Source: Untar Public Relations – VA

“Retaining walls are not merely structures, but essential foundations that maintain slope stability to prevent landslides and ensure safety for public use.”

This statement became the central idea in Karminto’s dissertation titled “Development of Collar Cross and Fish Fin Stud Models in Mechanically Stabilized Earth Walls on Red Soil Layers.”

The open dissertation defense was held on Monday (8/9/2025) at the Untar Auditorium, Campus I Untar, and was chaired directly by Untar Rector, Prof. Dr. Amad Sudiro, S.H., M.H., M.Kn., M.M. The session also featured Principal Supervisor Prof. Ir. Roesdiman Soegiarso, M.Sc., Ph.D., Co-Supervisor Dr. techn. Indra Noer Hamdan, S.T., M.T., and an Examination Committee chaired by Ir. Harto Tanujaya, S.T., M.T., Ph.D.

In his research, Karminto—an employee at Structural Precast Concrete Indonesia, Jakarta—developed collar cross and fish fin stud models in Mechanically Stabilized Earth (MSE) walls. The study examined the effects of length, spacing, and backfill soil quality, particularly red soil, on structural stability. The experiments included comparisons with Ovesen and Stromann theories, finite element modeling using PLAXIS 3D, and direct pull-out tests in the field at Geger Kalong Road, Bandung.

The results showed that the innovative model not only improved anchor tensile strength but also met the Indonesian Geotechnical Standard SNI 8460:2017 in terms of deformation, safety factor, overturning moment, sliding moment, and bearing capacity. These findings have strong potential for wide application, including bridge abutments, landslide retaining structures, and retaining walls.

Ir. Harto, as a Chair of the Examination Committee expressed appreciation for Karminto’s research.

“This study makes a real contribution to the field of geotechnics, particularly in efforts to ensure infrastructure safety. We hope these findings can be more widely applied and become a reference for construction development in Indonesia,” he stated.

The session marked Karminto’s successful defense before the examination committee, while also enriching scientific knowledge in civil engineering. Through this research, Karminto emphasized the importance of innovation that prioritizes safety and infrastructure sustainability. Untar continues to be committed to supporting high-quality research that delivers tangible benefits for national development.

(VA/YS)