ABSTRACT
Reliability-based design for internal stability limit states for geosynthetic mechanically stabilized earth (MSE) walls provides a more nuanced appreciation of the margin of safety for these systems compared to conventional factor of safety, partial factor, and load and resistance factor design (LRFD) approaches. The paper introduces the basics of probabilistic analysis and design for internal stability limit states for MSE walls using the example of geogrid reinforced soil walls. The general approach uses a closed-form solution for reliability index which is easily implemented in a spreadsheet. The paper demonstrates how bias statistics for tensile load and pullout model accuracy can be gathered from load measurements recorded from instrumented walls and found in laboratory pullout box test databases. The paper concludes with example calculations of the probabilistic margin of safety for tensile strength and pullout limit states using the AASHTO Simplified Method and the recent AASHTO Stiffness Method in the USA.
