Large-scale apparatus for measurement of collapse potential of soils with simulating the pattern of water infiltration ability

Collapsible soil as an example of problematic soils can cause problems in structures. Collapsible soil may be stable before the presence of water, but after water enters, it experiences significant and sudden settlement. The most important issue in dealing with these soils is to predict their settlement. Up to now, various experiments have been designed in the laboratory or in-situ to determine the collapse potential, the most common of which is the oedometer test. The most important drawback of the existing experiments is the impossibility of simulating the pattern of water infiltration in the soil. In this study, an apparatus with a mold with a diameter of 14 cm and a height of 10 cm was built that has the ability to simulate water infiltration patterns and can measure the amount of collapse potential based on the source of water infiltration. This apparatus simulates water infiltration patterns into four categories based on the direction of water movement (from top to bottom or from bottom to top) and water distribution (point or expanding). The laboratory results of this apparatus on a sample of collapsible soil show that the collapse potential depends on the water infiltration pattern and it isn’t possible to use one collapse potential amount for all patterns. According to the laboratory results, the highest collapse potential is related to the pattern of water infiltration from top to bottom and expanding form, and the lowest is related to the pattern of water infiltration from bottom to top and point form.