采矿与安全工程学报2017，Vol.34Issue(1)：148-154,7.DOI:10.13545/j.cnki.jmse.2017.01.023
基于函数阶微积分的泥岩高温蠕变特性分析
Analyzing creeping properties of mudstone at high temperature based on variable-order fractional calculus
摘要
Abstract
Respective tests were carried out on mudstone at 25 ℃ and 700 ℃ for its creeping prop-erties with electric-hydraulic servo material testing system MTS810 and its assorted high-temperature electric stove.The creeping constitutive model of mudstone was established based on variable-order calculus and the influence rule of stress and temperature on the creeping properties of mudstone was determined through the comparison of model numbers.Testing results from material composition and mesoscopic structures of mudstone explained the reasons for change of the variable-order function and further illustrated the creeping properties of mudstone changing mechanism.The results have shown that the middle order of the mudstone creeping model is divided into three stages as time passes,which matches the three stages of creeping deformation of mudstone;the order increases with the stress level in the same stage,which means viscidity is supposed to be larger during the creep creeping deformation at 700 ℃ can be divided into three stages:decelerating creeping,steady-state creeping and constant creeping.Three stages divided by order-time curve properly matches stages divided by the creeping curve.What's more,significant stability of the process which cannot be shown at 25 ℃ is demon-strated in the order-time curve at 700 ℃,and more time is needed to start constant creeping at 700 ℃.The order was increased with the stress levels in the same stage,which means viscidity is supposed to be larger during the creep.The second stage which cannot be shown at 25 ℃ lasted longer in the or-der-time curve at 700 ℃,which can explain that high temperature can effectively improve viscosity properties of mudstone.More time is needed to start constant creep at 700 ℃,and the difference in-creased with stress decreased,which means high temperature under low stress level can improve viscos-ity properties in the process of transient creep.The presence of illite under 700 ℃ and thermal expan-sion effect which makes mudstone's internal mesoscopic structure denser are the fundamental reasons for mechanical properties of mudstone.关键词
高温蠕变/函数阶微积分/本构模型/力学特性Key words
high-temperature creep/variable calculus/constitutive model/mechanical properties分类
矿业与冶金引用本文复制引用
曹丽丽,浦海,仇陪涛,张连英..基于函数阶微积分的泥岩高温蠕变特性分析[J].采矿与安全工程学报,2017,34(1):148-154,7.基金项目
国家重点基础研究发展计划(973)项目(2015CB251601,2013CB227900) （973）
国家自然科学基金项目(51322401,51421003,U1261201) （51322401,51421003,U1261201）
中央高校基本科研业务费专项资金项目(2014YC09,2014ZDPY08) （2014YC09,2014ZDPY08）
高等学校学科创新引智计划项目(B07028) （B07028）
江苏省研究生创新基金项目(KYLX_1371) （KYLX_1371）
江苏省“333工程”科研项目(BRA2015065) （BRA2015065）
