西北地区黄土路基沉降变形分析及治理

Analysis and Treatment of Loess Subgrade Settlement Deformation in Northwest China

针对西北地区某客运专线铁路黄土路基CFG桩+水泥挤密桩长短桩组合复合地基地段出现的沉降病害问题,根据现场实测、勘探取样室内试验及沉降监测,分析病害出现的原因,提出桩板结构路基作为补强措施;采用ABAQUS软件,分析不同桩长、桩径及桩间距情况下的沉降变形。结果表明:桩长和桩径的增加、桩间距的缩小均能减小沉降量,但相比桩径与桩间距的变化,桩长的增加对沉降的控制效果比较明显,当桩端嵌入到砂岩硬层中时,桩板结构路基的沉降很小。

In view of the settlement disease in the composite foundation section of CFG pile+cement compaction pile long and short piles of the loess subgrade of a Passenger Dedicated Track in Northwest China,according to the field measuring,exploration,sampling and monitoring,the causes of the disease are analyzed,and the pile-plate structure subgrade is proposed as a reinforcement measure.The ABAQUS software is used to analyze the settlement deformation under different pile lengths,pile diameters and pile spacing.The results show that the increase of pile lengths,pile diameters and the reduction of pile spacing can reduce the settlement,but compared with the change of pile diameters and pile spacing,the increase of pile lengths has an obvious control effect on the settlement.When the pile ends are embedded in the sandstone hard layer,the settlement of the pile-plate structure subgrade is very small.