Mechanical properties and acoustic emission characteristics of thick hard roof sandstone in Shendong coal field
Huigui Li
Huamin Li
摘要：The mechanical properties and acoustic emission characteristics of thick hard roof sandstone were investigated.Samples were taken from the 30.87-m thick sandstone roof in a mine in the Shengdong coal field,China.Firstly,the composition and microscopic characteristics were analyzed by XRD and FE-SEM,respectively.Moreover,the indirect tensile test,uniaxial compression test,three axis compression experiment and AE test are carried out by using RMT-150C mechanics experiment system with DS5-8B AE test system.The experiment results indicate that the main framework particles of sandstone are quartz and feldspar,and mainly quartz.Cements are mainly pyrite,kaolinite,chlorite and zeolite cross needle,clinochlore,and clay minerals.The microstructure of sandstone is very dense,with few pores and high cementation degree.The tensile strength,compressive strength and elastic modulus of sandstone are 4.825,85.313 MPa,13.814 GPa,respectively,so the sandstone belongs to hard rock.The AE cumulative counts of sandstone can be divided into three phases:relatively fiat growth period,rapid growth period and spurt period.The signal strength of AE waveform can be used as a warning signal.In the tensile fracture zone,the warning value is 0.4 mV,and in the compression shear failure zone,it is 4 mV.The numbers of cumulative counts of AE under different stress conditions have obvious difference.Moreover,the growth of cumulative counts of acoustic emission is more obvious when the stress is more than 60％ of the peak stress.
机标关键词：acoustic emissionmechanical propertiestensile strengthcompression testshear failurefracture zoneclay mineralstensile test
资助基金：This research is funded by the Chinese Natural Science Committee under Grant (No.U1261207)
论文发表日期：2017-01-01
在线出版日期：2025-08-15（本平台首次上网日期，不代表文献的发表时间）
页数：12( 147-158 )
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