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The first example is come from Arai and Tagyo's paper (1985). A simple slope, shown in Fig. 2, consists
of a homogeneous soil with zero pore pressure. The height and grade of slope are respectively 20m and
1:1.5. The computation parameters of soil are cohesion c=41.65kPa, angle of internal friction 0=15°, unit
weight Y = 18.82kN/m 3 . For the convenience of analysis, the slope is divided into 11 slices, each of which
has the width 6m as illustrated in Fig.2, and the spacing of nodes on each slice is 0.5m.
Figure 2 The computing results of Example 1
Based on the simplified Janbu's analysis method of slope stability and the present search technique of slip
surface, the location of the most dangerous slip surface is illustrated as the dash double-dot line in Fig.2,
and the factor of safety is 1.268. For explaining the accuracy of the present method, the Arai and Tagyo's
result obtained by the use of conjugate gradient technique is depicted as the solid line in Fig.2. The factor
of safety is 1.265. The Fig.2 shows that the results obtained by the present AACS are very consistent with
those given by the Arai and Tagyo's conjugate gradient search technique. This demonstrates that the
AACS is effective and reliable for stability analysis of slopes.
Example 2
An open-pit mine is located in gobi in Xinjiang Autonomous Region. In this mine zone, the mean annual
rainfall is 33.4mm, but the quantity of evaporation is as high as 3222.2mm. The difference of atmospheric
temperature between the day and night reaches up to 40°C, and the most difference during all year long is
about 76°C. The design height of slope at the northern part of the mine is 98m- 120m, and the inclination
angle of slopes is 44°C. The open-pit slope consists of crystalline lime-rock, marble, andesite, and iron ore.
The physical and mechanical parameters of rock mass, shown in table 1, are obtained by the laboratory test
and in-situ investigation. The influence factor of earthquake is 0.08.
TABLE 1
PHYSICAL AND MECHANICAL PARAMETERS OF ROCK MASS
Material
Crystalline lime-rock
Marble
Unit weight,
y
28.0kPa
28.1 kPa
Internal
friction,
9
36.6°
43.8°
Cohesion,
c
162.0 kPa
213.0 kPa
Influence Factor of
Earthquake, K c
0.08
0.08