交通荷载作用下安宁地区超固结重塑红黏土的动力特性试验研究

针对中石油云南石化铁路专用线高填路基填料红黏土,通过GDS振动三轴仪进行了一系列不同超固结比、围压、动应力幅值条件下重塑红黏土的循环加载动三轴试验,重点分析了不同因素对该地区超固结重塑红黏土的临界动应力、累积轴向动应变、动弹性模量以及动强度的影响规律。试验结果表明:超固结重塑红黏土在交通荷载作用下的临界动应力随超固结比、围压的增大而线性增大;超固结重塑红黏土的动强度与超固结比、围压成正比关系,循环振动次数对超固结红黏土的动内摩擦角影响较小,而对动黏聚力影响较大。上述试验结果可为该地区超固结重塑红黏土作为路基填料的工程提供一定实用价值。

Experimental study on dynamic characteristics of over-consolidated remolded red clay subjected to traffic load in Anning area

Aiming at the red clay filled with the high fill subgrade of Yunnan Petrochemical Corporation (affiliated to China National Petroleum Corporation, CNPC) Railway dedicated line, a series of cyclic loading dynamic triaxial experiments of remolded red clay under the condition of different over-consolidated ratio, confining pressure and dynamic stress amplitude were carried out by GDS vibration triaxial instrument. The influence of different factors on the critical dynamic stress, cumulative axial dynamic strain, dynamic elastic modulus and dynamic strength o the over consolidated remolded red clay in this area were analyzed emphatically. Experimental results indicated that the critical dynamic stress of the over-consolidated remolded red clay under traffic load increases linearly with the increase of over-consolidation ratio and confining pressure. The dynamic strength of the over-consolidated and remolded red clay is proportional to the over-consolidation ratio and confining pressure. The cyclic vibration times have little influence on the dynamic internal friction angle of the over-consolidated red clay, but have a great influence on the dynamic cohesive force. The test results can provide some practical value for the engineering of over-consolidated and remolded red clay as roadbed filler.