摘要
采用TAW-2000电液伺服岩石三轴试验仪对海棠山隧道砂岩试样进行了分级加载蠕变试验,基于改进的西原模型建立了描述衰减蠕变与稳定蠕变阶段的变参数蠕变方程,并对蠕变参数的变化规律进行了拟合分析。研究结果表明,试验曲线与模型计算曲线相吻合,试样在低应力状态下的蠕变过程具有明显的衰减蠕变与稳定蠕变阶段,在高应力状态下出现加速蠕变阶段,但最终变形量小于常规三轴极限应变值。基于试验结果拟合出了不同应力状态下不同时刻的蠕变参数及蠕变参数随应力及时间变化的数学表达式,蠕变参数的变化能较好地反映衰减蠕变阶段与稳定蠕变阶段岩石结构的劣化过程,说明了该蠕变方程能较好地模拟砂岩衰减蠕变与稳定蠕变阶段的蠕变特性。
Utilizing the TAW- 2000 electro-hydraulic servo rock 3-triaxial test instrument,the step load creep test on sandstone of Fuxin Haitangshan tunnel is carried out. Based on the improved Nishihara creep model,the variable parameter creep equation for describing the decay and steady creep stages is established,and the variation law of creep parameters is fitted and analyzed. The research result indicates that（ 1） the model calculated curves agrees well with the experimental curves;（ 2） the sample obviously experiences the decay and steady creep periods under lower stress state,and soon appeared the accelerated creep period under higher stress,but the final deformation is less than the ultimate strain value under conventional triaxial compression test. Based on the experimental result,the creep parameters under different time and stresses are fitted out,then the mathematical expressions about the creep parameters vary with stress and time are fitted out. The variation of creep parameters could better reflect the deterioration process of the rock structure in decay and steady creep stages,which indicating that this creep equation can well simulate the creep characteristics of sandstone in decay and steady creep stages.
出处
《公路交通科技》
CAS
CSCD
北大核心
2016年第10期104-110,共7页
Journal of Highway and Transportation Research and Development
基金
国家自然科学基金项目(51274109)
关键词
隧道工程
蠕变特性
蠕变试验
砂岩
变参数蠕变
tunnel engineering
creep characteristic
creep test
sandstone
variable parameter creep
