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From page 6... ... . UIAIA uses three cameras to capture images from three orthogonal directions and build a 3-D shape of each particle; it automatically determines flat and elongated particles, coarse aggregate angularity, coarse aggregate texture, and gradation. Read the entire page →
From page 7... ... • It is based on the same concept as the FAA test and the uncompacted voids in coarse aggregates test. However, it requires more time and is less practical than these tests. Read the entire page →
From page 8... ... • Assumes idealized particle shape (ellipsoid) Read the entire page →
From page 9... ... The system measures the three dimensions of the aggregate particles. Images can be captured using different resolutions based on the particle size detected by the system. Read the entire page →
From page 10... ... The same sample used in the nondestructive tests was used by all operators and for all test replicates. Each sample of a coarse aggregate size was 1 kg, while each sample of a fine aggregate was 0.5 kg. Read the entire page →
From page 11... ... Evaluation of Repeatability and Reproducibility Repeatability and reproducibility of test methods were evaluated through measuring the characteristics of aggregate samples several times by single and multiple operators. The operators were uniformly trained on the application of the test methods and were provided with the same set of instructional guidelines. Read the entire page →
From page 12... ... Percentage of Fractured Particles in Coarse Aggregate ASTM D 5821 X X X % of Fractured Faces (PFF) Flat and Elongated Coarse Aggregates ASTM D 4791 X X X Flat Elongated Ratio (FER) Read the entire page →
From page 13... ... employed in the imaging-based systems. This approach allowed evaluation of the accuracy of the analysis methods irrespective of the characteristics of the image acquisition setup. Read the entire page →
From page 14... ... It was necessary to evaluate the correlations among the different test methods to identify analysis methods that are able Coefficient of Variation (CV) Characteristics Test Method Parameter Abbreviation Measured Parameter as Reported by Test Method Repeatability Reproducibility Uncompacted Void Content of Coarse Aggregate UCVCC Percent Uncompacted Void Content L L 0 Fractured Faces H H 1 Fractured Face M H Percent Fractured Faces PFF 2 Fractured Faces M H Camsizer CAMCONV Conv3 L L WipShape WSMACR Minimal Average Curve Radius L L University of Illinois Aggregate Imaging System UIAIA UIAI Angularity Index L L AIMSGRAD Gradient Angularity L L Aggregate Imaging System AIMS AIMSRAD Radius Angularity L L Angularity Buffalo Wire Works PSSDA-Large PSSDA-Large ROUND Average Roundness L L University of Illinois Aggregate Imaging System UIAIA UISTI Mean Surface Texture Index L L Aggregate Imaging System AIMS AIMSTXTR Texture Index M M Camsizer CAMCONV Conv3 L L Uncompacted Void Content of Coarse Aggregate UCVCC Percent Uncompacted Void Content L L Texture WipShape WSMACR Minimal Average Curve Radius L L CAMSPHT SPHT3 L L Camsizer CAMSYMM Symm3 L L AIMSFORM Form 2-D L L Aggregate Imaging System AIMS AIMSSPH Sphericity L L Shape/Parameter Buffalo Wire Works PSSDA-Large PSSDA-Small ROUND Average Roundness L L Flat and Elongated Ratio FER Percent of Flat and Elongated Particles L H Read the entire page →
From page 15... ... Classification of fine aggregate test methods based on repeatability and reproducibility. Analysis Method Description Texture Index Using Wavelet Used by AIMS analysis Software (AIMSTXTR) Read the entire page →
From page 16... ... Examples of the correlations of image analysis methods with angularity visual numbers are shown in Figure 3. Rittenhouse (13) Read the entire page →
From page 17... ... Using the capabilities of SPSS software, the analysis results from the 50 images of the coarse aggregate size of each aggregate type were used to cluster the analysis methods. The analysis methods were clustered on the basis of similarities or distances using Ward's Linkage method. Read the entire page →
