风积沙压实特性及填筑重载铁路路基压实工艺

Compaction Characteristics of Aeolian Sand and Compaction Technology for Filling Subgrade of Heavy Haul Railway

以毛乌素沙漠风积沙为研究对象,研究该地区风积沙的颗粒级配特性、压实特性和作为重载铁路路基填料填筑基床以下部位的现场压实工艺。结果表明:风积沙的颗粒组成较细且十分均匀,其粒径主要分布在0.25~0.075 mm,属于颗粒级配不良的细砂;风积沙的击实特性具有双峰值现象,往往呈倒S形,可以在干燥或最佳含水率时压实,得到相对较大的干密度;风积沙填筑路基时采用湿压法效果较好;由于风积沙的保水性差,在碾压过程中应注意保持风积沙的含水率,若含水率较低时,应及时洒水;风积沙的压实质量在最佳含水率附近碾压时随着碾压遍数增加逐渐提高。

Based on the aeolian sand in Mu Us desert, the particle size distribution characteristics and compaction characteristics of aeolian sand in this area were studied. The field compaction technology of aeolian sand as heavy haul railway bedding filling of subgrade was established. The results show that the particle size of the aeolian sand is fine and very uniform with size range of 0.25 - 0. 075 mm, which belongs to the fine sand with poor particle size distribution. The compaction characteristics of the aeolian sand have ＂ double-peak＂ phenomenon with inverted S-shaped,can be compacted while aeolian sand dry or in optimum water content to obtain a relatively large dry density. The effect of wet compaction method when aeolian sand filling subgrade is better. Due to the water retention of aeolian sand is poor, in the rolling process should pay attention to maintain the water content of aeolian sand. If the water content is low, timely watering is needed. Aeolian sand compaction quality increases gradually with more rolling times near the optimum water content.