphthenic Flux Oil (18%)
1
2
3
4
5
6 7
8
9
Mixing Time : 40 minutes.Mixing Temp. 135˚C
2424
Bitumen Test Results
Rejuvenator Kinematic Viscosity @135˚C (mm2/s)
Extracted RAP binder 2054
Virgin Nutsar PG 64-22 474
Organic Blend 831
Refined Tallow 612
Paraffin Base Oil 379
Aromatic Extract 406
Naphthenic Flux Oil 699
WEO+FT wax 1006
WEO bottoms 2054
WEO 457
Distilled Tall Oil 893
2525
Rejuvenator dosages selection
2626
Conclusion
S. No. Rejuvenator Type Rejuvenator Percentage (%)
Low Temperature
Properties
1 Distilled Tall Oil 12.7 ✓
2 WEO 18.2 ×
3 WEO bottoms >20 ×
4 WEO + FT wax >20 ×
5 Naphthenic Flux Oil >20 ✓
6 Aromatic Extract 18.3 ✓
7 Paraffin Base Oil 18.3 ×
8 Refined Tallow 9.7 ✓
9 Organic Blend 11.2 ✓
1985-2006: Standard Practices (RAP)
• SuperPave Mix Design specification
reduced the usages of RAP due to
confounding impression of RAP material in
contractors mind.
• NCHRP 09-12 project includes the
performance of RAP by Superpave design
mixture criteria.
2828
RAP-HMA Production
Source: http://www.morerap.us/files/rap-summit-10-08/brock-maximizing-rap-use.pdf
2006- 2015: A Revival
• Petroleum price raised during Great Recession
in late 2008.
• FHWA established RAP Expert Task Group.
RAP- ETG
State DOTs1 FHWA2 AASHTO3 NAPA4 NCAT5
Brief Findings of Expert Group
• NCHRP 09-46 reported that asphalt mix upto50% RAP performed well w.r.t. climateconditions and traffic loading conditions.
• 30% RAP incorporated surface courseperformed equivalent to virgin mixture.
• Results from NCAT pavement Test Trackindicates improved performance in terms ofraveling and cracking by using softer gradeof bitumen.
2015- 2018: Balance Mix Design Method
Thermal Cracking
Softener
Thermal Cracking
Softener
Rutting Resistance
Softener
Balance Design
2015- 2018: Balance Mix Design Method
Adaptation of HMA recycling Technology in various
countries
Production of HMA and WMA in 2007–2012
Usages of RAP in intermediate layers: USA states
Usages of RAP in surface layers: USA states
• FHWA promotes recycling through “FHWA Recycled Materials Policy” Administrator Message by Frederick G. Wright, Jr., Executive Director, FHWA.
• According to NAPA, by 2007, average RAP usages was 12%.
• By 2009, increased to 16.2%.• By 2012, increased to 20%.• Current guidelines for using RAP in Superpave mixes
were based on NCHRP Report 452.• For high RAP incorporation guidelines, NCHRP 09-46
Report can be referred.
RAP: USA
Recommended process for sampling and testing RAP samples
Ignition Method
Solvent Extraction Method
JMF for RAP
MDOT RAP Spec 12SP501 (G) 20112011 to Present (Superpave)
• Tier 1 - 0% to 17% RAP (binder replacement)– Use same grade (design binder grade)
• Tier 2 - 18% to 27% RAP (binder replacement)– At least one grade lower for the low temperature
– Optional- lowering the high temperature one grade
• Tier 3 - 28% RAP (binder replacement)– Use a blending chart to determine the high and
low temperature values
Source: https://www.fhwa.dot.gov/pavement/recycling/98042/07.cfm
Binder Selection Guidelines for RAP Mixtures According to AASHTO M 323
Sr. No. Amount of RAP Recommendation
1 <15% No change in binder selection.
2 15% to 25% Select virgin binder one grade softer than normal
(e.g., select a PG 58-28 if PG 64-22 would
normally be used)
3 >25% Refer blending chart provided in ASTM D4887,
2016.
Adaptation of HMA Recycling in India
• In India the first reclaimed asphalt pavement was constructed in 1948 which serves uninterrupted for 30 years.
• Recycling of Asphalt Pavement is the leading research in India right now in pavement sector.
• IRC : 37- 2012 guidelines on Cold Recycling of RAP material are based on South African Bitumen and Tar association (SABITA) and Asphalt Mix Manual (MS-14) by Asphalt Institute, USA.