From page 18... ... Accuracy of Test Methods A digital caliper was used to measure the three dimensions of 100 particles selected randomly from each of the aggregates 18 Coarse Aggregate Analysis Method 1 2 3 4 5 6 7 8 9 10 11 12 13 AIMSTXTR 1 1 1 1 1 1 1 1 1 1 1 1 1 AIMSGRAD 2 2 2 2 2 2 2 2 2 2 1 2 2 AIMSRAD 2 2 3 2 2 3 2 1 2 3 2 3 3 AIMSFORM 2 2 2 2 2 3 2 1 2 3 2 3 3 AIMSSPH 3 3 3 3 3 1 3 3 3 1 3 1 4 UIFER 4 4 4 4 4 4 4 3 4 4 4 4 1 UIAI 4 4 4 4 4 4 4 2 4 4 4 4 2 UISTI 4 4 4 4 4 4 4 2 4 4 4 4 1 FRFORM 2 2 2 2 2 3 2 1 2 3 2 3 3 FRANG 2 2 2 2 2 3 2 1 2 3 2 3 3 FRTXTR 2 2 2 2 2 3 2 4 2 3 2 3 3 ASPCTPRO 2 2 2 2 2 3 2 1 2 3 2 3 3 FRCTLPRO 2 2 3 2 2 3 3 1 2 3 2 3 3 ROUNDPRO 2 2 2 2 2 3 2 1 2 3 2 3 3 Table 13. Clustering of analysis methods (4 clusters) Read the entire page →
From page 19... ... Coarse aggregates in angularity classes estimated using Ward's Linkage. Analysis Method Features AIMSTXTR • Capable of separating aggregates with different texture characteristics. Read the entire page →
From page 20... ... Measurements of angularity and texture of coarse aggregates were compared with visual rankings of aggregates made by five evaluators with backgrounds in asphalt pavements, concrete pavements, geology, and petrographic analysis. These evaluators were provided with a form to fill with the rankings. Read the entire page →
From page 21... ... Table 20. Average visual rankings of coarse aggregates by evaluators. Read the entire page →
From page 22... ... Portability(c) Coarse Fine Uncompacted Void Content of Fine Aggregates AASHTO T 304 250 1 1 1 1 N/A 1 Uncompacted Void Content of Coarse Aggregates AASHTO T P56 500 1 1 1 1 1 N/A Compacted Aggregate Resistance (CAR) Read the entire page →
From page 23... ... 23 (a) Number of Characteristics and Test Methods (b) Read the entire page →
From page 24... ... 24 (a) Weights Comparing Test Methods to Characteristics (b) Read the entire page →
From page 25... ... 25 (a) Priority Vectors (b) Read the entire page →
From page 26... ... This section provides an example of how the AHP can be used to determine the ranking of test methods measuring fine aggregate angularity, and texture and shape of coarse aggregates. The first level in AHP is the overall goal, which is the satisfaction with test methods. Read the entire page →
From page 27... ... Fine Aggregate Angularity AHP was used to rank the test methods that measure fine aggregate angularity: uncompacted void content of fine aggregate (UCVCF) , compacted aggregate resistance (CAR) Read the entire page →
From page 28... ... The resulting priority vectors and the overall ranking of test methods used to measure fine aggregate angularity are presented in Table 29. 28 Comparison Scale Criterion Characteristic 1 3 5 7 9 2:1 X 3:2 X Repeatability/ Reproducibility 3:1 X 2:1 X 3:1 X 3:2 X 4:1 X 4:2 X Accuracy Coarse-Shape (Ratio of R2 groups) Read the entire page →
From page 29... ... Coarse Aggregate Shape AHP was used in this example to rank test methods that measure coarse aggregate shape parameters and dimensional 29 Characteristics of Test Methods R ep ea ta bi lit y R ep ro du ci bi lit y A cc u ra cy Pr ic e R ea di ne ss In te rp re t D at a Ea se o f U se Po rt ab ili ty A pp lic ab ili ty Repeatability 1 1 1 1 1 1 1 1 1 Reproducibility 1 1 1 1 1 1 1 1 1 Accuracy 1 1 1 1 1 1 1 1 1 Cost 1 1 1 1 1 1 1 1 1 Readiness 1 1 1 1 1 1 1 1 1 Interpret Data 1 1 1 1 1 1 1 1 1 Ease of Use 1 1 1 1 1 1 1 1 1 Portability 1 1 1 1 1 1 1 1 1 Applicability 1 1 1 1 1 1 1 1 1 Table 27. Comparison of the characteristics based on overall satisfaction with methods. Read the entire page →
From page 30... ... 30 Test Method Characteristic Test Method UCVCF CAR PSSDA-Small Camsizer AIMS UCVCF 1 1 3 1 1 CAR 1 1 3 1 1 PSSDA-Small 0.33 0.33 1 0.33 0.33 Camsizer 1 1 3 1 1 Repeatability AIMS 1 1 3 1 1 UCVCF 1 1 3 1 1 CAR 1 1 3 1 1 PSSDA-Small 0.33 0.33 1 0.33 0.33 Camsizer 1 1 3 1 1 Reproducibility AIMS 1 1 3 1 1 UCVCF 1 1 1 0.143 0.11 CAR 1 1 1 0.143 0.11 PSSDA-Small 1 1 1 0.143 0.11 Camsizer 7 7 7 1 0.33 Accuracy AIMS 9 9 9 3 1 UCVCF 1 1 9 9 9 CAR 1 1 7 9 7 PSSDA-Small 0.11 0.14 1 1 1 Camsizer 0.11 0.11 1 1 1 Price AIMS 0.11 0.14 1 1 1 UCVCF 1 1 3 3 3 CAR 1 1 3 3 3 PSSDA-Small 0.33 0.33 1 1 1 Camsizer 0.33 0.33 1 1 Readiness AIMS 0.33 0.33 1 1 1 UCVCF 1 1 5 5 5 CAR 1 1 5 5 5 PSSDA-Small 0.20 0.20 1 1 1 Camsizer 0.20 0.20 1 1 1 Interpretation of Data AIMS 0.20 0.20 1 1 1 UCVCF 1 1 3 3 5 CAR 1 1 3 3 5 PSSDA-Small 0.33 0.33 1 1 3 Camsizer 0.33 0.33 1 1 3 Ease of Use AIMS 0.20 0.20 0.33 0.33 1 UCVCF 1 1 3 3 3 CAR 1 1 3 3 3 PSSDA-Small 0.33 0.33 1 1 1 Camsizer 0.33 0.33 1 1 1 Portability AIMS 0.33 0.33 1 1 1 1 1 1 1 1 CAR 1 1 1 1 1 PSSDA-Small 1 1 1 1 1 Camsizer 1 1 1 1 1 Applicability UCVCF AIMS 1 1 1 1 1 Table 28. Comparison of test methods measuring fine aggregate angularity. Read the entire page →
