Geotechnical Risks of Foundation in Karst : A Case Study of Wind Power Plant Podveležje, BiH

Summary

Abstract

The foundation of structures in rock massif seems to be less problematic than foundation in soil, given that rock massif is characterized by significantly better physical and mechanical properties compared to soil. However, cases of foundations in karst also carry certain difficulties that we face during the construction of various infrastructural and energy objects. The karstified limestone massif abounds in numerous underground karst formations such as pits, caves and caverns that can remain hidden and unexplored in the process of geological-geotechnical investigation work and as such represent a significant geotechnical risk. This paper will analyze the case of the foundationing in the karst of the wind turbine poles at the Wind Power Plant Podveležje, Bosnia and Herzegovina. On this project, during the execution of investigations, but also during the excavation of the foundation-rock interface, caverns were identified on the foundation-rock interface and in the rock below the foundation. The paper describes the procedures for detecting such karst formations on and below foundation-rock interface, both during the investigation phase and during the excavation phase, procedures for defining cavern contours, and methods for remediating caverns.