Comparative analysis in the determination of experimental and numerical expansion pressure of an expansive soil

摘要

The behavior of the expansive soils is governed by the amount of water they contain, the variability of the water content keeps the soils in expansion-contraction cycles. The classical theories for the analysis of settlements do not take into consideration the behavior expansive soil, since they consider it totally saturated, this mean, they omit the efforts (expansion pressure) produced by the increase in volume (expansion). This phenomenon seriously affects light buildings that are built on expansive soils. Therefore, correct determination of the expansion pressure is of vital importance. There are two classifications of methods to measure expansion pressure: Direct and indirect. The direct methods (experimental) better represent the behavior of the soil, however, it requires to invest a considerable amount of time. The Indirect methods (numerical) are empirical, statistical or empirical-statistical equations applied with geotechnical properties, these methods are not very varied and do not generalize all soils. The purpose of this work is to carry out a comparative analysis of the indirect methods and compare them with the experimental results obtained by Galaviz-González (2013) through the ASTM D4546 standard. The comparative analysis shows that the vast majority of the indirect methods are not able to predict the value of the experimental expansion of the clay under study. However, the equation of Vanapalli et al. (2012) yields consistent values. Therefore, it will be necessary to be prudent when choosing an indirect method in determining the expansion pressure and thus invest a time in the experimental determination.