The creep compaction behavior of crushed mudstones under the step loading in underground mining
Zhibiao Guo
Qiong Wang
Songyang Yin
Xiaohui Kuai
Dongshan Yan
Mengyi Li
Yandong Qu
摘要：The crushed rocks are used as a filling material in mined-out areas of underground mining.Compared with the man-made filling materials,the crushed rocks exhibit higher compressibility and lower stability,which may result in instability of surrounding rock and surface subsidence.To study the creep compaction behavior of crushed mudstones,a series of creep tests are conducted.The investigations show that the creep compaction behavior of crushed mudstones is highly dependent on the original grain composition and axial stress applied on the samples.The samples with more large particles are easier to deform at initial loading stage for more large voids existed in the samples,and exhibit greater stability than those with smaller particles when the axial stress less than the bearing capacity of "framework structure".When the axial stress is higher than 20 MPa,the influences of grain composition on deformability of crushed mudstones are weakened after the samples experience repeated compression.At lower stress level,the creep behavior prefers to occur in the samples with smaller particles,which is mainly caused by particles flow without significant particle breakage.As the axial stress increases,the single-sized sample with smaller particle size and the well-graded sample with larger Talbol power exponent n present more unstable under the constant stress.In addition,the filling of the residual intergranular voids by small particles formed by crushing and splitting behavior is the main cause of creep deformation.Lastly,a creep equation of crushed mudstones is obtained in this paper,which can agree with the experimental results in good.
机标关键词：
资助基金：This research was supported by the National Natural Science Foundation of China(Grant 51479195)the National Key Research and Development Plan of China(2016YFC0600901)the Special Fund of Basic Research and Operating of China University of Mining and Technology,Beijing(Grant 2009QL06)
论文发表日期：2019-01-01
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：11( 408-418 )
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