displacement were measured. Model ice flexural strength was also determined using
cantilever beams. The displacement of infinite ice plate under the weight of specified mass was measured for the determination of the Young modulus. The mean
values of the ice properties are given in Table 2. Effective strain rate during
indentation tests is calculated as ε̇ = U ̸ 2D, where U is the horizontal velocity of the
indenter, D is the indenter diameter.
The stress intensity factor K 1c was found using the method described in the
KSRI reports [16, 17]. A cantilever beam with a cut in the root section was loaded
by a horizontal force applied to the beam end (Figs. 5 and 6). The force P that broke
the beam was recorded. The stress intensity factor was found from relation
K I c =
2PL
ffiffi
π
p
h i ðW − aÞ
1.5 , where L is the beam length, W is its width, a is the length of a cut
in the beam root.
The stress intensity factor was not determined for the sea ice by the described
procedure. In accordance with the data from various sources [2, 6] K Ic for the
one-year sea ice is within 115–200 kPa m
0.5 .
The sea ice salinity and temperature averaged through the ice thickness were
6.0 ppt and −4 °C, respectively. The temperature and salinity profiles across the
model ice thickness were not determined. The mean salinity of the model ice was
5.0 ppt.
Table 1 Tests matrix
Ice type
Beam#
Thickness
h (m)
Length
L (m)
Width
W (m)
W/
h
L/
h
Sea ice
Sea1_L
0.530
4.050
0.500
0.9
7.6
Sea2_M
0.550
3.000
0.500
0.9
4.6
Sea3_S
0.420
1.600
0.500
1.2
3.8
Model ice/FG fine
granule
FG1
0.050
0.345
0.050
1.0
6.9
FG2
0.050
0.260
0.050
1.0
5.2
FG3
0.050
0.180
0.050
1.0
3.6
Model ice/columnar
Col3
0.053
0.355
0.045
0.8
6.7
Col4
0.053
0.260
0.045
0.8
4.9
Col5
0.053
0.100
0.060
1.1
1.9
Col6
0.053
0.175
0.052
1.0
3.3
Table 2 Ice properties (mean values)
Ice type
Flexural
strength
(kPa)
Indentation
pressure (kPa)
Indentation
strain rate (1/s)
Young
Modulus
(MPa)
Stress intensity
factor (kPa m
0.5 )
Sea ice
345.0
4000
3.5E−03
1200
115–200
Model ice FG
fine granule
15.6
55.0
1.25E−01
16.2
0.18
Model ice
columnar
26.6
528.8
1.25E−01
24.0
5.84
596
M. Karulina et al.
cantilever beams. The displacement of infinite ice plate under the weight of specified mass was measured for the determination of the Young modulus. The mean
values of the ice properties are given in Table 2. Effective strain rate during
indentation tests is calculated as ε̇ = U ̸ 2D, where U is the horizontal velocity of the
indenter, D is the indenter diameter.
The stress intensity factor K 1c was found using the method described in the
KSRI reports [16, 17]. A cantilever beam with a cut in the root section was loaded
by a horizontal force applied to the beam end (Figs. 5 and 6). The force P that broke
the beam was recorded. The stress intensity factor was found from relation
K I c =
2PL
ffiffi
π
p
h i ðW − aÞ
1.5 , where L is the beam length, W is its width, a is the length of a cut
in the beam root.
The stress intensity factor was not determined for the sea ice by the described
procedure. In accordance with the data from various sources [2, 6] K Ic for the
one-year sea ice is within 115–200 kPa m
0.5 .
The sea ice salinity and temperature averaged through the ice thickness were
6.0 ppt and −4 °C, respectively. The temperature and salinity profiles across the
model ice thickness were not determined. The mean salinity of the model ice was
5.0 ppt.
Table 1 Tests matrix
Ice type
Beam#
Thickness
h (m)
Length
L (m)
Width
W (m)
W/
h
L/
h
Sea ice
Sea1_L
0.530
4.050
0.500
0.9
7.6
Sea2_M
0.550
3.000
0.500
0.9
4.6
Sea3_S
0.420
1.600
0.500
1.2
3.8
Model ice/FG fine
granule
FG1
0.050
0.345
0.050
1.0
6.9
FG2
0.050
0.260
0.050
1.0
5.2
FG3
0.050
0.180
0.050
1.0
3.6
Model ice/columnar
Col3
0.053
0.355
0.045
0.8
6.7
Col4
0.053
0.260
0.045
0.8
4.9
Col5
0.053
0.100
0.060
1.1
1.9
Col6
0.053
0.175
0.052
1.0
3.3
Table 2 Ice properties (mean values)
Ice type
Flexural
strength
(kPa)
Indentation
pressure (kPa)
Indentation
strain rate (1/s)
Young
Modulus
(MPa)
Stress intensity
factor (kPa m
0.5 )
Sea ice
345.0
4000
3.5E−03
1200
115–200
Model ice FG
fine granule
15.6
55.0
1.25E−01
16.2
0.18
Model ice
columnar
26.6
528.8
1.25E−01
24.0
5.84
596
M. Karulina et al.