贵广高速铁路上寨隧道溶洞处理技术

以贵广高铁上寨隧道岩溶工程地质特征及隧道结构加强措施为例，对采用大管棚支护穿越坍方地段、堆积物充填大型溶洞段等软弱破碎围岩施工方法和旋喷桩对岩溶发育地段隧道底部进行加固处理的施工技术进行介绍。由于岩溶地质条件的复杂性，施工过程中进行超前地质预报并根据围岩地质条件进行动态设计，可有效降低施工安全风险及隧道结构安全风险；大管棚结合小导管注浆超前支护是穿越坍方地段、堆积物充填大型溶洞段的有效手段；且隧道底部较大较深溶洞采用旋喷柱加固效果良好。

Technique on Karst Cave Treatment for Shangzhai Tunnel on Guiyang-Guangzhou Express Railway

Taking the geological characteristics of the karst engineering for Shangzhai Tunnel on Guiyang-Guangzhou Express Railway and the tunnel structure reinforcement measures as the example，the paper introduced the construction methods，including support of large pipe shed used to go through the collapse section，deposits used to fill the large karst cave section and other soft and crushed surrounding rock，as well as the construction technique，such as jet grouting pile used to reinforce the bottom of tunnel within karst developing section.Because of the complex geological conditions，both the advanced geological forecast and the dynamic design depending on the geological conditions of the surrounding rock during the construction process may effectively reduce the risks in relation to safety of the construction and the tunnel structure；the advanced support of large pipe shed combined with small duct grouting is effective method to cross over collapse section and fill large karst cave section with deposits；and for large and deep karst cave in the bottom of tunnel，jet grouting pile is a good reinforcement measure.