高速铁路无砟轨道地基微膨胀泥岩膨胀性评价

为了对高速铁路无砟轨道地基微膨胀泥岩膨胀性进行评价,选取等效蒙脱石含量、阳离子交换量、自由膨胀率和液限为泥岩膨胀性判别指标,根据大量现场钻孔实测资料,在TB 10621-2014《铁路工程特殊岩土勘察规程》基础上对泥岩膨胀等级进行优化,采用改进层次分析法、基尼系数法和相对熵确定了判别指标组合权重,并基于改进灰关联分析法...

Expansibility Evaluation of Micro-swelling Mudstone in Ballastless Track Foundation of High-speed Railway

To evaluate the expansibility of the micro-swelling mudstone in ballastless track foundation of high-speed railway,the equivalent montmorillonite content,cation exchange capacity,free expansion rate and liquid limit were selected as discriminant indicators for the expansion of mudstone.The mudstone expansion grade was optimized based on a large number of on-site borehole survey data and the TB 10621—2014"Special Geotechnical Survey Regulations for Railway Engineering".The improved analytic hierarchy process,Gini coefficient method and relative entropy were used to determine the combined weight of the discriminant index.The expansion grade of mudstone was determined by improved grey relational analysis method.The results show that the application of the improved grey relational analysis method and the relative entropy combination weighting method to the evaluation of the expansiveness of the mudstone in the ballastless track foundation fully considers the range of the mudstone expansion level evaluation standard and overcomes the shortcomings of the existing comprehensive evaluation methods in considering the weights of discriminant indicators.When the mudstone expansion level is above GradeⅢ,it will cause the arch of the ballastless track subgrade of the high-speed railway and corresponding engineering measures should be taken.The research results provide a theoretical basis for the engineering control measures for long-term continuous camber deformation of the mudstone of high-speed railway subgrade.