SLOPE STABILITY IN UNSATURATED LOW PLASTICITY SOILS USING THE BARCELONA BASIC MODEL (BBM) AND CALIBRATION OF TRIAXIAL TEST DATA

Moscoso L.R.V.; Rojas J.A.G.; Vasquez N.C.; Rojas E.L.P.; Chipana R.K.M. · Archives for Technical Sciences (2025) · DOI: 10.70102/afts.2025.1834.1206

Resumen

The stability of slope in unsaturated low plasticity soils is also a major issue particularly in areas where the level of water changes. This paper looks into how the Barcelona Basic Model (BBM) applies to the evaluation of the stability of a real slope that consists of low plasticity silt in the Chilca region, Peru. There was a complete characterization of soil in lab tests of index properties, water retention curves (WRC) and permeability characteristic curves (PCC) and triaxial tests at the unsaturated conditions. The parameters of BBM model were determined using an inverse methodology relying on the triaxial tests. CODE BIGHT software was used to perform numerical simulations aimed at measuring slope stability at different conditions of moisture and suction. The findings demonstrated that the BBM model forecasted the behavior of the slope with a good level of precision, the deviation of the deviatoric stress and the mean effective stress was only 0.68 % and 2.19 % in comparison to the field data. The sensitivity analysis showed that the cohesion parameter (κ) produced the most significant impact on the calibration accuracy, then the basic friction angle (φb) and suction adjustment parameter (r). The results validate the fact that the BBM model is an efficient method of predicting the stability of unsaturated low plasticity soils as it provides a useful alternative to more complicated, resource-consuming models. This study indicates that the BBM model has potentials in the geotechnical engineering applications especially in arid and semi-arid soils where soil suction is a critical factor in stability.

Instituciones: Universidad Privada del Norte