基于微米压痕试验的分数阶蠕变模型

Fractional Order Creep Model Based on Micro-indentation Test

为了研究干热岩热储层岩石长期力学性能,通过网格化微米压痕蠕变试验方法研究了花岗岩时间相关细观力学变形。结果表明:在恒定载荷作用下,花岗岩压痕点均表现出明显的蠕变变形;串联弹簧元件和Abel黏壶组成的分数阶Maxwell模型,较好地描述了花岗岩在压头恒定载荷下的时间相关变形;通过网格化微米压痕试验拟合得到的细观力学参数与花岗岩成分及宏观力学参数之间的关系尚不明确,有待进一步研究。同时,作为一种新型的岩石细观力学特性定量评价方法,微米压痕测试技术在岩石力学参数测试上表现出良好的应用前景。

In order to study the long-term mechanical properties of dry hot rocks in thermal reservoir,the time-dependent micromechanical deformation of granite was studied by grid micro-indentation creep test.The results show that the indentation points of granite show obvious creep deformation under constant load.The fractional Maxwell model composed of spring elements and Abel pot in series can describe the time-dependent deformation of granite under constant pressure.The relationship between the micromechanical parameters obtained by grid micro-indentation test and the composition and macro mechanical parameters of granite is not clear,which needs further study.At the same time,as a new quantitative evaluation method of rock micromechanical properties,micro-indentation test technology has a good application prospect in rock mechanical parameters assessment.