1. School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo　 454000,China; 2. The Collaborative Innovation Center of Coal Safety Production of Henan Province,Jiaozuo　 454000,China; 3. Institute of Resource and Environment,Henan Polytechnic University,Jiaozuo　 454000,China

在实验室通过自制可变初始侧压作用下煤岩压实承载实验装置配合刚性试验机,对4组12个碎石试件进行了4种不同初始侧压作用下破碎岩石压缩承载试验,分析了初始侧压作用下碎石压缩的轴向应力-应变特征,确定了初始侧压与碎石的变形、压实关系,研究了变化侧压与不同初始侧压下碎石轴向应变发展规律。结果表明:初始侧压越大,碎石应力-应变曲线上挠趋势越明显,且曲线越趋光滑,表明碎石颗粒间空隙越小、棱角越趋圆钝及碎石承载载荷越大;随着初始侧压增加,碎石轴向应变与横向应变呈加速减小趋势,不同初始侧压下轴向应变比与横向应变比分别是1.74∶1.65∶1.39∶1与2.51∶2.23∶1.72∶1;碎石初始侧压越大,碎石压实系数越小,碎石初始侧压与压实系数关系可用二次多项式表征;随着轴向应变增加,变化侧压呈增加趋势,初始侧压越大,曲线斜率越小,轴向应变与变化侧压呈线性正相关;初始侧压越大,碎石变化侧压越小,且初始侧压与变化侧压仍可采用二次多项式表征,合理初始侧压有利于碎石承载稳定。

Through rigid testing machine combined with coal-rock compaction bearing device made by ourselves in ini- tial variable lateral pressure,a compression bearing test was operated on four groups of twelve broken rock specimens in different initial lateral pressures. The axial stress-strain characteristics of broken rock in initial lateral pressure were analyzed,the relationships between initial lateral pressure and broken rock deformation,compaction,were determined, and the axial strain laws of broken rock were respectively studied in variable lateral pressure and in different initial one. The results showed that the larger the initial lateral pressure was,the more obvious the stress-strain curve deflec- tion of broken rock was,and the more smoothness of the stress-strain curve,the smaller the gap between the gravel par- ticles was,the blunter the angle was,the larger the load on broken rock was. Axial broken-rock strain and transverse one decreased with initial lateral pressure increase,axial strain rate and transverse one were respectively 1. 74 ∶ 1. 65 ∶ 1. 39 ∶ 1 and 2. 51 ∶ 2. 23 ∶ 1. 72 ∶ 1 in four different initial lateral pressures. The larger the initial lateral pressure on broken rock was,the less the compaction coefficient was,and quadratic polynomial can represent the relationship between initial lateral pressure on broken rock and compaction coefficient. Variable lateral pressure increased with axi- al strain increase,the larger initial lateral pressure was,the less the curve slope was,and axial strain and variable later- al pressure showed linear positive correlation. The larger the initial lateral pressure was,the less the variable lateral pressure on broken rock were,quadratic polynomial can represent the relationship between initial lateral pressure and variable lateral pressure,and the reasonable initial lateral pressure was benefited to broken rock bearing stability.

XIN Yajun,HAO Haichun,LÜ Xin,et al. Compaction characteristics test of broken rock in initial lateral pressure[ J]. Journal of China Coal Society,2018,43(2):457-465.