Jordan Journal of Civil Engineering

Numerical Analysis Considering the Dynamic Installation Effects of Stone Column on Soft Clay Response

Authors:

Ahmed Nasr; Waseim Azzam; saleh Rashwan;

Abstract:

This study investigates installing stone columns and their influence on the behaviour of soft clay, with a particular focus on both lateral and dynamic changes induced during the installation process, focusing on two distinct installation methods established on Cylindrical Cavity Expansion (CCE) in the Finite Element (FE): a traditional approach and a dynamic installation technique. Stone columns are commonly used to enhance soil properties, including increasing bearing capacity, reducing settlement, and improving overall soil stability. Through (FE) modelling, the research examines the changes in key factors such as lateral stress and soil stiffness, which are key factors in soil reinforcement. In the traditional method, the lateral pressure coefficient K reached values up to 2.25 for the most significant expansion ratio, while the normalized stiffness improved by 2.3 times the initial value. These changes enhanced the bearing capacity within a localized zone of 1 to 3 times the column diameter (r/D), diminishing the effects beyond this range. However, the dynamic method showed even more significant improvements, with K exceeding 3.4 and stiffness reaching over 3.2 times the initial values for the same expansion ratio. This method resulted in a more controlled build-up of lateral stress, extending the bearing capacity improvements to 6 times the column diameter. The results indicate that while both Techniques strengthen the bearing capacity and stabilize the surrounding soil, the dynamic installation technique offers a more pronounced and extended effect, making it a superior choice for capturing the dynamic impact. The study provides valuable insights into stone column installation methods for geotechnical projects requiring dynamic implications.

Keywords:

Finite Element, Dynamic Installation, Plaxis 2d, Soil Stiffness, Stone Column.