Laboratory simulation of the influence of groundwater rise and drip irrigation on the settlement of a sample of collapsible desert soil

Most types of sand have low susceptibility to settlement when in dry, dense and well-graded states but certain sands, when saturated, exhibit a decrease in suction and tensile strength hence leading to a sudden decrease in volume. Such sands are known as collapsible soils and require special consideration because their behaviour cannot be assessed using conventional settlement analysis methods. Irrigated landscapes overlying collapsible strata have caused settlement problems and infrastructure damage in Abu Dhabi area. Using borehole samples from the area, the present work simulates the settlement response of the collapsible sand when sandwiched between two other layers inside a metal mould and loaded with a constant surcharge pressure while varying water infiltration rates and static water levels. The primary goal of the research is to develop relationships for estimating settlement due to collapsible strata by taking into account layer thicknesses, groundwater table and irrigation intensity and duration.