Abstract
3D rock stress measurements by overcoring are hard to perform when extensive core disking occurs. In the worlds longest double tube road tunnel, located in China, SINTEF experienced this difficulty. SINTEF were assigned to measure the rock stress in order to construct special lightning caverns for safety purposes. Large overburden combined with relatively high in-situ horizontal stress made 3D measurements impossible in one out of two locations. By earlier experience, 2D measurements by the Doorstopper method were tried and resulted in success.Publisert i serie: Proceedings and Monographs in Engineering, Water and Earth Sciences