Soil moisture evaporation is one of the main processes of mass and energy exchange of soil-atmosphere
which has an important influence on soil engineering properties. It is also the direct cause of many engineering and environmental problems
however
this issue has never been taken into account in geoengineering disciplines. Based on the recent research achievements on soil moisture evaporation in other disciplines
the advances of some important aspects on this topic
i.e. soil moisture evaporation capacity determination
test method
evaporation process
influencing factors and theoretical model
are summarized and shown as follows: (1) To accurately determine the actual evaporation capacity of soil is one of the most important tasks in soil moisture evaporation study. Generally
there are two categories of methods: theory calculation and direct measurement; (2) To carry out evaporation test is an important approach to understand soil moisture evaporation process and the related mechanism. There are two categories of tests: laboratorial test and in-situ test. As compared
evaporation test by environmental chamber has better application prospect; (3) Soil moisture evaporation process can be divided into three stages: constant rate
falling rate and residual rate phases; (4) The factors influencing soil evaporation can be categorized as internal soil factors and external environmental factors. The former one mainly affects soil moisture transportation characteristics
and the latter one mainly influences evaporation energy supply intensity; (5) Many soil moisture evaporation calculation and prediction models have been proposed
however
they show some disadvantages such as large errors
narrow range of adaptation or difficulties on parameters acquisition. Based on the above understanding
and to combine with the research background of geotechnical and geological engineering
some important research topics that should be well investigated in future are proposed
including the evaporation mechanism of falling rate stage
the quantitative relationship between the soil properties and evaporation rate
soil moisture evaporation and transportation mechanisms in clayey soil especially in expansive soil
development of high precision in-situ soil moisture evaporation test apparatus and construction of universal soil moisture evaporation theoretical model.