Precision Estimates of AASHTO T265: Laboratory Determination of Moisture Content of Soils (2010) / Chapter Skim
Currently Skimming:
Pages 8-18
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 8... ...
6 CHAPTER 3- INTERLABORATORY TEST RESULTS AND ANALYSIS 3.1 Test Data The moisture data were received for four aggregate-soil blends: coarse with clay (CC) , coarse with silt (CS)
|
From page 9... ...
7 Table 3-1: Summary of Statistics of % moisture content of coarse aggregate with clay (CC) Sample Type # of Labs Target % Average % Sx CV % Repeatability (Sr)
|
From page 10... ...
8 data are shown shaded in Table D-1 and are shown in Figure D-2 of Appendix D Based on exceedance of h and k statistics, the results from the following numbers of laboratories were eliminated from the analysis: one laboratory for the blend with 4% moisture, two laboratories for the blend with 6% moisture, and one laboratory for the blend with 8% moisture.
|
From page 11... ...
9 6.0 % vs.
|
From page 12... ...
10 Table 3-5: Results of t-test for comparison of measured and target moisture content of CC blend Sample Type Comparison Computed t Degrees of Freedom Critical t Rejection Prob. (P) Decision Coarse Aggregate w/Clay (3%)
|
From page 13... ...
11 indicating that the measured and target values are not the same. As discussed previously, this significant difference between measured and target moisture content values might be due to loss of moisture during shipment of the mixtures with above optimum moisture content.
|
From page 14... ...
12 standard deviations of the clay and silt blends, at a specific moisture level, are not significantly different, they would be combined. In the second comparison, the combined standard deviations at different moisture levels will be compared for each gradation.
|
From page 15... ...
13 Table 3-10: Pooled repeatability and reproducibility standard deviations of the clay and silt blends Blend Type Moisture Content of the Blend Pooled Repeatability Pooled Reproducibility Coarse blend (Clay & Silt) 3% 0.04 0.06 Coarse blend (Clay & Silt)
|
From page 16... ...
14 3.4.2.2 Statistical Test on Standard Deviations of Various Moisture Levels The results of F-test at 1% level of significance for comparison of repeatability and reproducibility statistics of the coarse blends are presented in Table 3-13. As indicated from Column 5, Table 3-13, the rejection probabilities (p)
|
From page 17... ...
15 Table 3-14: Results of F-test on comparison of variability of moisture content measurements at various moisture contents, fine aggregate with clay (FC) , and fine aggregate with silt (FS)
|
From page 18... ...
16 Table 3-16: Results of F test for comparison of standard deviations of water content measurements of coarse and fine blends Compare Degrees of Freedom Critical F Computed F(Sr) Rejection Probability (SR)
|
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.