Comparing the Volumetric and Mechanical Properties of Laboratory and Field Specimens of Asphalt Concrete (2016) / Chapter Skim
Currently Skimming:
Pages 6-23
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 6... ...
62.1 Phase I: Levels of Variability in Volumetric and Mechanical Properties of Asphalt Mixtures As part of the literature review for this study, data were collected from projects around the country which could be used to meet the objectives of this study. This research effort is referred to as Phase I throughout this document.
|
From page 7... ...
7 Aggregate gradation density was used as a quantitative method to identify mixes sensitive to minor changes in gradation and asphalt binder content and that may show greater variability between LL and PL specimens (D'Angelo and Ferragut 1991)
|
From page 8... ...
Properes State Aggregate Gradaon Mixture Performed by Air Voids Asphalt Binder Content Gmb Density VMA VFA Gmm Specimen Type Test Method Specimen Type Test Method Specimen Type Test Method Specimen Type Test Method Specimen Type Specimen Type Specimen Type Contractor State Third- Party CA PL - - PL - - - PF - - - - Y Y - FHWA PL PL - PL IO NC PL - - - PL PL PL - - Y FL PL PL SSD - - - - PF SSD PL PL - Y Y Y IL - PL SSD PL IO - - PF NC - - - Y Y Y IN - LL, PL SSD PL IO - - PF SSD PL - - Y Y - IA - PL - - - PF SSD - - PL - Y - KS - PL - - - - - PF - - - - Y Y - KY PL PL SSD PL, PF IO, SE, NC, BC PT PL, PF SSD PF NC PL PL - Y Y - LA(1)
|
From page 9... ...
IDT Tensile Strength Dynamic Modulus Flow Number Test Methods Source PL PF LL PL PF LL PL PF LL University of Arkansas X Louisiana X X MnROAD X X FHWA X X X X Table 2-2. Summary of data sets analyzed in task 2 (mechanical)
|
From page 10... ...
10 2.2.1 Data Analysis This section presents results of the individual analyses conducted for Arizona DOT (AZDOT) and University of Nevada, Reno, data sets as typical data sets as well as a summary of the entire data analysis.
|
From page 11... ...
11 Data ID Source Meta Designaon Specimen Type Status Comments 1 NCAT NT PL, LL Collected 2006 and 2009 Experiments 2 NCHRP Project 9-9 9.9 PL, PF Collected Data from 1999 to 2002 3 SPR – AZDOT AZ PL, LL, PF Collected Volumetric Properes 4 FDOT HVS FL PL, LL, PF Collected Experiments 5 and 6 FL PL and LL 5 Louisiana ALF LA PL, LL, PF Collected Experiments 1, 2, 3, and 4 6 WesTrack WS PL, LL, PF Collected Original and Rehabilitaon 7 LTPP LT PL, LL, PF Collected SPS 1 and SPS 91 8 WF Lands WF PF, PL, LL Collected Three projects 9 LA Gmm Study LA PF, PL, LL Collected Five projects 10 LA 98-1B Study LA PL, LL Collected Three projects 11 Un. Nevada -- -- PL, LL Collected No process-based factors2 12 NCHRP 9-22 -- -- PL, LL Collected No process-based factors2 13 California HVS -- -- N/A Not Collected Requests were turned down 1: SPS 1 had limited data and SPS 9 did not contain multiple specimen types.
|
From page 12... ...
12 Category Comparison Properes Average Differences Range AAD -Avg +Avg Min Max Volumetric PL-LL AC,% 0.19 -0.18 0.21 -0.51 0.65 PL-PF AV,% 0.64 -0.68 0.53 -0.98 0.70 Gradaon PL-LL 9.5 mm,% 2.49 -1.56 2.73 -2.43 5.33 2.36 mm,% 1.23 -1.24 1.22 -2.67 3.86 0.6 mm,% 1.88 -1.89 1.89 -5.00 4.57 0.075 mm,% 0.48 -0.61 0.40 -0.92 0.98 Table 2-10. AZDOT data set summary statistics.
|
From page 13... ...
13 -6 -4 -2 0 2 4 6 CW TG KS SR SW DWS BR TB CC PC Mixture ID 3.75-5.25 >5.25<3.75 -1.5 -1 -0.5 0 0.5 1 1.5 CW TG KS SR SW DWS BR TB CC PC Mixture ID 3.75-5.25 >5.25<3.75 ∆ = 0.
|
From page 14... ...
14 0 1 2 3 4 5 6 <3.75 3.75-5.25 >5.25 NSAD 9.5 mm 2.36 mm 0.6 mm 0.075 mm ∆ = Av g. │P as sin g P L P as sin g L L│ , % Figure 2-3.
|
From page 15... ...
15 Table 2-12. UNR delta summary statistics (Experiment 1)
|
From page 16... ...
16 Table 2-14. Summary of differences among the three specimen types for volumetric and gradation properties.
|
From page 17... ...
17 1.18 mm PF-LL 0.78 -- -- -- -- -- -PL-LL 1.538 1.078 -0.948 4.023 0.6 mm PF-LL 0.77 -- -- -- -- -- -PL-LL 1.721 1.25 -1.064 4.506 0.425 mm PL-LL 2.25 -- -- -- -- -- -0.3 mm PF-LL 0.73 -- -- -- -- -- -PL-LL 1.653 1.516 -1.777 5.083 0.18 mm PL-LL 2.75 -- -- -- -- -- -0.15 mm PF-LL 0.79 -- -- -- -- -- -PL-LL 0.855 0.541 -0.392 2.102 0.075 mm PF-LL 0.97 -- -- -- -- -- -PL-LL 0.617 0.388 -0.247 1.481 Percent Passing Sieve Size, % Comparison Average Differences Confidence Intervals AAD St.
|
From page 18... ...
18 Dynamic Modulus @ 70°F, 25Hz, 10Hz, 5Hz, 1HZ, 0.5Hz, 0.1Hz, % LL (PF-PL)
|
From page 19... ...
19 of the process-based factors. Some of the data grouped into the "meta-data" set did not originate from the same source, and the influences of unforeseen factors, such as mix design (i.e., NMAS)
|
From page 20... ...
20 -1.9% for the reheated group. Figure 2-6 shows the delta chart for aggregate gradation percent passing 4.75 mm grouped by reheating.
|
From page 21... ...
21 Figure 2-6. Meta-analysis: PL-LL aggregate gradation percent passing 4.75 mm (grouped by reheating)
|
From page 22... ...
22 Conclusions from the t-test may be affected by the large difference in the number of mixtures for each grouping. Figure 2-10 shows the delta chart for percent aggregate passing 0.075 mm grouped by reheating.
|
From page 23... ...
23 ric properties was mixed and was mostly inconclusive. Major limitations were encountered, because the collected data sets did not methodically vary most of the process-based factors identified as potential causes of variability.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.