Reliability and Uncertainty in Analysis of Rammed Earth Walls

Abstract

-This paper deals with reliability analysis and uncertainty of rammed earth (RE) structures as a widely used sustainable and environment-friendly structure. Due to lack of comprehensive design standards, the engineers often rely on "rule-of-thumb" methods, which leads to quite conservative or unsafe designs. In this study, uncertainty of load and resistance parameters were included in analysis of rammed earth structures. The reliability index and failure probability of RE structures were evaluated using First-OrderReliability-Method (FORM). The analysis was performed based on the different loads and resistance random variables parameters. Based on the results, the recommended wall thickness by various codes are quite conservative. On the other hands, larger wall thickness is required under severe loadings conditions. The compressive strength of unstabilized materials under severe loading conditions should be more than minimum recommended. The sensitivity analysis on the random variables indicates that the compressive strength and the environmental loads factors are the most important random variables that contribute to reliability of the structures.