Investigation of Methods for Improved Precision of Test Method Tex-113-e
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چکیده
15. Supplementary Notes Project performed in cooperation with the Texas Department of Transportation and the Federal Highway Administration. Project Title: Improving Correlation between Field Construction of Soils and Bases and Laboratory Sample Construction Techniques URL: http://tti.tamu.edu/documents/0-5135-1.pdf 16. Abstract The Texas Department of Transportation (TxDOT) employs the impact hammer method of sample compaction for laboratory preparation of road base and subgrade materials for testing. Serious concerns exist about the precision of the dry density obtained from this method. This report documents findings from efforts to improve the precision of Test Method Tex-113-E, TxDOT’s impact hammer compaction method for aggregate base materials. First, a new sample finishing tool replaced the old finishing method. While data from this change indicated a slight improvement in precision, the change did not hold up to statistical tests of significance. Additionally, four unique variations of laboratory preparation with the impact hammer method were investigated. All four methods resulted in the same mean dry density of compacted test specimens. However, two of the methods clearly resulted in poorer test precision.
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تاریخ انتشار 2005