Interpreting the suction stress profiles under steady-state conditions considering the independence of van Genuchten SWCC parameters

TL;DR

This paper investigates how independent variations of van-Genuchten SWCC parameters m and n affect suction stress profiles in unsaturated soils, proposing a method for conservative stability analysis.

Contribution

It introduces an analysis of the effects of independent m and n parameters on suction stress profiles and suggests a relationship for conservative geotechnical stability solutions.

Findings

Variation in m and n alters the number and spread of characteristic regimes.

The nature and trend of suction stress profiles change significantly with parameter variation.

A method for conservative stability assessment based on m and n relationships is proposed.

Abstract

Suction stress is a fundamental component for applying the effective stress principle in unsaturated geotechnical engineering problems. The present paper aims to understand how the suction stress profiles get influenced if the $m$ and $n$ parameter of the van-Genuchten SWCC model is completely independent. Through the analysis, it is well noted that for constant air entry value, if the $m$ and $n$ relationships are varied, not only the number and the spread of the characteristic regimes get influenced, but the nature and the trend of the suction stress profiles associated with the regimes also alter significantly. A suggestion of selecting the m and n relationships is proposed for obtaining conservative solutions for geotechnical stability problems. The relevance of considering the unconstrained m parameter is established by computing the tensile crack depth of the clayey slope under steady-state infiltration conditions.