Next Article in Journal
Conceptual Framework for Sediment Management in Torrents
Previous Article in Journal
Impact of Long-Term Reclaimed Water Irrigation on Trace Elements Contents in Agricultural Soils in Beijing, China
Open AccessArticle

An Insight into the Projection Characteristics of the Soil-Water Retention Surface

School of Civil Engineering, Wuhan University, Wuhan 430072, China
School of Civil Engineering, Xijing University, Xi’an 710123, China
Author to whom correspondence should be addressed.
Water 2018, 10(12), 1717;
Received: 25 September 2018 / Revised: 25 October 2018 / Accepted: 17 November 2018 / Published: 23 November 2018
(This article belongs to the Section Hydraulics)
PDF [5774 KB, uploaded 28 November 2018]


The soil-water retention surface (SWRS), which describes the variation of the degree of saturation (Sr) with suction (s) and void ratio (e), is of crucial importance for understanding and modeling the hydro-mechanical behavior of unsaturated soils. As a 3D surface in the Sres space, the SWRS can be projected onto the constant Sr, constant s, and constant e planes to form three different 2D projections, which is essential for establishing the SWRS and understanding its various characteristics. This paper presents a series of investigations on the various characteristics of the three SWRS projections. For the Srs and Sre relationships, (i) a tangential approximation approach is proposed to quantitatively capture their asymptotes, and (ii) a new criterion is presented to distinguish the low and high suction ranges within which these two relationships exhibit different features. On the other hand, a modified expression is introduced to better capture the characteristics of the se relationships. The various projection characteristics and the proposed approaches are validated using a wide set of experimental data from the literature. Studies presented in this paper are useful for the rational interpretation of the SWRS and the hydro-mechanical coupling behavior of unsaturated soils. View Full-Text
Keywords: unsaturated soils; soil-water retention surface; suction; projections unsaturated soils; soil-water retention surface; suction; projections

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Ye, Y.-X.; Zou, W.-L.; Han, Z. An Insight into the Projection Characteristics of the Soil-Water Retention Surface. Water 2018, 10, 1717.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Water EISSN 2073-4441 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top