Use of capillary action to control soil moisture

[摘要] Heavy rainfall on sloping ground preceded by prolonged dry period can lead to increased risk of failure of slopes. This can lead to significant impact on infrastructure (both road and rail), which invariably comprises both embankments and cuttings. With global warming, there is an increase in risk of extreme weather and hence likelihood of failure incidents is higher. Capillarity is one of the major water movement mechanisms in soil and thus, there was the need to study the subject. A laboratory based investigation was conducted with the aim of raising water by capillary action and removal of water from the soil surface by the action of wind. The first series of experiments were conducted to investigate the capillary rise of water in soils and more importantly how to improve the height of capillary rise and the volume of water that could be drawn up using capillary action. It included column tests with the base of the soil columns in water and in soil with a range of moisture contents. Final series of tests were conducted to assess the feasibility of using a soil column to draw up water from a free water surface to a higher level where water was removed from the surface by the action of wind with a view to continuously remove water. This involved placing the top of the column in a wind tunnel while the column was stood in water. Overall this study shows that both capillarity and suction created by the wind has the potential to be developed for successful lifting of water. Such a system would not require much energy input, however, it may take longer to lift water at a lesser rate compared to conventional pumping systems.

[发布机构] University:University of Birmingham;Department:School of Engineering, Department of Civil Engineering

[关键词] T Technology;TA Engineering (General). Civil engineering (General)