【作者】 韩冰； 王芝银；

【Author】 Han Bing~(1)) Wang Zhiyin~(2)) 1) Petro China Pipeline R& D Center,Hebei 065000 2 ) Beijing Key Laboratory of Urban Oil and Gas Distribution Technology in China University of Petroleum,Beijing 102249

【机构】 中国石油管道研究中心； 中国石油大学城市油气输配技术北京市重点实验室；

【摘要】 基于室内岩石蠕变试验资料确定合理的流变本构模型,对流变参数进行估计,是研究岩石流变力学特性的重要手段。以往的岩石单轴或三轴压缩蠕变试验多采用分级加载方式,为研究卸荷应力状态对岩石流变参数估计结果的影响,本文采用RLW-2000岩石三轴蠕变试验机,对某地区花岗岩分别进行了分级加载和逐级卸载两种不同应力路径条件下的三轴压缩蠕变试验。研究结果表明:应力路径不同,所获取的岩石流变参数也各不相同,通过加载方法获取的瞬时弹性模量和粘性系数的均值要高于卸载条件下相应参数的均值,而粘弹性模量普遍偏低;各项参数的变化趋势随应力水平的增加或减小具有较大差异。更多还原

【Abstract】 It is an important method for studying the rheological characteristic of rock to choose an appropriate rheological model and obtaining the corresponding parameters based on the creep experiment of rock in lab.The step load method is adopted chiefly in the past uniaxial or triaxial compress creep experiment of rock.In this paper, the step load and unload methods are both applied to the creep experiments for granite specimens from some places with the RLW-2000 servo-controlling creep testing machine in order to study the distinction of the rheological parameters estimation between load and unload conditions.The results indicate that the obtained rheological parameters of rock are different if the stress paths are diverse,the elastic modulus and viscous coefficient obtained with the method of step load are usually bigger than the ones by using step unload,and the viscoelastic modulus obtained with the former is smaller than the one with the latter-,the variation rules of every parameter with the increment or decrement of stress levels show a bigger difference.更多还原