ITEM 443 STONE MATRIX ASPHALT CONCRETE
443.01
Description
443.02 Quality
Control Program
443.03
Composition
443.04 Mixing
443.05 Storage
443.06 Quality
Control
443.07
Construction
443.08
Acceptance
443.09 Basis of
Payment
443.01 Description. This work
consists of constructing a stone matrix asphalt concrete (SMA)
course consisting of aggregate, asphalt binder, and additives.
The
requirements of 442 and 446 apply
except as follows. Do not use the warm mix asphalt
method (402.04) for this item.
443.02 Quality Control Program. Update
the Quality Control Program meeting 403.03 to
include a section for how the quality control, production and placement of SMA will meet this specification. Submit the revised
program to the Laboratory with the SMA mix design to be approved.
443.03 Composition. Discuss the mix design
approach with the Laboratory during the mix design and prior to submittal.
A Design Limits. Submit a JMF to the
Laboratory which meets the requirements of Table 443.03.1
and Table 443.03-2.
Sieve size |
Total Percent Passing |
|
3/4 inch |
(19.0 mm) |
100 |
1/2 inch |
(12.5 mm) |
85 to 100 |
3/8 inch |
(9.5 mm) |
50 to 75 |
No. 4 |
(4.75 mm) |
20 to 28 |
No. 8 |
(2.36 mm) |
15 to 24 |
No. 50 |
(300 µm) |
10 to 20 |
No. 200 |
(75 µm) |
8 to 12 |
Property Description |
Specification |
Binder, % [1] |
5.8 to 7.5 |
VMA, % [2] |
16.0 to 19.0 |
Draindown Test, % [3] |
0.3 |
Design Air Voids, % |
3.5 |
Design Gyrations [4] |
65 |
VCA MIX / VCA
DRC [5] |
< 1.0 |
TSR [6] |
0.80 |
F/A |
NA |
[1] By total mix
[2] Based on bulk gravity
[3] AASHTO T305
conducted at mix production temperature (not compaction temperature)
[4] Nini and Nmax do not apply
[5] VCA =
Volume of Coarse Aggregate (Calculated for mix and dry rodded
conditions according to AASHTO PP41- 02 or newer version.)
[6] Unconditioned specimens will have a
minimum 65 psi (450 kPa) retained strength.
Compact specimens at 300 °F (149 °C) for
PG 70-22M and 310 °F (154 °C) for PG 76-22M.
B. Asphalt Binder. Provide asphalt
binder conforming to 702.01.
C. Coarse Aggregate. Use approved
coarse aggregates. Ensure coarse aggregates meet 703.05 and Table 443.03-3.
TABLE
443.03-3 AGGREGATE REQUIREMENTS
Tests |
Description |
Specification |
% Flat and Elongated Ratio at 3:1, (max. to min.) 5:1, (max. to min.) |
20 max 5 max |
|
% Crushed, one / two faces |
100 / 90 min |
|
LA Abrasion (stone or gravel) |
35 max |
D. Mineral Filler. Conform to 703.07. Use mineral filler in the JMF with a plasticity index (AASHTO T 90
) not greater than 4 (does not apply to hydrated lime). Reclaimed asphalt concrete pavement passing the 5/8 inch (16 mm) sieve may be used as filler only. Do not account for reclaimed asphalt concrete pavement binder content. Do not use quicklime (CaO). Do not premix filler with another aggregate. Cover mineral filler piles to protect from rain.TABLE 443.03-4 MORTAR TEST REQUIREMENTS
1. Fiber Length (max) 0.25 inches (6.35 mm)
2. Sieve Analysis – Alpine Sieve Method
3. Ash Content 18% non-volatiles (±5%)
5. Oil Absorption (times fiber weight) 5.0 (±1.0)
6. Moisture Content (max) 5.0%
1. Pellet size 1/4 cubic inch (maximum)
1. Average Fiber length (max) 0.25 inches (6.35 mm)
Average
Fiber thickness (max)
0.0002 inch (0.005
mm)
Passing No. 60 (250 µm) sieve 90
to 100 percent
Passing No. 230 (63 µm) sieve 65
to 100 percent
3. Degradation (max)* 30 percent
* (GeorgiaDOT-124/McNett)
- copy available from the Office of Materials Management, Asphalt section.
443.04 Mixing. Conform to the following
additional requirements.
443.05 Storage. Do not store the SMA at the plant for more than 2 hours. Do not exceed a mix temperature of 350 °F
(180 °C). Provide SMA
at a minimum of 300 °F (148 °C) when it arrives at the paver, unless otherwise
approved by the Laboratory. If draindown occurs shorten the storage time and increase the
fiber dosage.
443.06 Quality Control. Ensure an employee of the
Contractor with a Level 3 rating is at the plant or construction site during
production of the SMA for any test strips and through
at least one full production day satisfactory to the District.
443.07 Construction. At least 24 hours prior to
beginning a test strip meet with the Engineer and DET
and provide a written summary of steps taken to assure mix quality and
construction practices account for the special needs of SMA
production and placement. Send a copy of
the written summary to the Laboratory.
443.08 Acceptance. After accepting the test strips,
the Department will accept SMA according to 446.05.
443.09 Basis of Payment. The Department will pay for
accepted quantities of Stone Matrix Asphalt Concrete, complete in place,
including test strip, at the contract price as modified by 446.05, as
follows:
443
Cubic Yard
Stone matrix asphalt concrete, 12.5mm, PG70-22M, (446)
443 Cubic Yard Stone matrix asphalt
concrete, 12.5mm, PG76-22M, (446)