Apresentação sobre o método de dosagem superpaveDescrição completa
Apresentação sobre o método de dosagem superpaveDescripción completa
método superpave
Algunos equipos controls superpaveDescripción completa
Apresentação sobre o método de dosagem superpaveDescrição completa
La presente monografía denominada Pavimentos Superpave es un trabajo resultado de la recopilación de información que se encontró en diversas investigaciones hechas en otros países. Se podrá…Descripción completa
Practical handbook for super pave program for pavement design. A preamble to attached software
AN ILLUSTRATED OVERVIEW NATIONAL ASPHALT TRAINING CENTER DEMONSTRATION PROJECT 101
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Descripción: Partituras para banda, Mix de Adolescentes
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para Banda Patronal
Superpave Asphalt Mix Design Louisiana State University Joshua Board
Purpose The purpose of Superpave Asphalt Mix Design is to ensure that the optimum amount of asphalt cement is selected in order to satisfy the prescribed volumetric and densification criteria. It is this criteria that will identify what the asphalt is used for in the field.
Significance There are two types of criteria that govern how and asphalt will be used, Volumetric and Densification. These criteria are set in order to make certain that an asphalt will perform up to the standards. The volumetric criteria that will be found include: voids in the total mix (VTM), voids in the mineral aggregate (VMA), and voids filled with asphalt (VFA). Densification will also be looked at which will measure the specific gravity at different stages of the compaction process including: the primary consolidation which represents the construction phase and secondary consolidation which represents the end of life performance. Examination of both the criteria will allow the engineer to select the appropriate asphalt content.
Superpave Asphalt Mix Design
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Equipment This experiment requires the following equipment:
1. A metric scale accurate to 0.1 gram. 2. A bowl or pan in order to thoroughly mix the sample. 3. An oven. 4. A mixer to evenly distributed asphalt cement over the entire sample aggregate. 5. A sample mold and test papers to prevent adhesion of the sample to the mold. 6. A funnel used to pour the sample into the mold. 7. A Superpave Gyratory Compactor.
Test Specs and Sample The sample of asphalt concrete is made up of 55% #57 SST, 20% #11 SST, and 25% gravel aggregate. An asphalt cement binder was also used with the following percentages: 4.7%, 5.4%, or 5.9%. The final weight of each sample was 4800 grams.
Superpave Asphalt Mix Design
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Test Procedure The experiment followed the following procedures: 1. Select the aggregate that is to be used as your sample and measure out the proper amounts. 2. Blend the aggregate to develop the aggregate structure. 3. Design the asphalt content a)
Compact the sample at three different asphalt cement contents.
b)
Determine the compaction energy (Ninitial, Ndesign) for each asphalt cement content, where N is the number of gyration applied by the laboratory compactor.
4. Compute the volumetric and densification properties for each asphalt content.
Superpave Asphalt Mix Design
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Analysis of Results The data produced by the experiment resulted in the following values which are shown below in Table 1 and 2. Table 1 shows the measured values for the experiment and Table 2 contains the calculations for volumetrics and densification. Table 1- Measured Values
From Figure 1, the optimum asphalt content at 4% air voids is found to be 5.35%. This asphalt content is then used in Figures 2 through 5 in order to calculate the volumetric and densification properties of the sample. The optimized values for volumetrics and densification calculated from Figures 2 – 5 are: VFA is 72%, VMA is 13.93 %, Gmm(initial) is 86.6% and Gmm(final) is 97.6 %.
Superpave Asphalt Mix Design
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Findings For this Superpave Asphalt Mix Design laboratory, it was determined from a graph of air voids vs. % asphalt content that the optimum asphalt content at 4% air voids is 5.35%. The volumetric requirements for this aggregate state that the voids filled with asphalt must be between 70% and 80%. From Figure 2 using the 5.35% AC, it is shown that the VFA is between 70 and 80% and the optimum value is 72%. Figure 3 shows a graph of Voids in Mineral aggregate vs. % asphalt content. The minimum value for VMA is found to be 13.9 which corresponds to a nominal maximum aggregate size of 12.5 mm. The optimum VMA = 13.93%. The densification requirements for this lab are: Gmm(initial) < 89% and Gmm(final) < 98%. From Figure 4, it is shown that at 5.35% asphalt content, the Gmm(initial) = 86.6% and from Figure 5, the Gmm(final) = 97.6%. Both numbers are within the specified requirement. Since all requirements are met by the optimum asphalt content of 5.35%, this must be a correct % asphalt content.
Superpave Asphalt Mix Design
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Sample Calculations Volumetrics: Air Voids:
VTM = ((2.438 – 2.372)/2.438)*100 = 6.0
Voids filled with asphalt:
where:
VFA = Mixture voids filled with asphalt VTM = Mixture air voids content
VFA = ((14.6 – 6.0)/14.6)*100 = 58.6 % Voids in the Mineral Aggregate
where:
VMA = Mixture Voids %AC = Asphalt percent
VMA = (1 – ((2.327)(1-0.04)/(2.553))*100 = 14.6 % Densification: Mixture Density at Ninitial: Given N = 9
%Gmm(N,9) = ((100)(114.2/128.6)(2.327))/2.438 = 84.8% Mixture Density at Nfinal: Given N = 125
