乌(西)奎(屯)城际铁路位于季节性冻土地区,局部区段路基为粉质黏土,在季节性冻融循环作用影响下,路基刚度大大降低,从而使路基产生不均匀变形,给列车运行带来不利影响.本文通过堆载加荷的方式,结合实际情况对乌奎城际铁路路基进行了K30试验检测,检验其路基刚度是否满足规范要求,并给出提高路基地基系数的方法.试验结果表明:乌奎城际铁路路基基床表层地基系数较低,不满足铁路路基相关规范要求;通过基床表层局部换填道砟并压密夯实的方式可以显著提高地基系数,起到补强路基的作用.
Wuxi-Kuitun inter-city railway is located in the seasonal frozen soil region and local section subgrade is filled with silty clay.Under the influence of seasonal freezing and thawing cycles,subgrade stiffness falls off remarkably,which causes uneven deformation of subgrade and casts a negative impact on the train operation.K30 test by surcharge loading means was carried out to detect subgrade stiffness of Wuxi-Kuitun inter-city railway,to examine whether the subgrade stiffness meeted the specification requirements,and the method of improving the foundation coefficient was put forward.The test results show that the foundation coefficient of Wuxi-Kuitun inter-city railway subgrade surface layer is too low to meet the requirements of railway subgrade.Inherent bedding surface replaced by dense ballast can significantly improve the foundation coefficient and play the role of reinforcing subgrade.