Issue 61

A. Kostina et alii, Frattura ed Integrità Strutturale, 61 (2022) 1-19; DOI: 10.3221/IGF-ESIS.61.01

Parameter

Value 1000

Unit

kg/m kg/m kg/m

 l  i  s

3

917

3

2215 4180 2090 850 0.58 2.22 1.62

3

c l c i c s λ l λ i λ s L

J/(kg·K) J/(kg·K) J/(kg·K) W/(m·K) W/(m·K) W/(m·K)

334560 1.4·10 -10

J/kg m/s

k 0

-5.5

- -

 

-2

a T

5·10 -7

1/K MPa MPa MPa

K fr

4.4 1.9 2.9

K un G fr G un

1.25 MPa Table 1: Parameters of soil used for the simulation of the Mizoguchi’s test.

Fig. 1 shows the effect of the mesh size on the relative tolerance. The results demonstrate that the relative error decreases with the increase in number of elements. The relative tolerance becomes constant when total number of elements exceeds 1875 which corresponds to the 75 elements along the lateral side of the computational domain and 25 elements along the top of the computational domain.

Figure 1: Relative tolerance vs number of elements.

Fig. 2 presents porosity distribution along the sample height measured in the test and obtained by numerical simulation for 12, 24, and 50 hours of the freezing. The presented plots can be divided into three stages. In the first stage, the porosity rises and the temperature of the soil is less than the freezing temperature T ph . Therefore, at this stage frost heave of the soil is occurred due to the phase transition of water into ice and water inflow. In the second stage, the temperature is also less than T ph , but the porosity significantly reduces to a minimum value. It indicates that there is an intensive water migration

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