15.06.2026

2025 BGA Medal Winning Paper announced

The British Geotechnical Association (BGA) is pleased to announce that the 2024 BGA Medal has been awarded to Sonu Kumar, Ashutosh Kumar, Tiago A.V. Gaspar and Ashraf S. Osman, for their paper “Impact of Suction and Swell-Induced Softening on Pile Behaviour in an Unsaturated Expansive Clay” published in ASCE in 2025.

2025 BGA Medal Winning Paper announced

The British Geotechnical Association (BGA) is pleased to announce that the 2025 BGA Medal has been awarded to Sonu Kumar, Ashutosh Kumar, Tiago A.V. Gaspar and Ashraf S. Osman, for their paper “Impact of Suction and Swell-Induced Softening on Pile Behaviour in an Unsaturated Expansive Clay” published in ASCE in 2025.

Fourteen entries were received for the award this year, all of which of a very high standard, leaving the judging panel with a very challenging task in selecting the winner.

The judges agreed that the winning paper presents an important and complex problem in unsaturated expansive clays, combining centrifuge testing with advanced 3D coupled FE modelling in a coherent framework. Tested in an instrumented field, the study provides compelling observations offering crucial insights on landslide mechanisms. The ability to capture key mechanisms such as suction loss, swell-induced softening, and their impact on pile behaviour is a clear strength of this work.

The BGA Medal is awarded annually (each calendar year) by the BGA to a paper substantially authored by a BGA member or BGA members published in an international journal or from BGA, ISSMGE and ISRM conferences, and submitted for consideration of the award.

More from BGA

  • Become a member

    Find out more about the benefits of becoming a member of the BGA.

    More Info
  • The Rankine Lecture

    Widely viewed as the most prestigious of the invited lectures in geotechnics and was first held in 1961.

    View Event