Optimization of the Orientation of Large Underground Caverns in High Stress Condition – a case study of 850 Mw ratle Hydro Electric Project, India

Underground caverns are used for a variety of purposes. These include caverns for Desilting, Surges, Turbine, Generators & Transformers, etc. in hydroelectric projects, caverns for storage of liquid or gaseous fuels, underground caverns warehouses and underground sports facilities. Because of the high capital costs and the risks associated with public access to these facilities, care has to be taken in the design of the caverns to ensure that potential risks are kept to an absolute minimum while, at the same time, providing cost effective and practical engineering solutions.

The present paper is a case study from Indian Himalayan area where orientation of the cavities for underground caverns for a mega hydroelectric project has been finalized from a practical point of view with the goal to minimize stress concentration problems, create a stress field as uniformly distributed as possible in the excavation of underground structures with optimum and effective support system.