dc.description.abstract | In the design of engineering, the factor of safety often includes the influence of aleatory and
epistemic uncertainty. These two uncertainties are based on imperfect knowledge of engineering and
the randomness of soil in the soil layer. At the same time, the natural randomness uncertainty is the
main factor that affects the engineering design.
Taylor (1937) proposed the principle of stability number, using the friction circle method to
estimate the stability number at homogeneous finite slope. The stability number chart was proposed
through a series of calculations in different slope angles and friction angle of soil. Finally, we can use
the stability number to estimate the factor of safety at finite slope.
In this study, I use six types method of slices (Bishop、Morgenstern-Price、Ordinary、Spencer、
Janbu、Sarma) and combine with the principle of stability number to calculate stability number in
different slope angles (β = 20。~ 80。) and friction angles (ψ = 20。~ 80。). Moreover, I draw six kinds
of stability number charts by different methods of slices. Besides, I average m value (stability number)
from the results to make the average chart and select the maximum m value to propose a design chart
for estimating the most conservative factor of safety in six methods.
Finally, through the calculation of cases and the application of the Rosenblueth method, we can
verify the correctness of charts and quantify the influence of aleatory and epistemic uncertainty in the
factor of safety.
The simulation results show that the stability number charts proposed in this study can correctly
replace the method of slices so that we can more quickly calculate the factor of safety without
computer soft. From the calculation results of the Rosenblueth method, it can be seen that the
epistemic uncertainty has greater influence on the factor of safety than aleatory uncertainty. | en_US |