During construction of the surface layer of asphalt pavement, two samples were taken every day to measure the asphalt content in the mix to ensure that it is within the specification limits. The target value was set at 5.5% with a tolerance of ±0.4%. The asphalt content data shown in Table P1.41 were collected: a. Calculate the mean, standard deviation, and the coefficient of variation of the data. b. Using a spreadsheet program, create a control chart for these data show- ing the target value and the upper and lower specification limits. Are the asphalt content data within the specification limits? Comment on any trend and possible reasons. TABLE P1.41 Date Asphalt Content, % Date Asphalt Content, % Oct. 15 Oct. 15 Oct. 16 Oct. 16 Oct. 17 Oct. 17 Oct. 18 Oct. 20 Oct. 20 Oct. 21 Oct. 21 Oct. 22 5.7 5.3 5.8 5.6 5.3 5.8 5.4 5.1 5.7 5.8 5.7 Oct. 22 5.9 5.6 Oct. 23 5.1 Oct. 18 5.8 Oct. 23 6.2 Oct. 19 5.4 Oct. 24 5.2 Oct. 19 5.5 Oct. 24 4.8

During construction of the surface layer of asphalt pavement, two samples were taken every day to measure the asphalt content in the mix to ensure that it is within the specification limits. The target value was set at 5.5% with a tolerance of ±0.4%. The asphalt content data shown in Table P1.41 were collected: a. Calculate the mean, standard deviation, and the coefficient of variation of the data. b. Using a spreadsheet program, create a control chart for these data show- ing the target value and the upper and lower specification limits. Are the asphalt content data within the specification limits? Comment on any trend and possible reasons. TABLE P1.41 Date Asphalt Content, % Date Asphalt Content, % Oct. 15 Oct. 15 Oct. 16 Oct. 16 Oct. 17 Oct. 17 Oct. 18 Oct. 20 Oct. 20 Oct. 21 Oct. 21 Oct. 22 5.7 5.3 5.8 5.6 5.3 5.8 5.4 5.1 5.7 5.8 5.7 Oct. 22 5.9 5.6 Oct. 23 5.1 Oct. 18 5.8 Oct. 23 6.2 Oct. 19 5.4 Oct. 24 5.2 Oct. 19 5.5 Oct. 24 4.8

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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Table shows the grain size distribution for two aggregates and the specification limits for an asphalt concrete. Determine the blend proportion requiredto meet the specification and the gradations of the blend. On a semilog gradation graph, plot the gradations of aggregate A, aggregate B, the selected blend,and the specification limits.c
Max specific gravity of mixture = 2.48 and following details are given. Bulk specific gravity aggregates in the mix and asphalt absorbed (%) are respectively, Material Specific gravity Mix Composition Asphalt Cement 1.02 6.40 Coarse Aggregate 2.51 52.35 Fine Aggregate 2.74 33.45 Mineral filler 2.69 7.80 2.603 and 3.10 2.538 and 2.60 2.603 and 2.08 2.538 and 3.20
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During construction of the surface layer of asphalt pavement, two samples were taken every day to measure the asphalt content in the mix to ensure that it is within the specification limits. The target value was set at 5.5% with a tolerance of +-0.4 ,. The asphalt content data shown in Table were collected: a. Calculate the mean, standard deviation, and the coefficient of variation of the data. b. Using a spreadsheet program, create a control chart for these data showing the target value and the upper and lower specification limits. Are the asphalt content data within the specification limits? Comment on any trend and possible reasons.
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