无振动挤密地基处理技术在湿陷性黄土隧道中的应用

Application of Non-vibration Compaction Technology of Foundation Treatment in Collapsible Loess Tunnel

宝(鸡)兰(州)客专沿线湿陷性黄土分布广泛,其中44座隧道穿越黄土地层。黄土具有自重湿陷性,湿陷等级高(Ⅲ~Ⅳ级),孔隙比为0.9~1.3,极易在振动情况下产生振陷,导致隧道结构开裂、塌方,甚至导致边仰坡滑坡、滑塌等灾害,因此,采用挤密法进行地基处理为最优方案。本文针对湿陷性黄土隧道开展了无振动挤密桩地基处理工业化试验。试验结果表明:研制的无振动挤密设备成孔成桩性能良好,施工对隧道周边围岩基本无扰动;无振动挤密设备处理湿陷性黄土效果良好,满足铁路隧道相关规范要求。

The collapsible loess is widely distributed in Baoji-Lanzhou passenger dedicated railway. There are 44 tunnels through the loess stratum. The loess mostly has characteristics of gravity collapsibility, which presented high collapse grade （ Ⅲ - Ⅳ ）. The loess void ratio is 0.9 - 1.3. The settlement is easily induced in the condition of vibration, which can lead to cracking and collapse of tunnel structure, even lead to disasters of landslide and slump. So the compaction technology is the best method in foundation treatment. The industrial test of non-vibration compaction technology was applied in collapsible loess tunnel. The test results show that the pipe forming performance of non-vibration compaction equipment is good. There is no disturbance to surrounding rock around tunnel during construction. The treatment effect of collapsible loess is good by using the equipment, which can meet the specification requirements.