Bolt fracture mechanism of roadway driven along gob in high street area caused by mining
WANG Ao
YAO Qiangling
LI Xuehua
DU Mao
LIU Yu
CHEN Tian
Abstract：Roof-corner bolt tails fractures largely occurred in coal-side of 32 16 roadway driven along gob in Wanbei Qianyingzi coal mine.In order to investigate the internal mechanism of this phenomenon,distribution area of bolt fracture,plastic zone characteristic and mechanical failure mechanism of bolt tails were analysed and the reason for bolt failure was studied.In accordance with distribution characteristics of stress in 32 16 roadway driven along gob,the period of excavating roadways was divided to three stages,excavating roadways influenced by constant,unstable and stable supporting stress from upper section of roadway.We found bolts fracturing and mine pressure occurring strongly at the unstable area of upper section of roadway.The results show that the increasing plastic area is the main external reason for the rise of tensile stress of bolt tails.The large deformations in excavating process results in movement of steel belt and consequently stress concentration of bolt tails,thereby contributing to the fracture occur of bolt tails.With the development of elastic area on coal-side of 3216 roadway driv en along gob,bolt stress increases continuously and results in old cracks propagation and their failure.
Keywords：roadway driven along gobbolt tailsbolt fracturestress distribution
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 769-775 )