A study on electrokinetic stabilization of soft Bangkok clay using a physical model

Department of Civil Engineering, School of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bangkok, Thailand

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

Soft Bangkok clay, extensively distributed within Thailand’s Chao Phraya Basin, presents significant geotechnical challenges due to its low shear strength, high compressibility, and considerable long-term settlement. Conventional ground improvement techniques commonly used in Thailand, such as preloading with surcharge, prefabricated vertical drains (PVDs), and vacuum consolidation with PVDs, have proven effective in many applications. However, the application of electrokinetic stabilization remains limited in practical engineering projects within the country. This study investigates the potential for electrokinetic stabilization to enhance the engineering properties of soft Bangkok clay, focusing on improvements in shear strength, compressibility, and long-term settlement, as well as assessing its environmental impacts. The research examines the fundamental mechanisms involved electroosmosis, electrolysis, electrophoresis, and electromigration through small-scale physical modeling and conventional laboratory testing. The methodology includes developing a small-scale physical model and evaluating both basic and mechanical properties of soil samples before and after electrokinetic stabilization. The experimental program involves determining initial properties such as water content, Atterberg limits, pH, unit weight, specific gravity, compressibility using the oedometer test, and shear strength using the unconfined compression test. During the electrokinetic process, settlement, drained water volume, electrical current, voltage, pH variation, and surface cracking are continuously monitored. The findings aim to demonstrate electrokinetic stabilization as an effective alternative for ground improvement in confined urban areas where conventional methods are impractical, thereby contributing to safer construction and more efficient land utilization in Bangkok soft clay regions.