Table 3. Test conditions and types of tests.

RESULTS AND DISCUSSION - SR99_140012

Table 6. Resilient modulus test results for NH1.

SR99_14
Page Navigation
7

Table 3. Test conditions and types of tests.

Test moisture/density

Resilient modulus

γd kg/m3 (pcf)

Table 4. Test temperatures for shear tests.

Test temperature (C)

103, 138 (15,20)

*Numbers in table are confining pressures in kPa (psi).

single value to represent the resilient modulus of

proximately 3.5 times less) in the resilient moduli

the subgrade, the test values are averaged at each

of the clay and the fine sand after thaw and before

temperature and presented in Table 11 and graphi-

freezing. It also appears never to regain strength.

cally in Figures 5 to 9. Analysis of the effect of con-

At positive temperatures, the resilient modulus

fining pressure, deviator stress, and temperature

remains constant.

on the resilient modulus is presented by Simonsen

It is well known that during the freezing and

et al. (in prep.). In all cases, as expected, the resil-

thawing process, the ground temperatures are

ient modulus increases significantly when the tem-

higher or lower than the air temperatures. Using

perature drops to below freezing. Observation of

the mean air temperature to determine the

the results indicate that the rate of change is larg-

monthly resilient modulus may produce signifi-

est between 0 and 2C for all soils during freez-

cantly different moduli values. The FROST model

ing and thawing. At temperatures below 2C, the

(Guymon et al. 1993) was used to estimate the tem-

difference in the resilient modulus during freez-

perature at the top of the subgrade. The top of the

ing or thawing is minimal. However, close to 0C,

subgrade was chosen since the current mechanis-

there are significant differences between the

tic model use the vertical strain at top of the

modulus obtained during the freezing and thaw-

subgrade as a failure criteria. Basically, the model

ing process. There is a significant decrease (ap-

is a one-dimensional vertical heat mass moisture

Table 5. Test temperatures for hydrostatic

compression tests.

Test temperature (C)

Western Governors University

Privacy Statement
Press Release
Contact

Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business