Abstract
Hydraulic test (HF and HTPF) is one of the most common methods to determine in-situ rock stress. The interpretation of the shut-in pressure to determine the minor principal stress is an important element of this method, and many different methods to interpret shut-in pressure have been studied and developed throughout the years. Each method has its advantages and disadvantages. With more than 50 years of research and development within the rock stress measurement field, especially in HF, SINTEF has established two practical ways of defining shut-in pressure. These methods are independent and termed zero flow and water hammer, which were published in Trinh et al. (2023). This paper presents laboratory tests to demonstrate these two methods. The results are compared with other existing methods within the rock stress measurement field. These two new methods have traditionally been used in hydroelectric power development, different types of tunnel and cavern projects, and also in mineral mining. The methods have not been used in deep petroleum applications such as oil wells or offshore in porous rock types.