基于DSCM的岩石蠕变变形场演化试验研究  

Experimental study on the evolution of creep deformation field of rock based on DSCM

作　　者：宋义敏[1] 赵同彬[2,3] 姜耀东[2] 

机构地区：[1]北方工业大学建筑工程学院,北京100144 [2]中国矿业大学(北京)力学与建筑工程学院,北京100083 [3]山东科技大学资源与环境工程学院,山东青岛255590

出　　处：《中国矿业大学学报》2013年第3期466-470,共5页Journal of China University of Mining & Technology

基　　金：国家重点基础研究发展计划(973)项目(2010CB226801);国家自然科学基金项目(51004068)

摘　　要：采用分级加载方式对一种红砂岩试件进行单轴压缩蠕变试验,通过Charge-Coupled De-vice(CCD)相机采集加载全过程的试件表面散斑图像,以白光数字散斑相关方法(DSCM)对分级加载不同阶段试件表面变形场演化及裂隙位移演化进行观测和分析.结果表明:在分级加载过程中,试件的瞬时变形量随着载荷的增加而减小,蠕变变形量随着载荷的增加而增加;低应力水平,试件处于均匀变形状态,不发生蠕变或蠕变量较小;中等应力水平,裂隙产生及裂隙在整个恒载期间未发生蠕变扩展的变形累积阶段;高应力水平,裂隙在恒载初期的变形累积到恒载后期的裂隙稳定蠕变扩展,最终加速蠕变扩展;当岩石试件变形出现裂隙区域后,裂隙的位移错动和位移拉伸直接影响了岩石蠕变位移特征.裂隙的位移错动速率包括减速错动、稳定错动和加速错动3种形式.Using the grading loading way is to carry out the creep experiment of uniaxial compression on red sandstone.The surface speckle images of specimen are recorded by Charge-Coupled Device（CCD） camera,and using digital speckle correlation methods（DSCM） is to observe and analyze the evolutions of deformation field and fracture displacement of specimen surfaces which are in different grading loading stages.The results show that： in the process of grading loading,the instantaneous deformation of specimen decreases as the loading increases,and the creep deformation increases with the increases of loading;under the condition of low stress,no or small amount of deformation occurs when the specimens stay at the uniform deformation state;under the condition of medium stress,fractures occur and fractures don＇t extend when the loading is constant;under the condition of high stress,fractures deformation in the initial stage accumulate,and then the deformation stably expands in the next stage,finally accelerating the creep expansion.After the region of fracture appears on rock specimen,the dislocation and stretch of displacement of fractures directly affects the characteristics of creep deformation displacement of rock.The rate of fracture displacement dislocation includes deceleration,stable and acceleration dislocations.

关 键 词：分级加载 蠕变 断裂 数字散斑相关方法 位移场 

分 类 号：TU452[建筑科学—岩土工程]