15 May 2001
Properties of Mineral Fibers1 (After NAPA 1994)
6 mm (.25 in.) max. mean text value
5 Fm (0.0002 in.) max. mean test value
250 Fm (No. 60) sieve
95 percent passing (min.)
63 Fm (No. 230)
65 percent passing (min.)
The European experience and development of the above criteria are based on the use of basalt
The fiber length is determined according to the Bauer McNett fractionation.
The fiber diameter is determined by measuring at least 200 fibers in a phase contract microscope.
Shot content is a measure of non-fibrous material. The shot content is determined on vibrating sieves.
Two sieves, No. 60 and No. 230, are typically utilized; for additional information see ASTM C612.
SMA Mix Design Requirements (After NAPA 1995)
(1) VTM, percent2
(2) Asphalt content, percent3
(4) Stability, N (lbs)
6200 (1400) suggested minimum
(5) Flow, 0.25 mm (0.01 inch)
(6) Compaction, number of blows at each side
of test specimen
(7) Draindown, percent5
0.3 max. (1 hour reading)
Marshall procedures are in accordance with AASHTO T 245 (ASTM D 1559).
VTM (voids in total mix or air voids) (see figure 2-12) is based on AASHTO T 166, T 209 (ASTM D
2041), and T 269 (ASTM D 3203). Maximum density will be based on AASHTO T 209 (ASTM D 2041).
Based on weight of total mix.
VMA (see Asphalt Institute Manual Series No. 2 (MS-2).
NCAT SMA asphalt draindown test (see paragraph 2.7,c, (1))
for SMA. These requirements are based on work done with the Federal Highway Administration
(FHWA) and others and published by the National Asphalt Pavement Association (NAPA).
(1) SMA asphalt draindown test. For the purpose of this test method, draindown is
considered to be that portion of the asphalt cement which separates itself from the sample as a whole
and is deposited outside the wire basket during the test. (Note, any noticeable aggregate particles that