Uncertainty Instability Risk Analysis of High Concrete Arch Dam Abutments

Table 2

Type and parameter value of main variables in the hazard surface model.

Variable	Type	Distribution	Parameter value
Upstream water level	Random	Normal
Rock unit weight of the wedge	Random	Normal
Friction coefficient of bottom surface 1740 m	Fuzzy	Triangular
Friction coefficient of fault f2	Random	Normal
Friction coefficient of fault f5	Random	Normal
Cohesion of bottom surface 1740 m	Fuzzy	Triangular
Cohesion of fault f2	Random	Normal
Cohesion of fault f5	Random	Normal
Side surface area of case 1 (m^2)	Fuzzy	Triangular
Bottom surface area of case 1 (m^2)	Fuzzy	Triangular
Side surface area of case 2 (m^2)	Fuzzy	Triangular
Bottom surface area of case 2 (m^2)	Fuzzy	Triangular
Side surface area of case 3 (m^2)	Fuzzy	Triangular
Bottom surface area of case 3 (m^2)	Fuzzy	Triangular

Note. and are the mean value and the standard deviation of variable , respectively; is a triangular fuzzy number, where and are the minimum limit and the maximum limit of variable , respectively, when cut set level and is the most possible value of variable .