The NTIS website and supporting ordering systems are undergoing a major upgrade from 8PM on September 25th through approximately October 6. During that time, much of the functionality, including subscription and product ordering, shipping, etc., will not be available. You may call NTIS at 1-800-553-6847 or (703) 605-6000 to place an order but you should expect delayed shipment. Please do NOT include credit card numbers in any email you might send NTIS.
Documents in the NTIS Technical Reports collection are the results of federally funded research. They are directly submitted to or collected by NTIS from Federal agencies for permanent accessibility to industry, academia and the public.  Before purchasing from NTIS, you may want to check for free access from (1) the issuing organization's website; (2) the U.S. Government Printing Office's Federal Digital System website; (3) the federal government Internet portal; or (4) a web search conducted using a commercial search engine such as
Accession Number PB2013-102356
Title Continued Monitoring of Indiana's SPS9-A Site.
Publication Date Jul 2012
Media Count 41p
Personal Author A. Shah J. Olek R. S. McDaniel
Abstract This study was initiated to continue monitoring of the performance of five test sections placed in 1997 to compare the performance of Superpave asphalt mixtures with different binder grades and one test section designed using the Marshall mix design method. A previous study had evaluated the performance of these test sections for four years after construction. This study extended that evaluation period to 12 years. During that time period, cores were taken from each test section at 9.5 and 12 years in service. Cores were tested and analyzed to determine the volumetrics and low temperature cracking behavior of the mixtures. Additional cores were used to extract, recover and test the binder in the mixtures. Results showed that the air void content in the mixtures did continue to decrease up to about nine years then appears to have leveled off. Aging (stiffening) of the unmodified binders was observed through Dynamic Shear Rheometer testing of the recovered binders but not by the penetration test. The modified binder did not exhibit the same level of aging as the unmodified binders. Aging also affected the recovered low temperature binder grade of four of the six binders, but the other two seemed relatively insensitive to aging at low temperatures. Testing of field cores showed that all of the mixtures would be expected to show thermal cracking at 9.5 years and beyond; this was confirmed by field distress surveys. The mix with polymer modified binder showed the greatest amount of cracking, which began at an early age in the field; this was not expected and did not correlate well with the lab testing results for unknown reasons. The mix with 15% RAP was slightly stiffer than a companion control mix without RAP, but the difference in predicted cracking temperature was only 1 - 2DGC for the surface mixes. Based on these results, INDOT can continue to use Superpave mixes with confidence, especially when considering the fact that Superpave has continued to evolve and be refined since this project was constructed. The mixture with RAP has performed about as well as the virgin mixtures under heavy interstate traffic.
Keywords Asphalts
Construction materials
Design methods
Laboratory tests
Performance evaluation
Superpave mixtures
Transverse cracking

Source Agency Federal Highway Administration
NTIS Subject Category 50A - Highway Engineering
50C - Construction Equipment, Materials, & Supplies
43G - Transportation
Corporate Author Purdue Univ., West Lafayette, IN. Joint Transportation Research Program.
Document Type Technical report
Title Note Final rept.
NTIS Issue Number 1304
Contract Number SPR-3017

Science and Technology Highlights

See a sampling of the latest scientific, technical and engineering information from NTIS in the NTIS Technical Reports Newsletter

Acrobat Reader Mobile    Acrobat Reader