刘德克;李克钢
【摘 要】为了探讨内聚力C和内摩擦角φ对岩样峰值强度的影响规律，采用数值模拟手段，获取岩样轴向应力、轴向位移、峰值强度随C、φ值逐渐下降的变化规律。研究结果表明：内聚力C和内摩擦角φ数值的降低，均会导致应力位移曲线峰后平缓；当内摩擦角φ值降低40％时，峰值强度降低39．5％，峰值强度阶段降幅最大值为10．53％，峰值强度随次数的增加向一极值发展，且峰值强度阶段降幅有减小趋势；而当内聚力C值减小40％时，峰值强度降低29．82％，阶段降幅最大值7．98％；对比说明内摩擦角φ对峰值强度的影响程度要比内聚力C更大。%In order to study influence of cohesion and internal frictional angle on the peak strength of rock sample , the change rules of axial stress , axial displacement and peak strength with the de-cline of C and φwere obtained by means of numerical simulation .The results showed that the de-clined cohesion and internal frictional angle would cause stress -displacement curve after the peak smooth.When internal frictional angle value was reduced by 40% and the peak strength was de-creased by 39 .5%, the maximum value of decline of
peak strength stage was 10 .53%, the peak strength approached an extreme value with increased times and the decline of peak strength stage had a decreasing trend .When the cohesion value was reduced by 40%, peak strength was de-creased by 29.82%, the maximum value of decline of peak strength stage was 7.98%.Making a comparison of the data , the influence degree of internal frictional angle on the peak intensity was greater.
【期刊名称】《矿产保护与利用》
【年(卷),期】2015(000)003
人间 李锐【总页数】4页(P16-19)
【关键词】变化规律;峰值强度;内聚力;内摩擦角
【作 者】刘德克;李克钢
【作者单位】昆明理工大学国土资源工程学院，云南昆明，650000;昆明理工大学国土资源工程学院，云南昆明，650000
【正文语种】中 文
【中图分类】TU458+.4
内聚力和内摩擦角对岩样峰值强度影响规律探讨*
刘德克，李克钢
(昆明理工大学国土资源工程学院，云南昆明，650000)
*收稿日期:2015－04－23
基金项目:国家自然科学基金( 41202229，41362013)新华月报
作者简介:刘德克( 1990－)，男，硕士研究生。
摘 要:为了探讨内聚力C和内摩擦角φ对岩样峰值强度的影响规律，采用数值模拟手段，获取岩样轴向应力、轴向位移、峰值强度随C、φ值逐渐下降的变化规律。研究结果表明:内聚力C和内摩擦角φ数值的降低，均会导致应力位移曲线峰后平缓;当内摩擦角φ值降低40
%时，峰值强度降低39．5%，峰值强度阶段降幅最大值为10．53%，峰值强度随次数的增加向一极值发展，且峰值强度阶段降幅有减小趋势;而当内聚力C值减小40%时，峰值强度降低29．82%，阶段降幅最大值7．98%;对比说明内摩擦角φ对峰值强度的影响程度要比内聚力C更大。
关键词:变化规律;峰值强度;内聚力;内摩擦角
中图分类号: TU 458
市场需求 +．4
文献标识码: B
文章编号:1001－0076( 2015) 03－0016－04
氯化钠晶体DOI:10．13779/j．cnki．issn1001－0076．2015．03．004
The Discussion on Effect of Cohesion and Internal Frictional Angle on the Peak Strength of Rock
LIU Deke，LI Kegang
维尔斯特 ( Shool of Land Resources Engineering，Kunming University of Science and Technology，Kunming 650000，Yunnan，China)
Abstract: In order to study influence of cohesion and internal frictional angle on the peak strength of rock sample，the change rules of axial stress，axial displacement and peak strength with the decline of C and φ were obtained by means of numerical simulation．The results showed that the declined cohesion and internal frictional angle would cause stress－displacement curve after the peak smooth．When internal frictional angle value was reduced by 40% and the peak strength was decreased by 39．5%，the maximum value of decline of peak strength stage was 10．53%，the peak strength approached an
extreme value with increased times and the decline of peak strength stage had a decreasing trend．When the cohesion value was reduced by 40%，peak strength was decreased by 29．82%，the maximum value of decline of peak strength stage was 7．98%．Making a comparison of the data，the influence degree of internal frictional angle on the peak intensity was greater．
Key words: change rules; peak strength; cohesion; internal frictional angle
1 引言
内聚力C和内摩擦角φ是两个影响岩石强度的重要力学参数，从以往前人的试验结果和理论分析来看，岩石的内聚力和内摩擦角越高，岩石的强度越高，即内聚力和内摩擦角将影响岩石应力应变曲线的峰值强度
［1－2］，但是，内聚力和内摩擦角对岩石峰值强度的“贡献度”到底遵循一个什么样的关系，还不是十分清楚，这是因为在试验中，很多岩样的内聚力和内摩擦角是不同的，除此之外，我们也不能保证其他(弹性或塑性)本构力学参数完全相同。鉴于从试验的
角度研究内聚力和内摩擦角对岩石峰值强度的影响规律十分困难，因此进行一定的数值计算是十分必要的，随着计算机技术的发展，数值模拟技术愈发强大，这使得数值模拟计算逐渐成为解决岩土工程问题的一种重要手段
［3］。
青鸟网
王学滨等
［4－5］采用了拉格朗日元法( FLAC)已经比较深入地研究了岩样尺寸、围压、端面约束对岩样剪切带倾角、塑性区、位移场以及侧向变形的影响;文献
［6］通过FLAC模拟指出，随着初始内聚力和内摩擦角的增加，岩样破坏模式由复杂向简单剪切破坏转变，发生破坏的单元数目降低，剪切带倾角增大;文献
［7］采用FLAC模拟初始内聚力及内摩擦角对具有随机材料缺陷单轴平面应变压缩岩样破坏过程及声发射的影响，指出岩样达到应力峰值后，破坏的单元数增长不大，声
发射数显著增加的三个区段均位于峰前，声发射数的增加源于缺陷的长大，聚结和传播;柯长仁等
［8］对不同围压下岩石破坏全过程进行了数值模拟，利用最小二乘法的线性拟合，得出了岩石强度随围压变化的表达式;黄彦华等
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