From page 31... ... Table 31. Overall ranking of test methods measuring fine aggregate angularity for different accuracy levels of preference. Read the entire page →
From page 32... ... Overall ranking of test methods measuring coarse aggregate texture. Read the entire page →
From page 33... ... Table 36. Overall ranking of test methods for measuring coarse aggregate shape. Read the entire page →
From page 34... ... The slice-to-slice resolution in the out of plane direction was 0.8 mm per voxel length. The images to the left were obtained using X-ray CT; and the images to the right were thresholded to highlight aggregate particles. Read the entire page →
From page 35... ... The findings of the X-ray CT of aggregate shape analysis are summarized as follows: • SHS analysis indicated that traprock had the highest angularity and texture, followed by limestone, and then gravel. • Analysis of X-ray CT images was capable of discriminating among the angularity and texture of the different aggregates. Read the entire page →
From page 36... ... Aggregates' shape, angularity, and texture were measured using the three analysis methods that are part of the AIMS software: (1) sphericity as a 3-D measure of coarse aggregates, (2) Read the entire page →
From page 37... ... Coarse Aggregates Angularity Figure 12. Limits of groups (clusters) Read the entire page →
From page 38... ... Coarse Aggregates Shape (Sphericity) Figure 12. Read the entire page →
From page 39... ... 02000 4000 6000 8000 10000 12000 Rounded Sub-Rounded Sub-Angular Angular Upper Limits for Gradient Angularity Classes G ra di en t A ng u la rit y Coarse-ALL Fine-ALL Coarse-Avg Fine-Avg (e) Coarse and Fine Aggregates Angularity R ou nd ed Su b R ou nd ed Su b A ng u la r A ng u la r2100 4000 5400 Fl at / El on ga te d Lo w Sp he ric ity M od er at e Sp he ric ity H ig h Sp he ric ity0.6 0.7 0.8 1.0 Po lis he d Sm oo th Lo w R ou gh ne ss M od er at e R ou gh ne ss H ig h R ou gh ne ss 165 275 350 460 Angularity Shape Texture Figure 12. Read the entire page →
From page 40... ... Form in Coarse Aggregate (a) Texture in Coarse Aggregate Figure 14. Read the entire page →
From page 41... ... had comparable angularity values but there was a significant difference in texture. The cumulative distribution of texture in the coarse aggregate samples shown in Figure 17 indicates that the texture of these aggregate samples was spread over a wide range; none of the other characteristics had such a wide range. Read the entire page →
From page 42... ... Texture and Angularity of Coarse Aggregate Particles Figure 16. Variations in texture and angularity properties in coarse aggregates. Read the entire page →
From page 43... ... Figure 18. Examples of the effect of coarse aggregate size on texture. Read the entire page →
From page 44... ... 44 0 10 20 30 40 50 60 70 80 90 100 0 1000 2000 3000 4000 5000 6000 7000 8000 Angularity "Gradient Method" Pe rc en ta ge o f P ar tic le s, % FA-2-#8 FA-2-#16 FA-2-#60 AngularSubAngularRounded SubRounded 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Short/Intermediate = Flatness Ratio In te rm ed ia te /L on g = E lo ng at io n Ra tio CA-2 CA-4 SP=0.5 SP=0.6 SP=0.7 SP=0.8 1 : 5 1 : 3 Ratio of shortest to longest axes Particles Become Less Flat Pa rti cl es B ec om e Le ss E lo ng at ed Figure 19. Example of the effect of fine aggregate size on angularity. Read the entire page →

From page 6...

... . UIAIA uses three cameras to capture images from three orthogonal directions and build a 3-D shape of each particle; it automatically determines flat and elongated particles, coarse aggregate angularity, coarse aggregate texture, and gradation.