The College of Engineering at the University of Baghdad witnessed the public discussion of the Doctor’s student (Shahad Duja Ali) from the Civil Engineering Department on her thesis entitled (Simulation of Leaching Behavior and Durability of Gypseous Soil Treated with Nano Materials) on Tuesday, 26/12/2024, in Dr. Khaled Shaker Hall. Under the supervision of (Prof. Dr. Mahdi O. Karkush).
The research aims to study the engineering properties of gypsum soil obtained from the Badra District in Wasit Governorate. Two types of nanomaterials (nano-silica and nano-clay) were used at ratios ranging between (1-5) % to improve the dissolution and durability of gypsum soil. The dissolution behavior of gypsum soil was studied using a locally manufactured physical model, and its durability study was based on the progress of the study of the effect of aging, wetting and drying cycles, and freezing and thawing cycles. The effect of nanomaterials on the internal structure of gypsum soil was also studied based on EDX and Fe-SEM tests.
The results showed that using nanomaterials improves the collapse of gypsum soil by a percentage of up to 49% when using Nano-silica and by a percentage of up to 54% when using Nano-clay. The study also showed that the solubility of gypsum soil decreases with increasing the percentage of nanomaterials used and that Nano-cay has the greatest ability to improve the properties of gypsum soil as it led to reducing the subsidence resulting from gypsum dissolution by percentages ranging from 15% to 63% while using Nano-silica led to reducing the subsidence by percentages ranging from 11% to 48%.
Accordingly, the research came out with a set of recommendations, including
- Studying the effect of nanomaterials on the geotechnical properties of soil at different percentages.
- Study the effect of nanomaterials on the internal structure of soil.
- Study the durability of gypsum soil before and after improvement.
- Study the dissolution behavior of gypsum soil before and after the treatment process using nanomaterials.
After scientific discussion by the respected members of the discussion committee and listening to the researcher’s defense, the researcher obtained a PhD in civil engineering/soil mechanics and foundation engineering with a grade of (Excellent).