摘要
通过室内蠕变试验和理论分析,对加锚改善岩石流变力学特性进行了研究,并探讨了锚固控制岩石流变的力学机制。采用RLJW-2000型流变试验机,对红砂岩及其加锚试件进行分级加载(100 h以上)单轴压缩试验,结果表明,加锚后岩石的流变应力阀值提高了20%～30%c,且不同应力水平流变量均能得到一定控制,加锚使试件的长期强度增加了5%～10%c。此外,基于整体协调变形原理,建立了加锚体流变本构方程,推导出了一维B-K模型解答,算例分析表明,锚杆密度越大,对岩石流变控制效果越好,得出锚杆等效刚度是约束岩石流变的主导因素,但从技术经济角度考虑,锚杆支护密度与岩石流变参数之间存在一个合理的匹配区间。研究结果对长期使用的岩体工程锚固支护设计提供了理论依据。
By laboratory test and theoretical analysis,the rheological properties of anchored rock and controlling mechanism by anchor are studied.The results show that,non-anchored and anchored specimens’ indoor long-time（above 100 h） creep test is done by RLJW-2000 rheology tester;creep stress threshold of anchored rock is increased by about 30% c;creep deformations at different stress level stages are significantly controlled;and anchored specimen’s long-term intensity is increased by 5% to 10% c.In addition,according to the equivalent co-deformation principle,one-dimensional creep constitutive equation of anchored rock is established;the answer of anchored generalized Kelvin（B-K） model is derived.The example shows that rock rheology’s control effect gets better with increasing of bolt consistency,which can be obtained that the anchor’s equivalent stiffness is a dominant factor restraining rock rheology.But from the view of economic technology,bolt consistency and rock rheological parameters have a rational matching interval.The result provides a theoretical basis for the anchorage support design of rock engineering after long-term service.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2012年第6期1730-1734,共5页
Rock and Soil Mechanics
基金
国家自然科学基金(No.51004068)
山东省优秀中青年科学家科研奖励基金(No.BS2011NJ014)
煤炭资源与安全开采国家重点实验室开放基金项目(No.SKLCRSM10KFB03)
关键词
加锚岩石
流变特性
本构模型
锚固机制
anchored rock
rheological property
constitutive model
anchoring mechanism
