LI Y K, WANG Z R, HU K,et al.Study on the morphological distribution features of hydraulic fractures considering underground water disaster control[J].Journal of Henan Polytechnic University(Natural Science) ,2023,42(2):34-41.

doi:10.16186/j.cnki.1673-9787.2020100066

Received:2020/10/27

Revised:2021/05/18

Published:2023/03/25

Study on the morphological distribution features of hydraulic fractures considering underground 

water disaster control

LI Yakun, WANG Zhirong, HU Kai, CHEN Lingxia

School of Water Conservancy Engineering，Zhengzhou University，Zhengzhou 450001，Henan，China

Abstract:In order to further explore the penetration features and influencing factors of hydraulic fractures in fractured coal seam，the process of rock fracture was simulated according to the test results of coal and rock in Jiaozuo mining area with RFPA2D finite element software，and the dominant factors of fracture formation were analyzed.The Cohesive element in ABAQUS was adopted to establish the finite element analysis model in consideration of the coupling between the stress field at the crack tip and the primary fracture system in the coal seam according to the geological conditions of the mining area and the mechanical parameters of the coal seam，and the numerical simulation of the fracture extension was carried out.The results showed that there were three basic patterns of fracture extension paths under different geological conditions，namely，directional straight line extension，turning curve extension and secondary turning curve extension.The stress difference at the fracture tip and the development features of primary fractures were the key factors affecting the shape and distribution of hydraulic fractures.In case of small stress difference，the mechanical properties of the primary fracture played a dominant role in the distribution of fracture.With the increase of stress difference，its leading function gradually decreased.In case of excessively small stress difference and excessively weak strength of the primary fracture，it was easy to generate cross and turning at the primary fracture，which was inclined to touch the aquifer and induce various underground water disasters.

Key words:hydraulic fracturing through-crack;RFPA2D software;Cohesive element;fracture extension characteric;numerical simulation

 005_2020100066_李亚坤_H.pdf