摘要
通过一系列砂岩、页岩和辉绿岩室内蠕变试验,获得了不同应力和初始应变状态下岩石蠕变特性。通过误差分析讨论了计算蠕变速率时如何选择时间增量。讨论了复杂加、卸载条件下时间相关蠕变模型的局限性,提出采用不可恢复应变作为内变量来描述复杂条件下岩石蠕变性质,并据此提出了岩石的内变量蠕变模型。试验数据与模型拟合结果对比表明,内变量蠕变模型较好地反映了3种岩石的蠕变行为。此外,还初步讨论了模型在岩石率相关性质研究中的适用性,并利用相关试验数据进行了验证。
A series of laboratory creep tests have been performed on sandstone, shale and dolerite to investigate the creep behavior of rocks subjected to different stresses and at different initial strains. Error analysis has been performed to study how to select time increment for the calculation of creep rate. The applicability of time-dependent creep model in describing the creep behavior under complex conditions is examined. An internal state variable creep model is proposed, in which the irreversible strain is considered as the internal state variable. The fitting of test data into the model shows that the internal state variable creep model is capable of describing the creep behavior of the three rocks in laboratory tests. A primary study of the applicability of the internal state variable model in describing rate dependent behavior of rocks is performed; and test data in literatures are used to verify the applicability.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2012年第12期3529-3537,3603,共10页
Rock and Soil Mechanics
基金
国家自然科学基金资助项目(No.41202205)
中国博士后科学基金特别资助项目(No.2012T50615)
教育部高等学校博士学科点专项科研基金(No.20110131120075)
岩土力学与工程国家重点实验室开放课题(No.Z011004)
关键词
岩石力学
蠕变
本构模型
内变量
不可恢复应变
时间相关
率相关
rock mechanics
creep
constitutive model
internal state variable
irreversible strain
time dependent
rate dependent
