循环加卸载下黑云母石英片岩的弹性模量与能量演化特征研究  

EVOLUTION CHARACTERISTICS OF ELASTIC MODULUS AND ENERGY OF BIOTITE QUARTZ SCHIST UNDER CYCLIC LOADING AND UNLOADING TEST

作　　者：裴润生 包含[1,4] 兰恒星 黄晓林[3] 晏长根[1] PEI Runsheng;BAO Han;LAN Hengxing;HUANG Xiaolin;YAN Changgen(School of Highway,Chan an University,Xi'an 710064,China;Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China;Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;Xi'an Key Laboratory of Geotechnical Engineering for Green and Intelligent Transport,Xi'an 710064,China)

机构地区：[1]长安大学,公路学院,西安710064 [2]中国科学院地理科学与资源研究所,北京100101 [3]中国科学院地质与地球物理研究所,北京100029 [4]西安市绿色智慧交通岩土工程重点实验室,西安710064

出　　处：《工程地质学报》2024年第1期74-85,共12页Journal of Engineering Geology

基　　金：国家自然科学基金项目(资助号:42177142,42041006);国家重点研发计划项目(资助号:2019YFC1520601);西安市科协青年人才托举计划(资助号:095920201310);长安大学中央高校基本科研业务费专项资金(资助号:300102212213)。

摘　　要：黑云母石英片岩是一种典型的各向异性岩石,为研究其损伤演化规律及各向异性表现特征,针对含0°,45°,90°3种片理角度的试样,开展了等塑性应变循环加卸载试验。结果表明:不同片理面角度试样的破坏模式有所不同,0°片理面试样中的张拉破裂现象与45°片理面中的剪切破坏现象尤为明显。随着塑性应变增加,黑云母石英片岩的弹性模量表现出先强化、后弱化的现象,这一现象在高围压下更为明显。在弱化阶段中,弹性模量演化的转折点与裂纹起裂强度σci稳定时对应塑性应变一致。弹性模量作为岩石损伤劣化过程的评价指标较完整性系数受片理面角度的影响更小。在岩石内部能量演化过程中,耗散能大小与片理面角度的关系为0°>90°>45°,耗散能、弹性能下降的速率大小关系为45°>90°>0°,其降至稳定时与岩石损伤强度σcd稳定时对应塑性应变一致。该研究借助弹性模量和能量演化规律分析,探究了黑云母石英片岩的损伤演化力学行为。The biotite quartz schist is a typical anisotropic rock.To study its damage evolution law and anisotropic characteristics,equal plastic strain cyclic loading and unloading tests were carried out on samples with schistosity angles of 0°,45°,and 90°.The results show that the failure modes of specimens with different schistosity plane angles are distinct,with tension fracture phenomena observed in the 0°schistosity samples and shear fracture phenomena in the 45°schistosity samples being particularly pronounced.With an increase in plastic strain,the elastic modulus of biotite quartz schist first strengthens and then weakens.This phenomenon is more evident under high confining pressure.The turning point in the weakening stage is consistent with the corresponding plastic strain when the initiation strength is stable.As an evaluation index of rock damage and the deterioration process,the elastic modulus is less affected by the angles of schistosity than the integrity coefficient.In the process of the internal energy evolution of rock,the relationship between dissipated energy and the angles of schistosity is 0°>90°>45°.The relationship between the decreasing rate of dissipated energy and elastic energy is 45°>90°>0°.The corresponding plastic strain of the elastic energy and dissipated energy when it evolves to a stable state is the same as that of damaged strength.This study explores the mechanical behavior of damage evolution of biotite quartz schist through the analysis of the evolution characteristics of elastic modulus and energy.

关 键 词：黑云母石英片岩 各向异性 循环加卸载 弹性模量 能量 

分 类 号：TU45[建筑科学—岩土工程]