Title : Soft ground improvement techniques: theoretical, laboratory and field based investigations.
Abstract:
Reducing long-term settlement of infrastructure and providing cost-effective foundations with sufficient load-bearing capacities are national priorities for infrastructure development in most countries. In particular, transport infrastructure built on soft soil can cause excessive settlement initiating undrained failure of super-structure if proper ground improvement is not carried out. Adequate ground improvement techniques can be adopted to prevent unacceptable excessive and differential settlement and increase the bearing capacity of the foundations at much lower cost. Over several decades, various ground improvement techniques have been developed, which include use of admixtures, chemical stabilization, dynamic compaction, preloading with vertical drains and stone column, piling, among others. Each of these techniques has different mechanisms to improve the soft ground. The authors have conducted extensive theoretical and experimental (laboratory and field) investigations on various ground improvement techniques. The theoretical analysis included rigorous numerical studies based on finite difference and finite element modelling. The laboratory model studies involved extensive experimentations using sophisticated test set-ups with reliable control mechanisms. The field-based investigations were conducted in adequate site comprising of soft, compressible soils. In this paper, brief overview of the various investigations conducted has been briefly described. Also, comparative studies on different methodologies have been described and their suitability in different ground conditions have been analysed. A set of case studies has been conducted at selected site locations. Adequate quantifications of the efficiency of the methodology are incorporated and relevant conclusions are drawn.
