ESTIMATED PROBABILITY OF CRITICAL CONDITIONS IN OPERATING OPEN HOLES OF UNDERGROUND GAS STORAGES

Owing to principal different-scale nonuniformity of rock mass, as well as due to economic and technological constraints, the information on the structure and stress state of enclosing rock mass of underground gas storages is always limited and probabilistic. This inevitably affects stability prediction in operating open holes. It is shown that drilling can cause two critical states due to actualization of two failure mechanisms connected with initiation of ring or radial fractures around a hole. It is chosen to study stability of holes with regard to random influences by simulation modeling. By the results of the Monte Carlo simulation, the quantitative estimate of the structural safety factor is carried out. Probabilities of stability or failure of a structure are determined. The critical conditions of an open hole with or without water-saturated beds present in the hole section are analyzed. The influence of random factors on the occurrence of the critical state and safety of the open hole is estimated. The stability probabilities in the open hole are determined at different relative densities of drill mud.


For citation: Khloptsov DG. Estimated probability of critical conditions in operating open holes of underground gas storages. MIAB. Mining Inf. Anal. Bull. 2019;(10):172-182. [In Russ]. DOI: 10.25018/0236-1493-2019-10-0-172-182.

Keywords

Operating hole, open hole, stability probability, drill mud density, rock pressure.

Issue number: 10
Year: 2019
ISBN: 0236-1493
UDK: 622.24 (622.28)
DOI: 10.25018/0236-1493-2019-10-0-172-182
Authors: Khloptsov D. G.

About authors: D.G. Khloptsov, Graduate Student, e-mail: dkhloptsov@gmail.com, National University of Science and Technology «MISiS», 119049, Moscow, Russia.

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