The Estimation of One-Dimensional Collapse for Highly Gypseous Soils

Abstract

The presence of gypsum in soils has a notable impact on their engineering properties. Since the gypsum dissolved due to water percolation, their properties may change over time. Collapsibility is considered the most significant parameter ruling the characteristics of highly gypseous soils for several decades; standards have tried to find the best formula for expressing the amount of strain in collapsing soils. Starting from the single and double odometer test, coming to the one-dimensional collapse. In this research 21, highly gypseous soil samples were prepared and tested according to three different standards. For different densities, the results indicate that collapse potential values obtained from the single oedometer method are quite similar to those using the double oedometer test under different conditions. Furthermore, the collapse strain estimated by the onedimensional collapse test gives different values due to the variety of applied pressure at wetting under different conditions. Also, the amount of gypsum dissolved during the tests indicates that the expression of the quantum of collapsibility of gypseous soils (strain) is more satisfactory than the qualitative declaration adopted by the version of the old method.

Using a Laboratory Model Test to Assess the Collapsibility of a Gypseous Soil Improved with Geogrid and Cement Kiln Dust

“…They need an open metastable structure or open porous fabric to be developed using various bonding procedures. (Al-Mukhtar and Al-Obaidi, 2022) and (Fattah et al, 2015) and reported that when soils are initially dry, volume changes that lead to collapse frequently happen in non-plastic or extremely low plasticity soils and are quicker than those seen during consolidation processes. Furthermore, inadequate compaction techniques, low moisture levels, and waste items can also cause soil to artificially collapse.…”

Experimental Investigation of Capillary Rise in Unsaturated Gypseous Soils

“…When the gypseous soil is exposed to water, the collapsibility of the soil will be increased. The dissolution of salts inside the soil mass will create new pores inside the soil structure and lose the bonds between the soil particles, leading to the metastable structure [2][3][4][5][6].…”