Sources of Uncertainty in Lateral Resistance of Slender Reinforcement Used for Slope Stabilization

Significant uncertainty remains in predicting the stabilizing forces that can be developed in slender reinforcing members used for slope stabilization. This uncertainty arises from the high number of potential failure modes as well as from uncertainties present in predicting the resistance contributed by the individual failure modes themselves. The aim of this research has been to identify the most significant sources of uncertainty in the design of slender reinforcement through parametric analyses so that the uncertainty can be addressed by modifications to current design and construction practice, and future research. Results of the parametric analyses showed that the degree of improvement in the factor of safety of a reinforced slope depends on a combination of the design parameters evaluated. The parameters with greater influence on the factor of safety for a given soil condition were slope inclination, method for predicting limiting soil resistance, and capacity of reinforcement used. While the uncertainty in limiting resistance for weak reinforcing members is greatly reduced due to the controlling effect of the structural failure mode, significant uncertainty still exists in predicting the limiting resistance on strong reinforcing members.