• There is a need to formulate Mix Design Guidelines for Hot Mix Asphalt (HMA) and Cold Mix Asphalt (CMA) of RAP material for Indigenous conditions.
Selection of virgin grade of bitumen for recycling purpose (India)
Sr. No. Amount of RAP Recommendation
1 <20% Same as specified in IRC 111, 2009.
2 21% to 30% One grade softer than as specified in IRC 111,
2009.
3 >30% Refer blending chart provided in ASTM D4887,
2016.
Source : Draft prepared for Indian Roads Congress, 26 February 2013. “Tentative Guidelines for Hot Recycled Plant-mixed Dense Graded Bituminous Mixes”
Indian Technical Circulars
• Two technical circulars :1. 48/2010 "Use of Reclaimed existing bituminous
material to upgrade an existing bituminous pavement in NHAI project" dated 24-02-2010 (NHAI, 2010) and,
2. 100/2012: "Use of Reclaimed Asphalt Pavement (RAP) Materials" dated 04-05-2012 (NHAI, 2012)
• These have been issued to contractors by National Highway Authority of India (NHAI) for using RAP material in Surface or base/ binder course of main road or service road. Comptroller and Auditor General (C&AG) of NHAI demands consolidated details of RAP material at NHAI in a table given below:
Indian Technical Circulars
• Two technical circulars :1. 48/2010 "Use of Reclaimed existing bituminous
material to upgrade an existing bituminous pavement in NHAI project" dated 24-02-2010 (NHAI, 2010) and,
2. 100/2012: "Use of Reclaimed Asphalt Pavement (RAP) Materials" dated 04-05-2012 (NHAI, 2012)
• These have been issued to contractors by National Highway Authority of India (NHAI) for using RAP material in Surface or base/ binder course of main road or service road. Comptroller and Auditor General (C&AG) of NHAI demands consolidated details of RAP material at NHAI in a table given below:
Name of
State
Name of
PIU
Name of
Stretch
Length
(km)
Status of
use of
RAP (if
used)
Reason
for not
using RAP
Conclusions
• Cracking resistance lowers by increasing RAPcontent, but not universally true.
• Softer Grade Bitumen or Rejuvenators,improved Cracking Resistance.
• Moisture Susceptibility is not generallyaffected by RAP content.
• Lower levels of binder replacement, bindergrading remain same as of virgin binder.
Conclusions
• Higher levels of binder replacement,combined binder grading increases both thehigh and low temperature grades.
• Stiffness of mixture increased with binderreplacement.
• Rutting Resistance improved at all binderreplacement levels.
References
• An Overview of Recycling and Reclamation Methods for Asphalt Pavement Rehablitation. (1992). Annapolis, MD.
• Kandhal, P. S. (2016). BITUMINOUS ROAD CONSTRUCTION IN INDIA (2016th ed.). PHI Learning. Retrieved from https://www.phindia.com/Books/BookDetail/OTc4LTgxLTIwMy01MjU4LTI
• David E. Newcomb, J. A. E. F. Z. (2016). Use of RAP & RAS in High Binder Replacement Asphalt Mixtures : A Synthesis. Retrieved from http://driveasphalt.org/assets/content/resources/SR213_-_RAP-RAS_Synthesis-lr.pdf
• Wright, F. G. (2015). Administrator’s Message “FHWA Recycled Materials Policy”. Retrieved December 15, 2018, from https://www.fhwa.dot.gov/legsregs/directives/policy/recmatpolicy.htm
• Willis, J. R., & Marasteanu, M. (2013). Improved Mix Design, Evaluation, and Materials Management Practices for Hot Mix Asphalt with High Reclaimed Asphalt Pavement Content. WASHINGTON, D.C. https://doi.org/10.17226/22554
• E-C 188, T. R. C. (2014). Application of Reclaimed Asphalt Pavement and Recycled Asphalt Shingles in Hot-Mix Asphalt: National and International Perspectives on Current Practices. In Transportation Research Circular E-C188 (p. 78). Transportation Research Board. Retrieved from http://onlinepubs.trb.org/onlinepubs/circulars/ec188.pdf
Thank You ☺
The science of recycled materials for road work is still relatively new. As the technology
continues to be improved, the use of RAP will become even more widespread, and the
environmental benefits will climb.