(February 2025) In this webinar, we will explore the updated Swelling Rock constitutive model in PLAXIS, focusing on its application to the challenging task of simulating the stress- and time-dependent behaviour of swelling rocks. Swelling rocks, such as claystones and anhydrite-bearing formations, present significant challenges in tunnelling and infrastructure design due to their complex deformation behaviour in the presence or infiltration of water. With the introduction of new formulations, now referred to as the MAS and MAS-Logt models, we address different swelling mechanisms to provide more accurate predictions.

Using real-world examples, we will demonstrate how these models can aid in predicting swelling pressures and deformations, enabling reliable design checks for tunnel support structures.

Learning Points:

  • Understanding the key mechanisms driving swelling behaviour in clay and anhydrite rocks, including the differences captured by the MAS and MAS-Logt models.
  • Calibrating the Swelling Rock model using laboratory test data and highlighting the influence of key input parameters on model behaviour.
  • Applying the model to practical cases to predict swelling pressures, invert heave and the time-dependent evolution of swelling.