含水状态下硬脆性泥页岩蠕变特性实验研究

对岩石进行不同含水率下三轴蠕变实验,试样在整个加载过程中,经历了衰减蠕变、等速蠕变和加速蠕变三个蠕变阶段。根据不同含水率岩样的等时应力应变曲线,可以看出泥页岩的蠕变是非线性的;并且随含水率和应力水平的提高,应力应变的非线性程度也增大。在相同的外载条件下,随着含水率的增加,泥页岩的蠕变变形增加、蠕变进入稳定阶段所需的时间越长;而岩石长期强度呈减小的趋势。说明对于泥页岩地层的钻井施工,需要考虑泥页岩的时效变形行为及流变效应。

Creep experimental study of brittle shale triaxial state under aqueous

Rock under different water contents were triaxial creep test, the creep specimen consists of three stages, decay creep and steady creep and accelerating creep constant throughout the loading process. According to different moisture content of the sample, such as the stress strain curve, it can be seen that the shale creep is nonlinear,and with increasing moisture content and stress level, non-linear stress-strain level increases. Under the same external load conditions, the shale creep deformation increases with increasing moisture, the longer the time required to enter the steady creep, and long-term strength of rock was a decreasing trend. It illustrates the drilling shale formations should consider the aging deformation behavior and rheological effects.