Comparison of Pore-Size Distribution of Soils Obtained by Different Methods

Abstract

An average size of pores and pore-size distribution (POSD) is often required for advanced constitutive models for soils adopted for hydro-mechanical-thermal coupled problems. There are a number of methods available for determining POSD, with most requiring specific testing equipment and expertise. In this paper, a comparison is made of POSDs obtained from two different techniques, viz, mercury intrusion porosimetry (MIP) and the pressure plate test (PPT). The former requires a specialists’ apparatus not commonly available in soil laboratories and also has safety issues, whereas the latter is more common because it is used to determine soil water retention characteristics of soils. On the basis of certain assumptions, it is demonstrated that POSDs obtained from the two techniques match well and PPT can be used by researchers in soil mechanics to obtain POSD. The range of pore sizes determined by the two techniques is, however, different. Also, the POSD obtained from other soil water retention curve (SWRC) techniques are compared with MIP data. A better correlation between POSDs and SWRCs can be observed.