Influence of Nano-TiO₂ Additives on the Swelling Behavior of Expansive Soils

Expansive soils, rich in clay minerals, undergo significant swelling and shrinkage with moisture changes, often damaging foundations and infrastructure. To mitigate these challenges, ground improvement is essential, commonly achieved through chemical or physical stabilization methods. Nanomaterials have recently emerged as promising stabilizing agents in geotechnical engineering. Their use bridges civil engineering, material science, and nanotechnology. Incorporating nanomaterials to reduce soil swelling is gaining attention as an innovative improvement technique. This study presents an experimental investigation into the effect of Titanium dioxide (TiO2) on the swelling behavior of expansive soil. TiO2 were added at three different dosages (0.5%, 1.0%, and 1.5%) by dry weight of soil. The swelling characteristics of the natural expansive soil were first evaluated in its untreated condition, followed by an assessment of the influence of TiO2 through a series of one-dimensional odometer swell tests. Swelling tests were conducted under a range of vertical pressures (50, 75, 100, 200, and 400 kPa) to quantify the changes in swell percentages and swelling pressure due to TiO2 treatment. The results contribute to a better understanding of the potential of nanomaterials, particularly TiO2, in mitigating the adverse effects of expansive soils in geotechnical applications.