5
Rate of Heave
Relative Frost
(mm/day)
Susceptibility
4
Negligible
0 - 0.5
Very Low
0.5 - 1.0
Low
1.0 - 2.0
3
Medium
2.0 - 4.0
High
4.0 - 8.0
Very High
> 8.0
2
1
0
2
4
6
8
10
PI, Plasticity Index
Figure 5. Relationship between PI and average rate of heave (1 in. = 25.4 mm).
does not identify the amount of the fine material
column of Table 7. The reliability indicates how
but the plasticity of the fines. What Table 6 sug-
well each criterion was able to distinguish be-
gests is that, in addition to the amount of fines, the
tween non-frost- and frost-susceptible materials;
plasticity of the fines can either increase or decrease
we used data generated by Kaplar (1974). For ref-
the frost-susceptibility of the material. Therefore, al-
erence, note that the reliability of the COE frost-
though the PI provides some idea of the frost-sus-
susceptibility criterion was 0.67 and 1.00 for classi-
ceptibility of the material, the amount of fines pass-
fying non-frost- and frost-susceptible soils.
ing the no. 200 sieve is the more critical parameter.
An analysis of Table 7 tells us that most states or
Several criteria for percentage passing the no.
provinces in cold regions limit the amount passing
200 sieve were evaluated and are listed in Table 7.
the no. 200 sieve to 10%. Also, the criterion of lim-
These criteria were obtained from Chamberlain
iting the amount of fines passing the no. 200 sieve
(1981) and are specifically for unstabilized base
to less than 7% had a reliability of 80% for frost-
and subbase materials. A material is considered
susceptibility prediction. The reliability for pre-
frost-susceptible if the amount passing the no. 200
dicting non-frost-susceptibility was in the range of
sieve exceeds the value presented in the second
40 to 80%.
Table 7. Criteria developed by others for predicting the frost-
susceptibility of soils.
Frost-susceptibility
Reliability
criteria
Non-frost-
Frost-
Agencies
(% passing no. 200 sieve)
susceptibility
susceptibility
Asphalt Institute
7
0.82
0.81
Newfoundland, Canada
6
0.60
0.82
Japan
6
0.60
0.82
Alaska
6
0.60
0.82
Colorado
510
0.67
0.75
Kansas
15
0.80
0.36
Maryland
12
0.80
0.45
Massachusetts
10
0.80
0.55
Minnesota
10
0.80
0.55
New Hampshire
8
0.80
0.45
Ohio
15
0.80
0.36
Vermont
10
0.80
0.73
Washington
10
0.80
0.64
Wisconsin
5
0.40
0.82
10
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