|
|
|
Title: EVALUATION OF PARTICLE SHAPE AND TEXTURE: MANUFACTURED VERSUS NATURAL SANDS
Accession Number: 00616321
Record Type: Component
Availability: Find a library where document is available Abstract: Many highway agencies now limit the amount of natural sand in hot mix asphalt (HMA) when used on heavy-duty pavements to minimize rutting. This procedure is usually accomplished by generically specifying the maximum allowable percentage of natural sand. Generally, natural sands tend to be rounded whereas manufactured sands tend to be angular. However, there are some natural sands that are subangular rather than rounded. Also, some manufactured or crushed sands can be subrounded rather than completely angular. There is a definite need to quantify the shape and texture of the fine aggregate so that it can be specified on a rational basis rather than generically. Fine aggregates (8 natural and 10 manufactured sands) of different mineralogical compositions were sampled from various sources in Pennsylvania. Particle shape and texture data were obtained using ASTM D3398, and two proposed methods of the National Aggregate Association (NAA). On the basis of ASTM D3398, a particle index value of 14 appears to divide the natural and manufactured sands, and therefore, can be used for specification purposes. However, because each sieve size fraction needs to be tested individually and results combined, the current ASTM D3398 test procedures are too time consuming. However, test data indicate that only the major fraction needs to be tested because its particle index has a fairly good correlation with the average particle index. Moreover, both NAA proposed Methods A and B show good correlations (R-squared equals 0.97) with the ASTM D3398 method. These methods are straightforward and less time consuming. Equations needed to compute ASTM D3398 weighted-average particle index values from two NAA methods are described.
Supplemental Notes: This paper appears in Transportation Research Record No. 1301, Factors Affecting Properties and Performance of Pavements and Bridges 1991. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
Monograph Accession #: 01407099
Authors: Kandhal, Prithvi SMotter, John BKhatri, Maqbool APagination: p. 48-56
Publication Date: 1991
Serial: ISBN: 0309051053
Features: Figures
(7)
; References
(18)
; Tables
(4)
TRT Terms: Old TRIS Terms: Subject Areas: Geotechnology; Highways; I36: Aggregates
Files: TRIS, TRB, ATRI
Created Date: Oct 31 1991 12:00AM
More Articles from this Serial Issue:
|
