UNCERTAINTY CHARACTERIZATION METHOD OF ROCK MECHANICAL PARAMETERS EXPERIMENTAL RESULTS:A CASE STUDY OF WUTONGGOU FORMATION IN JIMUSAER, CHINA

摘要

Laboratory experiment is one of the most accurate methods to determine rock mechanics parameters. However, due to the complexity of geological conditions, scientific experimental equipment andother problems, the true value of rock mechanics parameters cannot be obtained, and the error is bound to exist. It is of great significance to master the uncertain distribution characteristics and range of rock mechanics parameters for optimizing drilling scheme and guiding construction. Based on the information diffusion theory, this paper establishes the characterization method of the uncertainty of rock mechanics parameters experimental results, and gives the determination method of its probability distribution function and uncertainty range. Taking the Permian Wutonggou formation of Jimusaer shale oil, the first national shale oil exploration and development demonstration area in China, as an example, the probability distribution function and uncertainty range of Jimusaer Wutonggou formation are given. Among them, the elastic modulus is 31.85~48.12 MPa,Poisson's ratiois 0.21~0.28, uniaxial compressive strength is 74.70~86.31 MPa, and drillability grade is 4.79~6.27. Case analysis shows that the uncertainty characterization method of rock mechanics parameters experimental results established in this paper could better describe the distribution characteristics and range of rock mechanics parameters, and the rock mechanics parameters of Wutonggou formation in Jimusaer provide support for the construction in this area.